@article{kumar_bhardwaj_kaushik_2021, title={Luminescence Behavior of the Ba2HfF8:Dy3+/Sm3+ Nanophosphor for White Light-Emitting Applications}, volume={3}, ISSN={["2637-6113"]}, DOI={10.1021/acsaelm.1c00184}, abstractNote={Lanthanide (Ln)-doped inorganic materials are widely used in X-ray scintillation, enabling luminescence in the UV to near-infrared region with average lifetime ranging from nanosecond to hours. Flu...}, number={5}, journal={ACS APPLIED ELECTRONIC MATERIALS}, author={Kumar, Vineet and Bhardwaj, Vinay and Kaushik, Ajeet}, year={2021}, month={May}, pages={2261–2267} }
 @article{kumar_o'donnell_slang_maggard_wang_2019, title={Harnessing Plasmon-Induced Hot Carriers at the Interfaces with Ferroelectrics}, volume={7}, ISSN={["2296-2646"]}, DOI={10.3389/fchem.2019.00299}, abstractNote={This article reviews the scientific understanding and progress of interfacing plasmonic particles with ferroelectrics in order to facilitate the absorption of low-energy photons and their conversion to chemical fuels. The fundamental principles of hot carrier generation and charge injection are described for semiconductors interfaced with metallic nanoparticles and immersed in aqueous solutions, forming a synergistic juncture between the growing fields of plasmonically-driven photochemistry and semiconductor photocatalysis. The underlying mechanistic advantages of a metal-ferroelectric vs. metal-nonferroelectric interface are presented with respect to achieving a more optimal and efficient control over the Schottky barrier height and charge separation. Notable recent examples of using ferroelectric-interfaced plasmonic particles have demonstrated their roles in yielding significantly enhanced photocurrents as well as in the photon-driven production of molecular hydrogen. Notably, plasmonically-driven photocatalysis has been shown to occur for photon wavelengths in the infrared range, which is at lower energies than typically possible for conventional semiconductor photocatalysts. Recent results thus demonstrate that integrated ferroelectric-plasmonic systems represent a potentially transformative concept for use in the field of solar energy conversion.}, number={299}, journal={Frontiers in Chemistry}, author={Kumar, V and O'Donnell, S.C. and Slang, D.L. and Maggard, P.A. and Wang, G.}, year={2019}, month={May}, pages={1–19} }
 @article{kumar_o'donnell_zoellner_martinez_wang_maggard_2019, title={Interfacing Plasmonic Nanoparticles with Ferroelectrics for Hot-Carrier-Driven Photocatalysis: Impact of Schottky Barrier Height}, volume={2}, ISSN={["2574-0962"]}, DOI={10.1021/acsaem.9b01682}, abstractNote={Emergent strategies for efficient solar energy conversion have focused on ways to harness photons in the lower-energy range of sunlight that cannot be utilized by conventional semiconductor photocatalyst systems. Recent research has demonstrated that interfaced plasmonic–ferroelectric particles represent a promising strategy for the utilization of near-infrared (NIR) light owing to the possibility of the more efficient injection of hot charge carriers from noble metal nanoparticles. Described herein, platinum-end-capped gold nanorods (AuNRs) function as antennae to absorb low-energy NIR photons to generate hot electrons that can be injected into ferroelectric PbZrxTi1–xO3 (PZT; x = 0.48, 0.50, 0.52, 0.54, 0.56, and 0.60) and drive the reduction of water to molecular hydrogen at its surfaces. As an aqueous suspension, the interfaced AuNR-PZT particles exhibited maximal photocatalytic rates for hydrogen formation under a 976 nm diode laser (powder density = 2.0 W cm–2) for the 52% Zr (x = 0.52) composition ...}, number={10}, journal={ACS APPLIED ENERGY MATERIALS}, author={Kumar, Vineet and O'Donnell, Shaun and Zoellner, Brandon and Martinez, Jhon and Wang, Gufeng and Maggard, Paul A.}, year={2019}, month={Oct}, pages={7690–7699} }
 @article{ortiz_zoellner_kumar_janelli_tang_maggard_wang_2018, title={Composite Ferroelectric and Plasmonic Particles for Hot Charge Separation and Photocatalytic Hydrogen Gas Production}, volume={1}, ISSN={["2574-0962"]}, DOI={10.1021/acsaem.8b00772}, abstractNote={Plasmonic nanoparticles are excellent light absorbers for harvesting solar energy, resulting in hot electrons that can be utilized in photocatalytic hydrogen production. However, the hot electrons generated in a localized surface plasmon resonance process have a very short lifetime and are challenging to use efficiently. Herein, using near IR light irradiation, we show that by combining gold nanorods (AuNRs) with ferroelectric PbTiO3 particles that possess a large remanent electric dipole moment, hot charges generated on plasmonic particles can be injected into ferroelectric materials and drive the photocatalysis reaction. Compared to metallic Pt-end-capped AuNRs, the efficiency of using hot electrons for photocatalytic reactions is enhanced for the composite catalyst, which improves the light-to-chemical energy conversion efficiencies by about 1 order of magnitude for the same amount of plasmonic particles being used.}, number={9}, journal={ACS APPLIED ENERGY MATERIALS}, author={Ortiz, Nathalia and Zoellner, Brandon and Kumar, Vineet and Janelli, Tara and Tang, Shuli and Maggard, Paul A. and Wang, Gufeng}, year={2018}, month={Sep}, pages={4606–4616} }
 @article{kumar_zoellner_maggard_wang_2018, title={Effect of doping Ge into Y2O3:Ho,Yb on the green-to-red emission ratio and temperature sensing}, volume={47}, ISSN={["1477-9234"]}, DOI={10.1039/c8dt02216j}, abstractNote={The Ge-doped Y2O3:Ho,Yb phosphor tunes the G/R ratio, and the G/R ratio has a higher absolute temperature sensitivity.}, number={32}, journal={DALTON TRANSACTIONS}, author={Kumar, Vineet and Zoellner, Brandon and Maggard, Paul A. and Wang, Gufeng}, year={2018}, month={Aug}, pages={11158–11165} }
 @article{kumar_wang_2018, title={Tuning green-to-red ratio of Ho3+/Yb3+ activated GdPO4 upconversion luminescence through Eu3+ doping}, volume={199}, ISSN={["1872-7883"]}, DOI={10.1016/j.jlumin.2018.03.037}, abstractNote={The upconverison photoluminescence of co-doped Ho and Eu in GdPO4:Yb was studied. GdPO4:Ho3+(1%),Yb3+(10%) phosphors with varying Eu3+ fractions from 0% to 5% were synthesized using solid-state reaction and characterized using X-ray diffraction, diffuse reflectance, and upconversion (UC) photoluminescence. The co-doped Ho and Eu showed negligible energy transfer between their visible emission states (Ho 5F4/5S2 and Eu 5D0) so the two luminophores can be selectively excited. However, the presence of 5% Eu in the host lattice enhances the green-to-red emission ratio by 25 times from 0.04 to 1.0 under near infrared (NIR) excitation. It is suggested that the energy transfer from Ho intermediates states to Eu ground state (from Ho 5I6 and 5I7 to Eu 7F6) tunes the Ho emission G/R ratio. These phosphor particles are suitable for long-term single particle tracking and fluorescent labels.}, journal={JOURNAL OF LUMINESCENCE}, author={Kumar, Vineet and Wang, Gufeng}, year={2018}, month={Jul}, pages={188–193} }