@article{haribal_iftikhar_tong_rayer_sanderson_li_neal_2024, title={Technoeconomic and Emissions Analysis of the Hybrid Redox Process for the Production of Acetic Acid with CO<sub>2</sub> Utilization}, volume={3}, ISSN={["2366-7486"]}, DOI={10.1002/adsu.202300453}, abstractNote={Abstract}, journal={ADVANCED SUSTAINABLE SYSTEMS}, author={Haribal, Vasudev and Iftikhar, Sherafghan and Tong, Andrew and Rayer, Aravind and Sanderson, Corry and Li, Fanxing and Neal, Luke}, year={2024}, month={Mar} }
 @article{rahmanian_pirzada_barbieri_iftikhar_li_khan_2023, title={Mechanically robust, thermally insulating and photo-responsive aerogels designed from sol-gel electrospun PVP-TiO2 nanofibers}, volume={32}, ISSN={["2352-9407"]}, url={https://doi.org/10.1016/j.apmt.2023.101784}, DOI={10.1016/j.apmt.2023.101784}, abstractNote={We present a robust approach for fabricating polyvinylpyrrolidone (PVP)-titania (TiO2) nanofibrous aerogels (NFA) with multifunctional and triggered performances. These low density (∼ 10 mg cm−3) 3D self-supported aerogels having an intrinsically lamellar porous structure (> 99% porosity) are created via solid templating of sol-gel electrospun PVP-TiO2 hybrid nanofibers. The photocatalytic activity of TiO2 allows for on-demand application wherein the aerogel exhibits antibacterial properties upon UV exposure to bacteria such as Escherichia coli and Salmonella enterica. Significantly, while the aerogel sorbs common volatile organic components (VOCs) or oil due to its innate porosity, exposure of the aerogel to ultraviolet (UV) radiation leads to their decomposition. The PVP-TiO2 NFA exhibits a low thermal conductivity (0.062 W m−1 K−1) together with considerable mechanical flexibility up to strains of 50% with >90% recovery, without the need for post-processing. The photo-responsive attributes combined with mechanical resilience, oleophilicity and thermal insulation properties render these aerogels viable candidates for a diverse range of applications. We discuss such property enhancements in terms of the interaction between PVP and TiO2 and aerogel microstructure.}, journal={APPLIED MATERIALS TODAY}, author={Rahmanian, Vahid and Pirzada, Tahira and Barbieri, Eduardo and Iftikhar, Sherafghan and Li, Fanxing and Khan, Saad A.}, year={2023}, month={Jun} }
 @article{wang_gao_krzystowczyk_iftikhar_dou_cai_wang_ruan_ye_li_2022, title={High-throughput oxygen chemical potential engineering of perovskite oxides for chemical looping applications}, volume={2}, ISSN={["1754-5706"]}, url={https://doi.org/10.1039/D1EE02889H}, DOI={10.1039/d1ee02889h}, abstractNote={Integrating DFT, machine learning and experimental verifications, a high-throughput screening scheme is performed to rationally engineer the redox properties of SrFeO3−δ based perovskites for chemical looping applications.}, number={4}, journal={ENERGY & ENVIRONMENTAL SCIENCE}, publisher={Royal Society of Chemistry (RSC)}, author={Wang, Xijun and Gao, Yunfei and Krzystowczyk, Emily and Iftikhar, Sherafghan and Dou, Jian and Cai, Runxia and Wang, Haiying and Ruan, Chongyan and Ye, Sheng and Li, Fanxing}, year={2022}, month={Feb} }
 @article{iftikhar_martin_gao_yu_wang_wu_li_2022, title={LaNixFe1−xO3 as flexible oxygen or carbon carriers for tunable syngas production and CO2 utilization}, volume={416}, ISSN={0920-5861}, url={http://dx.doi.org/10.1016/j.cattod.2022.07.022}, DOI={10.1016/j.cattod.2022.07.022}, abstractNote={The current study reports LaFe1−xNixO3−δ redox catalysts as flexible oxygen or carbon carriers for CO2 utilization and tunable production of syngas at relatively low temperatures (∼700 °C), in the context of a hybrid redox process. Specifically, perovskite-structured LaFe1−xNixO3−δ with seven different compositions (x = 0.4–1) were prepared and investigated. Cyclic experiments under alternating methane and CO2 flows indicated that all the samples exhibited favorable reactive performance: CH4 and CO2 conversions varied between 85% and 98% and 70–88%, respectively. While H2/CO ratio from Fe-rich redox catalysts was ~2.3:1 in the methane conversion step, Ni-rich catalysts produced a concentrated (~ 93.7 vol%) hydrogen stream via methane cracking. The flexibility of LaFe1−xNixO3−δ to produce syngas (or hydrogen) with tunable compositions was found to be governed by the iron/nickel (Fe/Ni) ratio. Redox catalysts with higher Fe contents act as a lattice oxygen carrier via chemical looping partial oxidation (CLPOx) of methane whereas those with higher Ni contents function as a carbon carrier via chemical looping methane cracking (CLMC) scheme. XRD analysis and temperature-programmed reactions revealed that both types of catalysts involve the formation of La2O3 and Ni0 /Ni-Fe phases under the methane environment. The ability to re-incorporate La2O3 and Ni/Fe into a perovskite structure gives rise to oxygen-carrying capacity whereas stable Ni0 or Ni/Fe phases would catalyze methane cracking without lattice oxygen exchange in the reaction cycles. Temperature programmed oxidation and Raman spectroscopy indicated the presence of graphitic and amorphous carbon species, which were effectively gasified by CO2 to produce concentrated CO. Stability tests over LaFe0.5Ni0.5O3 and LaNiO3 revealed that the redox performance was stable over a span of 50 cycles.}, journal={Catalysis Today}, publisher={Elsevier BV}, author={Iftikhar, Sherafghan and Martin, William and Gao, Yunfei and Yu, Xinbin and Wang, Iwei and Wu, Zili and Li, Fanxing}, year={2022}, month={Jul} }
 @article{iftikhar_martin_wang_liu_gao_li_2022, title={Ru-promoted perovskites as effective redox catalysts for CO2 splitting and methane partial oxidation in a cyclic redox scheme}, volume={11}, ISSN={["2040-3372"]}, url={https://doi.org/10.1039/D2NR04437D}, DOI={10.1039/d2nr04437d}, abstractNote={The current study reports AxA′1−xByB′1−yO3−δ perovskite redox catalysts (RCs) for CO2-splitting and methane partial oxidation (POx) in a cyclic redox scheme.}, journal={NANOSCALE}, author={Iftikhar, Sherafghan and Martin, William and Wang, Xijun and Liu, Junchen and Gao, Yunfei and Li, Fanxing}, year={2022}, month={Nov} }
 @article{gu_gao_iftikhar_li_2021, title={Ce stabilized Ni-SrO as a catalytic phase transition sorbent for integrated CO2 capture and CH4 reforming}, volume={12}, ISSN={["2050-7496"]}, url={https://doi.org/10.1039/D1TA09967A}, DOI={10.1039/d1ta09967a}, abstractNote={Ce stabilized Ni–SrO was proposed as a bifunctional catalyst-sorbent. CeO2 promoted a complex carbonation/decarbonation pathway to solve the sorbent stability challenges and facilitated syngas generation with tunable compositions.}, journal={JOURNAL OF MATERIALS CHEMISTRY A}, publisher={Royal Society of Chemistry (RSC)}, author={Gu, Haiming and Gao, Yunfei and Iftikhar, Sherafghan and Li, Fanxing}, year={2021}, month={Dec} }
 @article{iftikhar_aslam_ali_akhtar_2021, title={Comparison among various configurations of hybrid distillation-membrane setups for the energy efficiency improvement of bioethanol distillery: a simulation study}, volume={11}, ISSN={["1097-4660"]}, DOI={10.1002/jctb.6969}, abstractNote={Abstract}, journal={JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY}, author={Iftikhar, Sherafghan and Aslam, Zaheer and Ali, Usman and Akhtar, Adnan}, year={2021}, month={Nov} }
 @article{iftikhar_jiang_gao_liu_gu_neal_li_2021, title={LaNixFe1-xO3-delta as a Robust Redox Catalyst for CO2 Splitting and Methane Partial Oxidation}, volume={35}, ISSN={["1520-5029"]}, DOI={10.1021/acs.energyfuels.1c02258}, abstractNote={The current study reports LaNi0.5Fe0.5O3−δ as a robust redox catalyst for CO2 splitting and methane partial oxidation at relatively low temperatures (∼700 °C) in the context of a hybrid redox process. Specifically, perovskite-structured LaNixFe1–xO3−δ (LNFs) with nine different compositions (x = 0.05–0.5) were prepared and investigated. Among the samples evaluated, LaNi0.4Fe0.6O3−δ and LaNi0.5Fe0.5O3−δ showed superior redox performance, with ∼90% CO2 and methane conversions and >90% syngas selectivity. The standalone LNFs also demonstrated performance comparable to that of LNF promoted by mixed conductive Ce0.85Gd0.1Cu0.05O2−δ (CGCO). Long-term testing of LaNi0.5Fe0.5O3−δ indicated that the redox catalyst gradually loses its activity over repeated redox cycles, amounting to approximately 0.02% activity loss each cycle, averaged over 500 cycles. This gradual deactivation was found to be reversible by deep oxidation with air. Further characterizations indicated that the loss of activity resulted from a slow accumulation of iron carbide (Fe3C and Fe5C2) phases, which cannot be effectively removed during the CO2 splitting step. Reoxidation with air removed the carbide phases, increased the availability of Fe for the redox reactions via solid-state reactions with La2O3, and decreased the average crystallite size of La2O3. Reactivating the redox catalyst periodically, e.g., once every 40 cycles, was shown to be highly effective, as confirmed by operating the redox catalyst over 900 cumulative cycles while maintaining satisfactory redox performance.}, number={17}, journal={ENERGY & FUELS}, author={Iftikhar, Sherafghan and Jiang, Qiongqiong and Gao, Yunfei and Liu, Junchen and Gu, Haiming and Neal, Luke and Li, Fanxing}, year={2021}, month={Sep}, pages={13921–13929} }
 @article{wang_gao_wang_cai_chung_iftikhar_wang_li_2021, title={Liquid Metal Shell as an Effective Iron Oxide Modifier for Redox-Based Hydrogen Production at Intermediate Temperatures}, volume={11}, ISSN={["2155-5435"]}, url={https://doi.org/10.1021/acscatal.1c02102}, DOI={10.1021/acscatal.1c02102}, abstractNote={This study reports molten metals (bismuth, indium, and tin) as effective modifiers for iron-based redox catalysts in the context of chemical looping-based hydrogen production at intermediate temperatures (450–650 °C) from low-calorific-value waste gas (e.g., blast furnace gas). The effects of the bismuth promoter on both the surface and bulk properties of iron oxides were studied in detail. Transmission electron microscopy and energy-dispersive spectroscopy (TEM-EDS), low-energy ion scattering (LEIS), Raman spectroscopy, and 18O2 exchange experiment revealed that the bismuth modifier forms an overlayer covering the bulk iron (oxides), leading to better anti-coking properties compared to reference La0.8Sr0.2FeO3- and Ce0.9Gd0.1O2-supported iron oxides. The Bi-modified sample also exhibited improved anti-sintering properties and high redox activity, resulting in a 4-fold increase in oxygen capacity compared to pristine Fe2O3 (28.9 vs 6.4 wt %) under a cyclic redox reaction at 550 °C. Meanwhile, a small amount of bismuth is doped into the iron oxide structure to effectively enhance its redox properties by lowering the oxygen vacancy formation energy (from 3.1 to 2.1 eV) and the energy barrier for vacancy migration, as confirmed by the experimental results and density functional theory (DFT) calculations. Reactive testing indicates that Bi-modified redox catalysts are highly active to convert low-calorific-value waste gases such as blast furnace gas. Our study also indicates that this strategy can be generalized to low-melting-point metals such as Bi, In, and Sn for iron oxide modification in chemical looping processes.}, number={16}, journal={ACS CATALYSIS}, publisher={American Chemical Society (ACS)}, author={Wang, Iwei and Gao, Yunfei and Wang, Xijun and Cai, Runxia and Chung, Chingchang and Iftikhar, Sherafghan and Wang, Wei and Li, Fanxing}, year={2021}, month={Aug}, pages={10228–10238} }