@article{gyawali_kandel_lee_shrestha_pandey_akter_hahn_2024, title={Silver decoration of Cr2O3 nanoparticles: Facile preparation of Cr2O3 nanoparticles and Ag-Cr2O3 nanocomposites and characterization of their antibacterial activity and ability to photocatalytically degrade organic wastes under visible light}, volume={447}, ISSN={["1873-2666"]}, DOI={10.1016/j.jphotochem.2023.115251}, abstractNote={An eco-friendly, single-step process was adopted for the preparation of Cr2O3 nanoparticles (CR-NPs), and different concentrations of Ag were doped into the CR-NPs through liquid impregnation to synthesize a series of Ag-CRNPs composites. In order to prevent agglomeration, chemical transformation, and weak adhesion of Ag to CR-NPs, a mechanical process of circular-motion grinding and high-temperature treatment in a sealed condition were used. Well-defined heterojunctions were successfully formed between Ag and CR-NPs. In comparison to the CR-NPs, the Ag-doped CR-NP composites exhibited excellent performance in photocatalytic and antibacterial applications. Under visible light (VL), the best-performing composite (2 %-Ag decorated CR-NPs) showed 96 %, 79 %, and 57 % decomposition of methylene blue, Congo red, and tetracycline, respectively, in 100 min, which was attributed to a synergetic effect in the composites. The rate constant of the photocatalytic reaction is 14 times higher than that of the reaction without a photocatalyst. The enhanced efficiency was attributed to a reduced bandgap, prolonged retention of photogenerated electron–hole pairs, an increased amount of active spots, and increased absorption of VL. Similarly, the best-performing composite exhibited excellent antibacterial activity against Escherichia coli and Staphylococcus aureus with zones of inhibition of 15.4 and 15.1 mm, respectively. The 2 %-Ag decorated CR-NPs were the most efficient and exhibited robust recyclability until the fifth cycle (≥90 %). The photocatalytic activity was primarily driven by reactive oxygen species, holes and hydroxyl radicals.}, journal={JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY}, author={Gyawali, Narayan and Kandel, Rupesh and Lee, Insup and Shrestha, Santu and Pandey, Anil and Akter, Jeasmin and Hahn, Jae Ryang}, year={2024}, month={Jan} }
 @article{islam_riaz_hossain_lee_akter_shrestha_gyawali_pandey_chaizul_fualo_et al._2023, title={Controlled release of Ag<SUP>+</SUP> ions to human cancer cells selectively neutralized with silver nanoparticles of different sizes produced by a green synthesis method}, volume={1294}, ISSN={["1872-8014"]}, DOI={10.1016/j.molstruc.2023.136384}, abstractNote={We present a facile green method to synthesize silver nanoparticles (AgNPs) with different sizes and uniform size distributions using an extract of Rhododendron mucronulatum flowers. Here, AgNPs were utilized to modify the release of Ag+ ions and selectively annihilate human cancer cells. AgNPs were prepared at ambient temperature (RT-AgNPs) and in higher-temperature water baths at 60 °C (W60-AgNPs) and 70 °C (W70-AgNPs) to modify the diameter and uniformity of the AgNPs. The W60-AgNPs were further treated with acid to modify their size and surface state (named AW60-AgNPs). The water-bath technique enabled an alteration of the relative rates of initial nucleation and growth of nanoparticles in a homogeneous environment, promoting the creation of small AgNPs with a uniform diameter distribution. The acid treatment eroded the surface particles to reduce their diameter and simultaneously introduced functional groups. The Ag+-ion release efficiency of the prepared nanoparticles and the toxicity of Ag+ ions on cancer cells were examined. Among the prepared samples, the AW60-AgNPs released the greatest amount of Ag+ ions and produced the largest amount of reactive oxygen species (O2̇−, ˙OH, and H2O2). All of the AgNP samples were applied to tumor cells (K562 and HT1080) and healthy cells (LO2) in vitro. In the presence of K562 cells, AW60-AgNPs showed the most efficient dose- and time-dependent early and late apoptosis as well as reduced viability. A crystal violet assay showed that the synthesized particles preferentially attack HT1080 cancer cells rather than LO2 normal cells. We found that Ag+ ions release efficiency and selectivity varied with particle size, and that DNA damage in tumor cells was due to the formation of Ag+-coordinated complexes within DNA base pairs.}, journal={JOURNAL OF MOLECULAR STRUCTURE}, author={Islam, Md. Akherul and Riaz, Thoufiqul Alam and Hossain, Md. Amjad and Lee, Insup and Akter, Jeasmin and Shrestha, Santu and Gyawali, Narayan and Pandey, Anil and Chaizul, Syawalina and Fualo, Vince and et al.}, year={2023}, month={Dec} }
 @article{akter_abu hanif_lee_shrestha_pandey_gyawali_chaizul_fualo_kwac_hahn_2023, title={Nanostructured carbon and copper oxide: Synchronous and facile synthesis from a single source and multidimensional applications}, volume={471}, ISSN={["1873-3212"]}, DOI={10.1016/j.cej.2023.144603}, abstractNote={Carbon nanoparticles (C-NPs) and CuO nanorods (CuO-NRs) are important materials with applications in various fields. In this work, a cost-effective and rapid approach for synthesizing C-NPs, CuO-NRs, and CuO/C nanocomposites using copper(II) acetate hydrate (CAH) as a single precursor was developed. CAH serves as a source of both C and CuO. The as-synthesized C-NPs were hydrophilic and also dispersible in non-aqueous media. They exhibited excitation-dependent and -independent photoluminescence properties. The C-NPs and CuO-NRs were prepared by thermal decomposition and acid treatment, and the CuO/C nanocomposites were prepared using straightforward co-crystallization techniques. The photocatalytic effectiveness of the prepared composites for the decomposition of methylene blue (MB), non-photosensitizing Congo red (CR), and rhodamine 6G (R6G) dyes was evaluated under visible light. Among the composites, CUOC-2 (with a C/CuO weight ratio of 1:0.75) displayed the highest activity. Specifically, in the presence of CUOC-2, 98.54%, 94.31%, and 76.01% of MB, CR, and R6G were degraded within reaction times of 70, 40, and 70 min, respectively. The combination of C and CuO makes the composites effective photocatalysts. In addition, the nanocomposites demonstrated excellent electrocatalytic properties, including high oxygen/hydrogen evolution reaction (OER/HER) activities. The as-synthesized C-NPs, CUOC-2 nanocomposites, and CuO-NRs required 323, 270, and 249 mV for HER and 268, 378, and 462 for OER to reach a current response of 10 mA/cm2, indicating that they are promising catalysts for green hydrogen production via water splitting.}, journal={CHEMICAL ENGINEERING JOURNAL}, author={Akter, Jeasmin and Abu Hanif, Md. and Lee, Insup and Shrestha, Santu and Pandey, Anil and Gyawali, Narayan and Chaizul, Syawalina and Fualo, Vince and Kwac, Lee Ku and Hahn, Jae Ryang}, year={2023}, month={Sep} }
 @article{shrestha_sapkota_lee_islam_pandey_gyawali_akter_mohan_shin_jeong_et al._2022, title={Carbon-Based Ternary Nanocomposite: Bullet Type ZnO-SWCNT-CuO for Substantial Solar-Driven Photocatalytic Decomposition of Aqueous Organic Contaminants}, volume={27}, ISSN={["1420-3049"]}, DOI={10.3390/molecules27248812}, abstractNote={A facile two-step synthesis of ternary hetero-composites of ZnO, CuO, and single-walled carbon nanotubes (SWCNTs) was developed through a recrystallization process followed by annealing. A series of nanocomposites were prepared by varying the weight ratio of copper(II) acetate hydrate and zinc(II) acetate dihydrate and keeping the weight ratio of SWCNTs constant. The results revealed the formation of heterojunctions (ZnO–SWCNT–CuO, ZSC) of three crystal structures adjacent to each other, forming a ternary wurtzite-structured nanoparticles along with defects. Enhanced charge separation (electron-hole pairs), reduced band gap, defect-enhanced specific surface area, and promoted oxidation potential were key factors for the enhanced photocatalytic activity of the ternary nanocomposites. OH• radicals were the main active species during dye degradation, and O2−• and h+ were also involved to a lesser extent. A type II heterojunction mechanism approach is proposed based on the charge carrier migration pattern. Among the synthesized nanocomposites, the sample prepared using copper(II) acetate hydrate and zinc(II) acetate dihydrate in a 1: 9 ratio (designated a ZSC3) showed the highest photocatalytic activity. ZSC3 achieved 99.2% photodecomposition of methylene blue in 20 min, 94.1% photodecomposition of Congo red in 60 min, and 99.6% photodecomposition of Rhodamine B in 40 min under simulated sunlight. Additionally, ZSC3 showed excellent reusability and stability, maintaining 96.7% of its activity even after five successive uses. Based on overall results, the ZSC sample was proposed as an excellent candidate for water purification applications.}, number={24}, journal={MOLECULES}, author={Shrestha, Santu and Sapkota, Kamal Prasad and Lee, Insup and Islam, Md Akherul and Pandey, Anil and Gyawali, Narayan and Akter, Jeasmin and Mohan, Harshavardhan and Shin, Taeho and Jeong, Sukmin and et al.}, year={2022}, month={Dec} }
 @article{hanif_akter_islam_lee_sapkota_shrestha_pandey_gyawali_hahn_2022, title={Enhancement of visible-light photocatalytic activity of ZnO/ZnS/g-C3N4 by decreasing the bandgap and reducing the crystallite size via facile one-step fabrication}, volume={431}, ISSN={["1873-2666"]}, DOI={10.1016/j.jphotochem.2022.114066}, abstractNote={Ternary ZnO/ZnS/g-C3N4 (ZZGC) nanocomposites were synthesized via a modified high-pressure solvent-free thermal method and subsequently used as highly efficient visible-light-driven photocatalysts to degrade organic pollutants. ZZGC composites were prepared at different temperatures and characterized by several microscopic and spectroscopic techniques. The best composite (named ZZGC-1, prepared at 400℃) exhibited 98.39% photocatalytic efficiency of methylene blue (MB) dye within 70 min under visible-light illumination. In addition, ZZGC-1 showed 1185% and 222% greater activity compared with similar reactions involving no catalyst and involving the corresponding binary composite (ZnO/ZnS prepared at 400℃), respectively. Under the same experimental conditions, ZZGC-1 demonstrated 89.04% efficiency for the deterioration of Congo red dye. The enhanced photocatalytic activity of ZZGC-1 may be due to its greater specific surface area compared with that of other composite photocatalysts. No substantial loss of activity or structural arrangement of ZZGC-1 was detected after five successive cycles. Overall, ZZGC nanocomposites can be used for practical and quick visible-light-driven photocatalytic wastewater treatment.}, journal={JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY}, author={Hanif, Md. Abu and Akter, Jeasmin and Islam, Md. Akherul and Lee, Insup and Sapkota, Kamal Prasad and Shrestha, Santu and Pandey, Anil and Gyawali, Narayan and Hahn, Jae Ryang}, year={2022}, month={Oct} }
 @article{islam_akter_lee_shrestha_pandey_gyawali_hossain_abu hanif_jang_hahn_2022, title={Facile Preparation of a Bispherical Silver-Carbon Photocatalyst and Its Enhanced Degradation Efficiency of Methylene Blue, Rhodamine B, and Methyl Orange under UV Light}, volume={12}, ISSN={["2079-4991"]}, DOI={10.3390/nano12223959}, abstractNote={The combination of organic and inorganic materials is attracting attention as a photocatalyst that promotes the decomposition of organic dyes. A facile thermal procedure has been proposed to produce spherical silver nanoparticles (AgNPs), carbon nanospheres (CNSs), and a bispherical AgNP–CNS nanocomposite. The AgNPs and CNSs were each synthesized from silver acetate and glucose via single- and two-step annealing processes under sealed conditions, respectively. The AgNP–CNS nanocomposite was synthesized by the thermolysis of a mixture of silver acetate and a mesophase, where the mesophase was formed by annealing glucose in a sealed vessel at 190 °C. The physicochemical features of the as-prepared nanoparticles and composite were evaluated using several analytical techniques, revealing (i) increased light absorption, (ii) a reduced bandgap, (iii) the presence of chemical interfacial heterojunctions, (iv) an increased specific surface area, and (v) favorable band-edge positions of the AgNP–CNS nanocomposite compared with those of the individual AgNP and CNS components. These characteristics led to the excellent photocatalytic efficacy of the AgNP–CNS nanocomposite for the decomposition of three pollutant dyes under ultraviolet (UV) radiation. In the AgNP–CNS nanocomposite, the light absorption and UV utilization capacity increased at more active sites. In addition, effective electron–hole separation at the heterojunction between the AgNPs and CNSs was possible under favorable band-edge conditions, resulting in the creation of reactive oxygen species. The decomposition rates of methylene blue were 95.2, 80.2, and 73.2% after 60 min in the presence of the AgNP–CNS nanocomposite, AgNPs, and CNSs, respectively. We also evaluated the photocatalytic degradation efficiency at various pH values and loadings (catalysts and dyes) with the AgNP–CNS nanocomposite. The AgNP–CNS nanocomposite was structurally rigid, resulting in 93.2% degradation of MB after five cycles of photocatalytic degradation.}, number={22}, journal={NANOMATERIALS}, author={Islam, Md Akherul and Akter, Jeasmin and Lee, Insup and Shrestha, Santu and Pandey, Anil and Gyawali, Narayan and Hossain, Md Monir and Abu Hanif, Md and Jang, Se Gyu and Hahn, Jae Ryang}, year={2022}, month={Nov} }
 @article{sapkota_lee_shrestha_islam_hanif_akter_hahn_2021, title={Coherent CuO-ZnO nanobullets maneuvered for photocatalytic hydrogen generation and degradation of a persistent water pollutant under visible-light illumination}, volume={9}, ISSN={["2213-3437"]}, DOI={10.1016/j.jece.2021.106497}, abstractNote={CuO–ZnO nanocomposite photocatalysts synthesized via a facile co-crystallization process followed by high pressure annealing demonstrated excellent photocatalysis of H2 gas generation via water splitting as well as methylene blue (MB) dye degradation. Morphological analyses revealed that CuO nanoparticles readily combined with ZnO crystals to give rise to unique hierarchical bullet-shaped composite particles referred to as nanobullets. Elemental analyses confirmed the uniform distribution of CuO nanoparticles in the ZnO nanobullets. X-ray photoelectron spectroscopic analysis showed peak shifts associated with changes in the electronic states of the Cu and Zn species, confirming the formation of a heterojunction. Successful heterojunction formation was further supported by several imaging and spectroscopic techniques. The composite samples demonstrated enhanced photocatalytic activity compared with both uncombined ZnO and uncombined CuO. Among the as-synthesized nanocomposites, the sample annealed for 30 min (abbreviated as CZ-30) displayed the highest activity, generating 4.094 millimoles of H2 within 3 h and 98.6% photodegradation of MB within 80 min under exposure to visible light. Such an enhancement in photocatalytic performance was ascribed to the synergistic migration of charge carriers across the heterojunction of the composites. A mechanism of synergistic photocatalysis was proposed on the basis of the results.}, number={6}, journal={JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING}, author={Sapkota, Kamal Prasad and Lee, Insup and Shrestha, Santu and Islam, Akherul and Hanif, Abu and Akter, Jeasmin and Hahn, Jae Ryang}, year={2021}, month={Dec} }
 @article{abu hanif_akter_lee_islam_sapkota_abbas_hahn_2021, title={Formation of chemical heterojunctions between ZnO nanoparticles and single-walled carbon nanotubes for synergistic enhancement of photocatalytic activity}, volume={413}, ISSN={["1873-2666"]}, DOI={10.1016/j.jphotochem.2021.113260}, abstractNote={A series of nanocomposites composed of spherical ZnO nanoparticles (ZNPs, average diameter of 119 nm) and single-walled carbon nanotubes (average diameter of 1.1 nm) (ZNP–SWCNT) were synthesized. The synergistic effect of the SWCNTs on the photocatalytic efficiency of the ZNPs for the degradation of methylene blue dye under UV-light was demonstrated. The as-synthesized nanocomposites, pure ZNPs, and the pristine SWCNTs exhibited pseudo-first-order kinetic behavior in the decomposition of the dye. The decomposition rate constant in the presence of the nanocomposite varied with the amount of SWCNTs. The maximum rate constant was 680 % and 2570 % greater than those of the pure ZNPs and the pristine SWCNTs, respectively. It was found that the optical bandgap of the pure ZNPs was considerably narrowed, and their maximum UV absorbance was red-shifted upon composite formation between the SWCNTs and ZNPs. Those results suggested that the SWCNTs played a crucial role in the improvement of the catalytic activity of the ZNPs. Such a synergistic effect was due to the creation of a chemical heterojunction between the SWCNTs and the ZNPs. Moreover, the prepared nanocomposite demonstrated remarkable reusability: the photocatalytic efficiency was reduced by only 3.62 % after the fifth cycle.}, journal={JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY}, author={Abu Hanif, Md and Akter, Jeasmin and Lee, Insup and Islam, Md Akherul and Sapkota, Kamal Prasad and Abbas, Hafiz Ghulam and Hahn, Jae Ryang}, year={2021}, month={May} }
 @article{sapkota_islam_abu hanif_akter_lee_hahn_2021, title={Hierarchical Nanocauliflower Chemical Assembly Composed of Copper Oxide and Single-Walled Carbon Nanotubes for Enhanced Photocatalytic Dye Degradation}, volume={11}, ISSN={["2079-4991"]}, DOI={10.3390/nano11030696}, abstractNote={We present the fabrication and proficient photocatalytic performance of a series of heterojunction nanocomposites with cauliflower-like architecture synthesized from copper(II) oxide (CuO) nanocrystals and carbon nanotubes with single walls (SWCNTs). These unique photocatalysts were constructed via simplistic recrystallization succeeded by calcination and were labeled as CuOSC-1, CuOSC-2, and CuOSC-3 (representing the components; CuO and SC for SWCNTs, and the calcination time in hours). The photocatalytic potency of the fabricated nanocomposites was investigated on the basis of their capability to decompose methylene blue (MB) dye under visible-light irradiation. Every as-synthesized nanocomposite was effective photocatalyst for the photodecomposition of an MB solution. Moreover, CuOSC-3 exhibited the best photocatalytic activity, with 96% degradation of the visible-light irradiated MB solution in 2 h. Pure CuO nanocrystals generated through the same route and pure SWCNTs were used as controls, where the photocatalytic actions of the nanocomposite samples were found to be remarkably better than that of either the pure CuO or the pure SWCNTs. The recycling proficiency of the photocatalysts was also explored; the results disclosed that the samples could be applied for five cycles without exhibiting a notable change in photocatalytic performance or morphology.}, number={3}, journal={NANOMATERIALS}, author={Sapkota, Kamal Prasad and Islam, Md Akherul and Abu Hanif, Md and Akter, Jeasmin and Lee, Insup and Hahn, Jae Ryang}, year={2021}, month={Mar} }
 @article{akter_sapkota_abu hanif_islam_abbas_hahn_2021, title={Kinetically controlled selective synthesis of Cu2O and CuO nanoparticles toward enhanced degradation of methylene blue using ultraviolet and sun light}, volume={123}, ISSN={["1873-4081"]}, DOI={10.1016/j.mssp.2020.105570}, abstractNote={Two different stable forms of copper oxide (Cu2O and CuO) nanoparticles (NPs) were selectively synthesized through a smart approach using the same precursor but different reagent amounts. The fabrication strategy is cost-effective and relatively easy. The bandgap energies of the as-synthesized Cu2O- and CuO-NPs, as determined from Tauc plots, are 2.08 and 1.82 eV, respectively. The photocatalytic performance of these NPs was assessed through their use in the photodegradation of an organic-dye water contaminant under UV and solar-light illumination. Methylene blue (MB) was chosen as a representative dye because of its ubiquitous presence in industrial wastewater and its hazardous effects on human health. The results of experiments involving the photodegradation of MB by the synthesized Cu2O- and CuO-NPs revealed 97% and 81% photodecomposition efficiencies, respectively, during 60 min of UV-light illumination. When sunlight was used as a light source, and the duration was extended to 120 min, the photodecomposition efficiencies were 70% and 63% for the Cu2O- and CuO-NP photocatalysts, respectively. The efficient degradation of MB solution by the as-prepared NPs implies that they are potentially potent photocatalysts for the treatment of wastewater originating from industrial and domestic sources.}, journal={MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING}, author={Akter, Jeasmin and Sapkota, Kamal Prasad and Abu Hanif, Md. and Islam, Md. Akherul and Abbas, Hafiz Ghulam and Hahn, Jae Ryang}, year={2021}, month={Mar} }
 @article{abbas_debela_hahn_kang_2021, title={Multiferroicity of Non-Janus MXY (X = Se/S, Y = Te/Se) Monolayers with Giant In-Plane Ferroelectricity}, volume={125}, ISSN={["1932-7455"]}, DOI={10.1021/acs.jpcc.1c00949}, abstractNote={Using first-principles calculation, we show that two non-Janus configurations, i.e., Se2Te1 and Se2Te2, of MSeTe (M = Mo or W) monolayers (MLs) are not only considerably more stable than Janus conf...}, number={13}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, author={Abbas, Hafiz Ghulam and Debela, Tekalign Terfa and Hahn, Jae Ryang and Kang, Hong Seok}, year={2021}, month={Apr}, pages={7458–7465} }
 @article{akter_hanif_islam_sapkota_hahn_2021, title={Selective growth of Ti3+/TiO2/CNT and Ti3+/TiO2/C nanocomposite for enhanced visible-light utilization to degrade organic pollutants by lowering TiO2-bandgap}, volume={11}, ISSN={["2045-2322"]}, DOI={10.1038/s41598-021-89026-5}, abstractNote={Abstract A convenient route was developed for the selective preparation of two stable nanocomposites, Ti 3+ /TiO 2 /CNT (labeled as TTOC-1 and TTOC-3) and Ti 3+ /TiO 2 /carbon layer (labeled as TTOC-2), from the same precursor by varying the amount of single-walled carbon nanotubes used in the synthesis. TiO 2 is an effective photocatalyst; however, its wide bandgap limits its usefulness to the UV region. As a solution to this problem, our prepared nanocomposites exhibit a small bandgap and wide visible-light (VL) absorption because of the introduction of carbonaceous species and Ti 3+ vacancies. The photocatalytic efficiency of the nanocomposites was examined via the degradation of methylene blue dye under VL. Excellent photocatalytic activity of 83%, 98%, and 93% was observed for TTOC-1, TTOC-2, and TTOC-3 nanocomposites within 25 min. In addition, the photocatalytic degradation efficiency of TTOC-2 toward methyl orange, phenol, rhodamine B, and congo red was 28%, 69%, 71%, and 91%, respectively, under similar experimental conditions after 25 min. Higher reusability and structural integrity of the as-synthesized photocatalyst were confirmed within five consecutive runs by photocatalytic test and X-ray diffraction analysis, respectively. The resulting nanocomposites provide new insights into the development of VL-active and stable photocatalysts with high efficiencies.}, number={1}, journal={SCIENTIFIC REPORTS}, author={Akter, Jeasmin and Hanif, Md Abu and Islam, Md Akherul and Sapkota, Kamal Prasad and Hahn, Jae Ryang}, year={2021}, month={May} }
 @article{islam_sapkota_riaz_hossain_abu hanif_akter_hossain_jang_chae_hahn_2021, title={Subnanometer Thick Carbon-Layer-Encapsulated Silver Nanoparticles Selectively Neutralizing Human Cancer Cells and Pathogens through Controlled Release of Ag+ Ions}, volume={4}, ISSN={["2574-0970"]}, DOI={10.1021/acsanm.1c01276}, abstractNote={We present the excellent and selective activity against human cancer cells and pathogens by double-layer carbon-encapsulated silver nanoparticles ([email protected]) and monolayer carbon-encapsulated silver nanoparticles ([email protected]). [email protected] were synthesized via a modified solvothermal approach, whereas [email protected] were prepared by exfoliation of the outer carbon layer of [email protected] The physicochemical structures and properties of the [email protected] and [email protected] are thoroughly examined; the carbon layer is found to ensure the needful release of Ag+ ions from the core Ag nanoparticles, and improve the biocompatibility and selectivity of NPs to kill the cancer cells. Hence, the [email protected] and [email protected] are substantiated to be beneficial for controlling the overtoxicity caused by unstable bare AgNPs and achieving the targeted actions. The Ag+ ions exhibit their toxic effects against cancer cells or pathogens chiefly through the reactive oxygen species (ROS) generation. The Ag+-ion release and ROS generation of the [email protected] are found greater than those of the [email protected] because of the synergistic effect of the reduced thickness of carbon layer and increased specific surface area. The [email protected] and [email protected] were applied against cancer cells (K562 and Hep3B), normal cells (LO2), and pathogens in vitro. The [email protected] exhibit greater dose- and time-dependent late apoptosis of cancer cells than the [email protected], and reduce the viability of cancer cells more effectively than the [email protected] The crystal violet assay explicitly displays that the as-prepared samples exhibit preferential attack on cancer cells. In the analysis of apoptosis associated proteins, caspase-3 and PARP as markers, the protein expression was visible only for the cancer cells asserting that the prepared [email protected] and [email protected] act selectively, invading only the cancer cells. Moreover, the [email protected] exhibit a larger linear inhibition zone than the [email protected] against both Gram negative and Gram positive pathogenic bacterial stains in bactericidal activity probes.}, number={7}, journal={ACS APPLIED NANO MATERIALS}, author={Islam, Md Akherul and Sapkota, Kamal Prasad and Riaz, Thoufiqul Alam and Hossain, Md Amjad and Abu Hanif, Md and Akter, Jeasmin and Hossain, Md Monir and Jang, Se Gyu and Chae, Han-Jung and Hahn, Jae Ryang}, year={2021}, month={Jul}, pages={7295–7308} }
 @article{akter_abu hanif_islam_sapkota_lee_hahn_2021, title={Visible-light-active novel alpha-Fe2O3/Ta3N5 photocatalyst designed by band-edge tuning and interfacial charge transfer for effective treatment of hazardous pollutants}, volume={9}, ISSN={["2213-3437"]}, DOI={10.1016/j.jece.2021.106831}, abstractNote={Novel α-Fe2O3/Ta3N5 nanocomposites were designed based on the Z-scheme system and a suitable band-edge potential for photocatalytic action. The combination of α-Fe2O3 and Ta3N5 showed substantially higher photocatalytic activity compared with α-Fe2O3 or Ta3N5 alone. The improved performance was attributed to (i) efficient electron–hole separation at the interface between α-Fe2O3 and Ta3N5, which resulted in high light absorption; and (ii) a favorable band-edge position to generate reactive oxygen species. The nanocomposites were prepared by precipitation techniques and annealing at different temperatures in a sealed chamber. The photocatalytic activity of the samples in methylene blue degradation under visible light (VL) was monitored for 60 min. The best result of 98.26% was obtained for the FTN-1 nanocomposite (annealed at 450 ℃), which is attributed to its high surface area, small particle size, and small crystallite size. Under similar conditions, FTN-1 exhibited 83.73%, 94.19%, and 48.86% efficiency in degrading rhodamine 6 G, non-photosensitizing Congo red, and the colorless contaminant phenol. The rate of MB degradation by FTN-1 was 539.4% and 651.2% greater than the rates of MB degradation by single catalysts α-Fe2O3 and Ta3N5, respectively. These values increased to 1939.4% and 2341.5% at pH 12 and a degradation time of 15 min. No substantial loss of activity or structural composition was observed after five consecutive runs. Overall, the nanocomposites exhibited a wide range of VL absorption and high photocatalytic efficiency. These results shed new light on the VL-active, Z-scheme photocatalyst field and indicate that the proposed photocatalysts are suitable for practical wastewater treatment.}, number={6}, journal={JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING}, author={Akter, Jeasmin and Abu Hanif, Md and Islam, Md Akherul and Sapkota, Kamal Prasad and Lee, Insup and Hahn, Jae Ryang}, year={2021}, month={Dec} }
 @article{abu hanif_akter_islam_sapkota_hahn_2021, title={Visible-light-driven enhanced photocatalytic performance using cadmium-doping of tungsten (VI) oxide and nanocomposite formation with graphitic carbon nitride disks}, volume={565}, ISSN={["1873-5584"]}, DOI={10.1016/j.apsusc.2021.150541}, abstractNote={We designed novel Cd-doped WO3 (CWC) and Cd-doped WO3@g-C3N4 (CWCC) heterostructure nanocomposites using a facile process and used them to remove pollutants from wastewater under visible light (VL). The g-C3N4 was designed in the form of a disk (CNDs) to facilitate the formation of CWCC composite. The photocatalytic efficiency of the CWCC was studied via the decomposition of methylene blue (MB), rhodamine 6G (Rh 6G), methyl red (MR), and methyl orange (MO). Outstanding photocatalytic performance of 95.98% was achieved within 80 min for MB. The efficiency of CWCC was 670%, 350%, 220%, 130%, and 121% greater than that of the blank, CNDs, pristine WO3, CWC, and WO3/g-C3N4 nanodisks, respectively. Under the same experimental conditions, the photocatalytic performance of CWCC was 82.22%, 77.51%, and 42.90% towards Rh 6G, MR, and MO, respectively. The increased catalytic efficiency of CWCC was attributed to a lowering of the bandgap and a favorable potential-energy location of the valence band and conduction band for photocatalysis by Cd doping and/or the formation of a heterojunction between the CWC and CNDs compositing with CNDs. The presence of a heterojunction enhanced the charge transfer and diminished the recombination of charge carriers. Two probable mechanisms are discussed.}, journal={APPLIED SURFACE SCIENCE}, author={Abu Hanif, Md and Akter, Jeasmin and Islam, Md Akherul and Sapkota, Kamal Prasad and Hahn, Jae Ryang}, year={2021}, month={Nov} }
 @article{sapkota_lee_hanif_islam_akter_hahn_2020, title={Enhanced Visible-Light Photocatalysis of Nanocomposites of Copper Oxide and Single-Walled Carbon Nanotubes for the Degradation of Methylene Blue}, volume={10}, ISSN={["2073-4344"]}, DOI={10.3390/catal10030297}, abstractNote={We report enhanced catalytic action of a series of copper(II)-oxide-single-walled carbon nanotube (CuO-SWCNT) composite photocatalysts (abbreviated as CuO-SWCNT-0.5, CuO-SWCNT-2, and CuO-SWCNT-5, where 0.5, 2, and 5 represent the calcination time in hours) synthesized via recrystallization followed by calcination. The photocatalytic performance of the fabricated nanocomposites was examined by evaluating the degradation of methylene blue (MB) under irradiation with visible light. All of the as-fabricated nanocomposites were effective photocatalysts for the photodegradation of a MB solution; however, the CuO-SWCNT-5 displayed the best photocatalytic ability among the investigated catalysts, achieving 97.33% degradation of MB in 2 h under visible-light irradiation. The photocatalytic action of the nanocomposites was remarkably higher than that of pristine CuO nanocrystals fabricated using the same route. The recyclability of the photocatalyst was also investigated; the CuO-SWCNT-5 catalyst could be reused for three cycles without substantial degradation of its catalytic performance or morphology.}, number={3}, journal={CATALYSTS}, author={Sapkota, Kamal Prasad and Lee, Insup and Hanif, Md. Abu and Islam, Md. Akherul and Akter, Jeasmin and Hahn, Jae Ryang}, year={2020}, month={Mar} }
 @article{sapkota_hassan_shrestha_abu hanif_islam_akter_abbas_hahn_2020, title={Heterojunction formation between copper(II) oxide nanoparticles and single-walled carbon nanotubes to enhance antibacterial performance}, volume={590}, ISSN={["1873-3476"]}, DOI={10.1016/j.ijpharm.2020.119937}, abstractNote={We delineate the excellent bactericidal efficacy of stable heterojunction nanocomposites composed of single-walled carbon nanotubes (SWCNTs) and copper(II) oxide (CuO) synthesized via facile recrystallization and calcination. The bactericidal effectiveness of the fabricated nanocomposites was examined using the standard broth-dilution method and the growth-inhibition-zone analysis method, in which bacteria cultured in an incubator in tryptic soy broth medium were subjected to the prepared samples. The bactericidal activity of all of the as-synthesized samples is evident in both methods, displaying a substantial decrease in bacterial colonies and resulting in clear inhibition zones, respectively. Among the CuO–SWCNT nanocomposites, the sample subjected to calcination at 500 °C for 5 h was found to exhibit the best performance against Staphylococcus aureus and Escherichia coli, forming inhibition zones 182% and 162% larger than those formed by pure CuO, respectively.}, journal={INTERNATIONAL JOURNAL OF PHARMACEUTICS}, author={Sapkota, Kamal Prasad and Hassan, Md. Mehedi and Shrestha, Sita and Abu Hanif, Md. and Islam, Md. Akherul and Akter, Jeasmin and Abbas, Hafiz Ghulam and Hahn, Jae Ryang}, year={2020}, month={Nov} }
 @article{abbas_hahn_kang_2020, title={Non-Janus WSSe/MoSSe Heterobilayer and Its Photocatalytic Band Offset}, volume={124}, ISSN={["1932-7455"]}, DOI={10.1021/acs.jpcc.9b08255}, abstractNote={We propose two non-Janus configurations, i.e., S2Se1 and S2Se2, of MoSSe and WSSe monolayers, which are appreciably more stable than their parent Janus configuration by proper exchanges of equivalent S and Se atoms. Specifically, S2Se1 is not only the most stable in the energetic sense but also dynamically stable. Our HSE06+SOC band structure calculation shows that the monolayers exhibit band gaps in the visible region comparable to those of the Janus configuration. S2Se1 WSSe exhibits a direct gap for the spin-up component, while it displays an indirect gap for the spin-down component due to the strong spin–orbit interaction. Our calculation of the activation barrier indicates that the Janus configuration can be converted to S2Se1 by a 15% uniaxial strain. Due to the absence of vertical polarization, we finally show that a S2Se1 WSSe/MoSSe heterobilayer can be much more advantageous than a Janus heterobilayer for the photocatalytic reduction of CO2 to CO or HCOOH in almost the entire pH range.}, number={6}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, author={Abbas, Hafiz Ghulam and Hahn, Jae Ryang and Kang, Hong Seok}, year={2020}, month={Feb}, pages={3812–3819} }
 @article{zahid_hanif_lee_islam_hahn_2019, title={Effect of amino, hydroxyl, and carboxyl terminal groups of alkyl chains of self-assembled monolayers on the adsorption pattern of gold nanoparticles}, volume={51}, ISSN={["1096-9918"]}, DOI={10.1002/sia.6697}, abstractNote={The adsorption pattern of gold nanoparticles (AuNPs) on functionalized self‐assembled monolayers (SAMs) produced on a Au(111) surface was characterized. The Au(111) was modified with 11‐amino‐1‐undecanethiol hydrochloride (AUT), 11‐mercapto‐1‐undecanol (MUT), or 11‐mercaptoundecanoic acid (MUA) at an elevated temperature and pressure. The AuNPs aggregated on the AUT‐SAM surface, whereas they were well dispersed on the MUT‐SAM surface and localized on the MUA‐SAM surface. The results suggest that interactions between AuNPs differ according to the degree of peeling of citrate‐layer‐capped AuNPs. The degree of peeling, which is related to both the surface randomness of the SAMs and the functional characteristics of the terminal group of each SAM, was discussed on the basis of scanning tunneling microscopy observations, X‐ray photoelectron spectroscopic analyses, and contact angle measurements. Our study shows that AuNP patterns can be controlled by changing the terminal group of the alkyl thiol SAM on a Au(111) surface.}, number={11}, journal={SURFACE AND INTERFACE ANALYSIS}, author={Zahid, Ali A. S. M. and Hanif, Md. A. and Lee, Insup and Islam, Md. Akherul and Hahn, Jae R.}, year={2019}, month={Nov}, pages={1102–1112} }
 @article{abu hanif_lee_akter_islam_zahid_sapkota_hahn_2019, title={Enhanced Photocatalytic and Antibacterial Performance of ZnO Nanoparticles Prepared by an Efficient Thermolysis Method}, volume={9}, ISSN={["2073-4344"]}, DOI={10.3390/catal9070608}, abstractNote={ZnO nanoparticles (ZnO-NPs) were synthesized by a straightforward modified thermal method using only one chemical: zinc acetate dihydrate. The process is environmentally safer than other methods because it does not involve other chemicals or a catalyst, acid, or base source. X-ray diffraction analysis indicated that the ZnO-NPs crystallize in the hexagonal wurtzite structure. The UV–vis absorption spectra revealed a marked redshift, which is critical for enhanced photocatalytic activity. We used methylene blue for photocatalytic activity tests and found an excellent degradation percentage (99.7%) within a short time (80 min). The antibacterial activity of the synthesized ZnO-NPs was tested against Escherichia coli at different concentrations of ZnO-NPs. The analysis revealed that the minimum inhibitory concentration (MIC) of the ZnO-NPs against E. coli was 30–50 μg/mL. Our ZnO-NPs were found to be more effective than previously reported ZnO-NPs synthesized via other methods.}, number={7}, journal={CATALYSTS}, author={Abu Hanif, Md and Lee, Insup and Akter, Jeasmin and Islam, Md Akherul and Zahid, Ali A. S. M. and Sapkota, Kamal Prasad and Hahn, Jae Ryang}, year={2019}, month={Jul} }
 @article{jang_shin_abbas_hahn_kang_2019, title={Orientation-specific switching of inelastic electron tunneling in an oxygen-pyridine complex adsorbed onto an Ag(110) surface}, volume={151}, ISSN={["1089-7690"]}, DOI={10.1063/1.5110545}, abstractNote={Here, we report the development of a molecular rotary switch (a "stator-rotor" consisting of a single oxygen molecule as a stator and a single pyridine molecule as a rotor) on a silver surface. The pyridine molecule was bonded to the oxygen molecule and was found to rotate to enable "ON" or "OFF" vibrational conductance through the oxygen molecule. Four stable sites around the oxygen molecule were observed, and vibration conductance turned on and off depending on the site at which the pyridine molecule bonded. The spatially resolved mapping of the vibrational change revealed two locations of maximal vibration intensity, separated by ∼3 Å. These positions acted as two conducting channels. The two distinct vibrational energy levels were associated with the switching process. Adsorption-induced electron transfer between the silver layers and the molecules enhanced the local interactions between the molecules. The two vibration modes were excited by resonant tunneling despite substantial interactions between the molecules, which resulted in a decrease in tunneling conductance. An independent pathway exists for the vibrational excitation process by tunneling electrons and intermolecular interactions.}, number={11}, journal={JOURNAL OF CHEMICAL PHYSICS}, author={Jang, Sanghoon and Shin, Taeho and Abbas, Hafiz Ghulam and Hahn, Jae R. and Kang, Hong Seok}, year={2019}, month={Sep} }
 @article{kim_jeong_lee_abu hanif_islam_sapkota_hahn_2019, title={Role of Electronic Structures and Dispersion Interactions in Adsorption Selectivity of Pyrimidine Molecules with a Si(5512) Surface}, volume={123}, ISSN={["1932-7455"]}, DOI={10.1021/acs.jpcc.9b03520}, abstractNote={We show that the resonance energy and dispersion interactions (DIs) are critical factors in determining the selectivity and configuration in the reaction of pyrimidine molecules with a silicon surface. The atomic structures of the pyrimidine molecules after they reacted with a Si(5 5 12)–2 × 1 surface were studied. Binding configurations of the pyrimidines were distinct from those of other molecules with N lone-pair electrons and aromaticity. The pyrimidine molecules were adsorbed to produce two σ bonds to silicon with N2 and C5 on the adatom row (Adr) and honeycomb chain (Hnc) sites and with C1 and C4 on the dimer row (Dmr) and the tetramer row (Ttr) sites. The reactions occurred via a [4 + 2]-type cycloaddition to produce planar-type configurations with loss of aromaticity. That is, the atoms of the aromatic ring of pyrimidine form chemical bonds with silicon atoms, which is in contrast to the adsorption behaviors reported for other N-containing aromatic molecules. When pyrimidine is adsorbed, its molec...}, number={32}, journal={JOURNAL OF PHYSICAL CHEMISTRY C}, author={Kim, Gyu-Hyeong and Jeong, Sukmin and Lee, Insup and Abu Hanif, Md. and Islam, Md. Akherul and Sapkota, Kamal P. and Hahn, Jae R.}, year={2019}, month={Aug}, pages={19506–19512} }
 @article{shima_hossain_lee_son_hahn_2017, title={Carbon-ZnO core-shell nanospheres: Facile fabrication and application in the visible-light photocatalytic decomposition of organic pollutant dyes}, volume={185}, ISSN={["1879-3312"]}, DOI={10.1016/j.matchemphys.2016.10.007}, abstractNote={We developed a simple thermolysis method for fabricating effective photocatalysts for the decomposition of organic pollutants under sunlight. Zinc oxide-deposited carbon spheres (ZDCS) were prepared via a one-pot process in a solvent- and catalyst-free environment. The ZDCS composite exhibited a strong light absorption band across the whole visible range, a very good dispersion concentration (1.84 mg/mL) in organic solvents without the need for surfactants, ionic liquids, or stabilizers, and a high electrical conductivity (∼1300 S/m). These materials were shown to be useful for decomposing organic pollutants under sunlight. The reaction time (105 min), degradation percentage (98.2%), and recycling performance suggested that ZDCS act as an excellent photocatalyst under visible light illumination for the decomposition of methylene blue. The enhanced physicochemical properties of the ZDCS are due to the covalent interaction between the carbon core and ZnO outer layer, which increases the lifetime of photo-generated charge carriers.}, journal={MATERIALS CHEMISTRY AND PHYSICS}, author={Shima, Hossain and Hossain, Muhammad M. and Lee, Insup and Son, Seungbae and Hahn, Jae R.}, year={2017}, month={Jan}, pages={73–82} }
 @article{lee_son_shin_hahn_2017, title={Direct observation of the conformational transitions of single pyridine molecules on a Ag(110) surface induced by long-range repulsive intermolecular interactions}, volume={146}, ISSN={["1089-7690"]}, DOI={10.1063/1.4973379}, abstractNote={The transition between two conformations of pyridine molecules adsorbed on a Ag(110) surface at 13 K was investigated by performing single-molecule manipulation at a very low coverage and the track-imaging of pyridines for various surface coverages using a variable low-temperature scanning tunneling microscope. A single tilted conformer was converted to an upright conformer when another coadsorbed tilted pyridine molecule approached to within ∼2 nm. The conversion probability depends on the molecular separation. The tilted conformers that are prevalent at a very low coverage were converted to upright conformers with an increasing surface coverage. The minimum molecular separation before this transition is induced was determined to be 2.2 nm using molecular track-imaging and statistical analysis of the pyridine separation as a function of the molecular coverage. The conformation transition was attributed to substrate-mediated long-range repulsive interactions between the pyridine molecules, which are produced by charge redistribution that occurs upon pyridine adsorption on the silver surface.}, number={1}, journal={JOURNAL OF CHEMICAL PHYSICS}, author={Lee, Insup and Son, Seungbae and Shin, Taeho and Hahn, Jae R.}, year={2017}, month={Jan} }
 @article{hossain_son_hahn_2017, title={In Situ Solution Process for Fabricating Thermally and Mechanically Stable Highly Conductive ZnO-CNT Fiber Composites}, volume={131}, ISSN={["1898-794X"]}, DOI={10.12693/aphyspola.131.124}, abstractNote={In Situ Solution Process for Fabricating Thermally and Mechanically Stable Highly Conductive ZnO–CNT Fiber Composites M.M. Hossain, S.B. Son and J.R. Hahna,c,∗ Department of Chemistry and Bioactive Material Sciences, Research Institute of Physics and Chemistry, Chonbuk National University, Jeonju 561-756, Korea Jeonju Center, Korea Basic Science Institute, Jeonju 561-756, Republic of Korea Textile Engineering, Chemistry and Science, North Carolina State University, 2401 Research Dr., Raleigh, NC 27695-8301, USA}, number={1}, journal={ACTA PHYSICA POLONICA A}, author={Hossain, M. M. and Son, S. B. and Hahn, J. R.}, year={2017}, month={Jan}, pages={124–132} }
 @article{hossain_shima_lee_hahn_2017, title={In situ preparation of graphene-ZnO composites for enhanced graphite exfoliation and graphene-nylon-6 composite films}, volume={134}, ISSN={["1097-4628"]}, DOI={10.1002/app.45034}, abstractNote={An effective method for the fabrication of graphene-ZnO nanoparticle (GZN) composites has been developed. GZN composites with high electrical conductivity (18,607 S/m) are prepared in situ from graphite-ZnO composites. The GZN composites also exhibit visible-light absorption and enable the effective exfoliation of graphite. The presence of the ZnO nanoparticles assists the exfoliation of graphite and enables the preparation of solutions of highly dispersed and concentrated graphene sheets (2.7 mg/mL) that exhibit high electrical conductivity without reduction (40,404 S/m). A solution of graphene sheets was used to produce a graphene-nylon-6 film with an excellent Young's modulus (3 GPa) and a high tensile strength (109 MPa). An exclusive mechanism was proposed for the improvement of mechanical properties of the nylon-6 composite film. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45034.}, number={27}, journal={JOURNAL OF APPLIED POLYMER SCIENCE}, author={Hossain, Muhammad Mohsin and Shima, Hossain and Lee, Insup and Hahn, Jae Ryang}, year={2017}, month={Jul} }
 @article{hossain_shima_son_hahn_2016, title={In situ fabrication of a thermally stable and highly porous conductive solar light-driven ZnO-CNT fiber photocatalyst}, volume={6}, ISSN={["2046-2069"]}, DOI={10.1039/c6ra08190h}, abstractNote={A novel method to produce composite fiber photocatalysts consisting of ZnO nanoparticles and carbon nanotube fibers (ZnO–CNTFs) with high thermal stability and porosity was developed by catalyst-free recrystallization followed by thermal decomposition. The CNTFs were strongly bound to sheet-stacks of ZnO nanoparticles, and these sheet-stacks were shown to be highly porous. Oxygen vacancies in the ZnO nanoparticles play a role in the robust interactions between ZnO and the CNTFs. Several functional properties of the ZnO–CNTF composite were characterized: (a) electrical conductivity was measured to be 78 S cm−1 and 139 S cm−1 depending on the probe position, (b) thermal stability up to 875 °C, (c) photoactivity between 300 nm and 2100 nm, and a much stronger load bearing force than the pristine CNTFs. These enhanced mechanical, electrical, thermal, and optical properties of the ZnO–CNTF composite, as well as its radial breathing mode, were likely generated by the strong interactions between ZnO and CNTF. These enhanced characteristics lead to an excellent photocatalytic performance of the ZnO–CNTF composite under sunlight; the shorter degradation time (75 min), the high degradation percentage (97.6%), excellent recycle performance (93.5%) and number (12) with the amount (135 mg) to decompose methylene blue (100 mL, 0.25 mg mL−1).}, number={75}, journal={RSC ADVANCES}, author={Hossain, Muhammad M. and Shima, Hossain and Son, Seungbae and Hahn, Jae R.}, year={2016}, pages={71450–71460} }
 @article{hossain_shima_ku_hahn_2015, title={Nanoforests composed of ZnO/C core-shell hexagonal nanosheets: fabrication and growth in a sealed thermolysis reactor and optical properties}, volume={50}, ISSN={["1573-4803"]}, DOI={10.1007/s10853-014-8569-5}, number={1}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Hossain, Muhammad Mohsin and Shima, Hossain and Ku, Bon-Cheol and Hahn, Jae Ryang}, year={2015}, month={Jan}, pages={93–103} }
 @article{hossain_ku_hahn_2015, title={Synthesis of an efficient white-light photocatalyst composite of graphene and ZnO nanoparticles: Application to methylene blue dye decomposition}, volume={354}, ISSN={["1873-5584"]}, DOI={10.1016/j.apsusc.2015.01.191}, abstractNote={A graphene–ZnO nanoparticle composite was fabricated by an in situ solvothermal process at low temperatures without catalytic assistance. The as-prepared composite absorbs light at an extended range of wavelengths from the visible to the near IR (400–1665 nm), efficiently absorbs high-intensity light in the near IR region, and exhibits high electrical conductivity. The highly porous structure of aggregated ZnO nanoparticles on the graphene surface enables these particles to absorb dye and degrade it. X-ray photoelectron spectroscopy analysis suggests that a number of oxygen vacancy defects are created in the ZnO matrix and that Zn atoms are chemically bonded to CO groups at the relatively amorphous sites of the graphene surface. Raman spectroscopy analysis indicates a strong interaction between the graphene surface and ZnO nanoparticles. Further analyses using scanning electron microscopy, transmission electron microscopy, UV–visible–near-IR absorption, band gap calculations, electrical conductivity measurements, and photocatalysis show that the incorporation of graphene with ZnO nanoparticles narrows the band gap of ZnO, facilitates an extended range of light absorption, improves the electrical conductivity of ZnO, creates oxygen vacancy defects in the ZnO crystal, and enhances stability against photocorrosion.}, journal={APPLIED SURFACE SCIENCE}, author={Hossain, Muhammad Mohsin and Ku, Bon-Cheol and Hahn, Jae Ryang}, year={2015}, month={Nov}, pages={55–65} }
 @article{hossain_park_hahn_ku_2014, title={High yield and high concentration few-layer graphene sheets using solvent exfoliation of graphite with pre-thermal treatment in a sealed bath}, volume={123}, ISSN={["1873-4979"]}, DOI={10.1016/j.matlet.2014.03.024}, abstractNote={We developed an efficient method for exfoliating pristine graphite in an organic solvent to produce a high yield (14%) and high concentration (5.25 mg/mL) of well-dispersed mono-, bi-, and multi-layered graphene sheets. Pre-thermal activation of pristine graphite at 900 °C in a sealed stainless steel bath under high pressure, followed by sonication in a solvent of 1-methyl-2-pyrrolidinone at elevated temperatures produced a solution of homogeneous, well-dispersed, defect-free, and non-oxidized graphene. The resulting electrical conductivities of the graphene sheets were high, up to 849 S/cm.}, journal={MATERIALS LETTERS}, author={Hossain, Muhammad Mohsin and Park, Ok-Kyung and Hahn, Jae Ryang and Ku, Bon-Cheol}, year={2014}, month={May}, pages={90–92} }
 @article{shima_hossain_hahn_2014, title={Highly dispersed graphene ribbons produced from ZnO-C core-shell nanorods and their use as a filler in polyimide composites}, volume={4}, ISSN={["2046-2069"]}, DOI={10.1039/c4ra06782g}, abstractNote={Long and few-layer thickness graphene ribbons (GRs) were fabricated through an efficient process from a well-ordered array of ZnO–C core–shell hexagonal nanorods that were formed by thermally heating zinc acetate dihydrate in a sealed chamber. The lengths and widths of the GRs were as high as ∼50 μm and 100–400 nm, respectively. The GRs could be highly dispersed (∼2 mg mL−1) in 1-methyl-2-pyrrolidinone and exhibited a good electrical conductivity (5107 S m−1). The highly dispersed and highly conductive GRs were applied to the fabrication of a GR–polyimide composite film that exhibited good mechanical properties while preserving the film transparency.}, number={78}, journal={RSC ADVANCES}, author={Shima, Hossain and Hossain, Muhammad Mohsin and Hahn, Jae Ryang}, year={2014}, pages={41204–41211} }