Search Results - "Ellingson, Randy J."

Dithieno[3,2‐b:2′,3′‐d]pyrrole Cored p‐Type Semiconductors Enabling 20 % Efficiency Dopant‐Free Perovskite Solar Cells by Zhou, Jie, Yin, Xinxing, Dong, Zihao, Ali, Amjad, Song, Zhaoning, Shrestha, Niraj, Bista, Sandip Singh, Bao, Qinye, Ellingson, Randy J., Yan, Yanfa, Tang, Weihua

“…Organic p‐type semiconductors with tunable structures offer great opportunities for hybrid perovskite solar cells (PVSCs). We report herein two…”
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Reducing Saturation‐Current Density to Realize High‐Efficiency Low‐Bandgap Mixed Tin–Lead Halide Perovskite Solar Cells by Li, Chongwen, Song, Zhaoning, Zhao, Dewei, Xiao, Chuanxiao, Subedi, Biwas, Shrestha, Niraj, Junda, Maxwell M., Wang, Changlei, Jiang, Chun‐Sheng, Al‐Jassim, Mowafak, Ellingson, Randy J., Podraza, Nikolas J., Zhu, Kai, Yan, Yanfa

“…The unsatisfactory performance of low‐bandgap mixed tin (Sn)–lead (Pb) halide perovskite subcells has been one of the major obstacles hindering the progress of…”
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Impact of Processing Temperature and Composition on the Formation of Methylammonium Lead Iodide Perovskites by Song, Zhaoning, Watthage, Suneth C, Phillips, Adam B, Tompkins, Brandon L, Ellingson, Randy J, Heben, Michael J

“…A delicate control of the stoichiometry, crystallographic phase, and grain structure of the photoactive material is typically required to fabricate…”
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Improving the Performance of Formamidinium and Cesium Lead Triiodide Perovskite Solar Cells using Lead Thiocyanate Additives by Yu, Yue, Wang, Changlei, Grice, Corey R., Shrestha, Niraj, Chen, Jing, Zhao, Dewei, Liao, Weiqiang, Cimaroli, Alexander J., Roland, Paul J., Ellingson, Randy J., Yan, Yanfa

“…Formamidinium lead triiodide (FAPbI3) is considered as an alternative to methylammonium lead triiodide (MAPbI3) because of its lower band gap and better…”
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Oxygenated CdS Buffer Layers Enabling High Open‐Circuit Voltages in Earth‐Abundant Cu2BaSnS4 Thin‐Film Solar Cells by Ge, Jie, Koirala, Prakash, Grice, Corey R., Roland, Paul J., Yu, Yue, Tan, Xinxuan, Ellingson, Randy J., Collins, Robert W., Yan, Yanfa

“…Earth‐abundant Cu2BaSnS4 (CBTS) thin films exhibit a wide bandgap of 2.04–2.07 eV, a high absorption coefficient > 104 cm−1, and a p‐type conductivity,…”
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20%-efficient polycrystalline Cd(Se,Te) thin-film solar cells with compositional gradient near the front junction by Li, Deng-Bing, Bista, Sandip S., Awni, Rasha A., Neupane, Sabin, Abudulimu, Abasi, Wang, Xiaoming, Subedi, Kamala K., Jamarkattel, Manoj K., Phillips, Adam B., Heben, Michael J., Poplawsky, Jonathan D., Cullen, David A., Ellingson, Randy J., Yan, Yanfa

“…Bandgap gradient is a proven approach for improving the open-circuit voltages (V OC s) in Cu(In,Ga)Se 2 and Cu(Zn,Sn)Se 2 thin-film solar cells, but has not…”
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Arylammonium-Assisted Reduction of the Open-Circuit Voltage Deficit in Wide-Bandgap Perovskite Solar Cells: The Role of Suppressed Ion Migration by Chen, Cong, Song, Zhaoning, Xiao, Chuanxiao, Awni, Rasha A, Yao, Canglang, Shrestha, Niraj, Li, Chongwen, Bista, Sandip Singh, Zhang, Yi, Chen, Lei, Ellingson, Randy J, Jiang, Chun-Sheng, Al-Jassim, Mowafak, Fang, Guojia, Yan, Yanfa

“…Surface treatment using large alkyl/aryl ammonium cations has demonstrated reduced open-circuit voltage (V OC) deficits in perovskite solar cells (PSCs), but…”
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Impact of Moisture on Photoexcited Charge Carrier Dynamics in Methylammonium Lead Halide Perovskites by Song, Zhaoning, Shrestha, Niraj, Watthage, Suneth C, Liyanage, Geethika K, Almutawah, Zahrah S, Ahangharnejhad, Ramez H, Phillips, Adam B, Ellingson, Randy J, Heben, Michael J

“…Organic–inorganic metal halide perovskites are notoriously unstable in humid environments. While many studies have revealed the morphology and crystal…”
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Employing Overlayers To Improve the Performance of Cu2BaSnS4 Thin Film based Photoelectrochemical Water Reduction Devices by Ge, Jie, Roland, Paul J, Koirala, Prakash, Meng, Weiwei, Young, James L, Petersen, Reese, Deutsch, Todd G, Teeter, Glenn, Ellingson, Randy J, Collins, Robert W, Yan, Yanfa

“…Earth-abundant copper-barium-thiostannate Cu2BaSnS4 (CBTS)-based thin films have recently been reported to exhibit the optoelectronic and defect properties…”
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Synergistic Effects of Lead Thiocyanate Additive and Solvent Annealing on the Performance of Wide-Bandgap Perovskite Solar Cells by Yu, Yue, Wang, Changlei, Grice, Corey R, Shrestha, Niraj, Zhao, Dewei, Liao, Weiqiang, Guan, Lei, Awni, Rasha A, Meng, Weiwei, Cimaroli, Alexander J, Zhu, Kai, Ellingson, Randy J, Yan, Yanfa

“…We show that the cooperation of lead thiocyanate additive and a solvent annealing process can effectively increase the grain size of mixed-cation lead…”
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Multiple Exciton Generation in Colloidal Silicon Nanocrystals by Beard, Matthew C, Knutsen, Kelly P, Yu, Pingrong, Luther, Joseph M, Song, Qing, Metzger, Wyatt K, Ellingson, Randy J, Nozik, Arthur J

“…Multiple exciton generation (MEG) is a process whereby multiple electron−hole pairs, or excitons, are produced upon absorption of a single photon in…”
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Variations in the Quantum Efficiency of Multiple Exciton Generation for a Series of Chemically Treated PbSe Nanocrystal Films by Beard, Matthew C, Midgett, Aaron G, Law, Matt, Semonin, Octavi E, Ellingson, Randy J, Nozik, Arthur J

“…We study multiple exciton generation (MEG) in two series of chemically treated PbSe nanocrystal (NC) films. We find that the average number of excitons…”
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Highly Efficient Multiple Exciton Generation in Colloidal PbSe and PbS Quantum Dots by Ellingson, Randy J, Beard, Matthew C, Johnson, Justin C, Yu, Pingrong, Micic, Olga I, Nozik, Arthur J, Shabaev, Andrew, Efros, Alexander L

“…We report ultra-efficient multiple exciton generation (MEG) for single photon absorption in colloidal PbSe and PbS quantum dots (QDs). We employ transient…”
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PbTe Colloidal Nanocrystals:  Synthesis, Characterization, and Multiple Exciton Generation by Murphy, James E, Beard, Matthew C, Norman, Andrew G, Ahrenkiel, S. Phillip, Johnson, Justin C, Yu, Pingrong, Mićić, Olga I, Ellingson, Randy J, Nozik, Arthur J

“…We report an alternative synthesis and the first optical characterization of colloidal PbTe nanocrystals (NCs). We have synthesized spherical PbTe NCs having a…”
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Multiple Exciton Generation in Films of Electronically Coupled PbSe Quantum Dots by Luther, Joseph M., Beard, Matthew C., Song, Qing, Law, Matt, Ellingson, Randy J., Nozik, Arthur J.

“…We study multiple exciton generation (MEG) in electronically coupled films of PbSe quantum dots (QDs) employing ultrafast time-resolved transient absorption…”
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Few-Atom-Thick Colloidal PbS/CdS Core/Shell Nanosheets by Khan, Simeen, Jiang, Zhoufeng, Premathilka, Shashini M, Antu, Antara, Hu, Jianjun, Voevodin, Andrey A, Roland, Paul J, Ellingson, Randy J, Sun, Liangfeng

“…Emissive PbS/CdS core/shell nanosheets are synthesized using a cation-exchange method. A significant blue-shift of the photoluminescence is observed,…”
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CuSCN as the Back Contact for Efficient ZMO/CdTe Solar Cells by Li, Deng-Bing, Song, Zhaoning, Bista, Sandip S, Alfadhili, Fadhil K, Awni, Rasha A, Shrestha, Niraj, Rhiannon, DeMilt, Phillips, Adam B, Heben, Michael J, Ellingson, Randy J, Yan, Feng, Yan, Yanfa

“…The replacement of traditional CdS with zinc magnesium oxide (ZMO) has been demonstrated as being helpful to boost power conversion efficiency of cadmium…”
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Photoinduced Charge Carrier Generation in a Poly(3-hexylthiophene) and Methanofullerene Bulk Heterojunction Investigated by Time-Resolved Terahertz Spectroscopy by Ai, Xin, Beard, Matthew C, Knutsen, Kelly P, Shaheen, Sean E, Rumbles, Garry, Ellingson, Randy J

“…We report on the ultrafast photoinduced charge separation processes in varying compositions of poly(3-hexylthiophene) (P3HT) blended with the electron acceptor…”
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Rational design of Lewis base molecules for stable and efficient inverted perovskite solar cells by Li, Chongwen, Wang, Xiaoming, Bi, Enbing, Jiang, Fangyuan, Park, So Min, Li, You, Chen, Lei, Wang, Zaiwei, Zeng, Lewei, Chen, Hao, Liu, Yanjiang, Grice, Corey R, Abudulimu, Abasi, Chung, Jaehoon, Xian, Yeming, Zhu, Tao, Lai, Huagui, Chen, Bin, Ellingson, Randy J, Fu, Fan, Ginger, David S, Song, Zhaoning, Sargent, Edward H, Yan, Yanfa

“…Lewis base molecules that bind undercoordinated lead atoms at interfaces and grain boundaries (GBs) are known to enhance the durability of metal halide…”
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Femtosecond IR Study of Excited-State Relaxation and Electron-Injection Dynamics of Ru(dcbpy)2(NCS)2 in Solution and on Nanocrystalline TiO2 and Al2O3 Thin Films by Asbury, John B, Ellingson, Randy J, Ghosh, Hirendra N, Ferrere, Suzanne, Nozik, Arthur J, Lian, Tianquan

“…The photophysics and electron injection dynamics of Ru(dcbpy)2(NCS)2 [dcbpy = (4,4‘-dicarboxy-2,2‘-bipyridine)] (or Ru N3) in solution and adsorbed on…”
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