A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type sem...A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations （DFT） and electrochem ical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocat alytic hydrogen production experiments under a visible light irradiation （A〉420 nm） were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3S and Rh was found to be the best one among the tested ones.展开更多
CdTe is one of the leading materials for low cost,high efficiency thin-film solar cells with a nearly ideal band gap of 1.48 eV.However,its solar to electricity power conversion efficiency(PCE)is hindered by the relat...CdTe is one of the leading materials for low cost,high efficiency thin-film solar cells with a nearly ideal band gap of 1.48 eV.However,its solar to electricity power conversion efficiency(PCE)is hindered by the relatively low open circuit voltage(VOC)due to intrinsic defect related issues.Here,we propose that alloying CdTe with CdSe could possibly improve the solar cell performance by reducing the"ideal"band gap of CdTe to gain more short-circuit current from long-wavelength absorption without sacrificing much VOC.Using the hybrid functional calculation,we find that the minimum band gap of the CdTe1-xSex alloy can be reduced from 1.48 eV at x=0 to 1.39 eV at x=0.32,and most of the change come from the lowering of the conduction band minimum.We also show that the formation of the alloy can improve the p-type doping of CuCdimpurity based on the reduced effective formation energy and nearly constant effective transition energy level,thus possibly enhance VOC,thus PCE.展开更多
The solar cell based on organic-inorganic hybrid halide perovskite is progressing amazingly fast in last decade owing to the robust experimental and theoretical investigations. First-principles calculation is one of t...The solar cell based on organic-inorganic hybrid halide perovskite is progressing amazingly fast in last decade owing to the robust experimental and theoretical investigations. First-principles calculation is one of the crucial ways to understand the nature of the materials and is practically helpful to the development and application of perovskite solar cells. Here, we briefly review the progress of theoretical studies we made in the last few years on the modification of electronic structures of perovskites by varying the composition, configuration, and structure, and the new understandings into the defect properties of halide perovskites for solar cell and optoelectronic applications. These understandings are foundations and new starting points for future investigations. We hope the experience and inspiration gained from these studies encourage more theoretical explorations for new functional perovskite-based materials.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant No.21090341 and 21361140346)the National Basic Research Program(973 Program)of the Ministry of Science and Technology of China(Grant No.2014CB239401)
文摘A novel Sr2CulnO3S oxysulfide p-type semiconductor photocatalyst has been prepared by solid state reaction method and it exhibits intriguing visible light absorption properties with a bandgap of 2.3 eV. The p-type semiconductor character of the synthesized Sr2CuInO3 S was confirmed by Hall efficient measurement and Mott-Schottky plot analysis. First-principles density functional theory calculations （DFT） and electrochem ical measurements were performed to elucidate the electronic structure and the energy band locations. It was found that the as-synthesized Sr2CuInO3S photocatalyst has appreciate conduction and valence band positions for hydrogen and oxygen evolution, respectively. Photocat alytic hydrogen production experiments under a visible light irradiation （A〉420 nm） were carried out by loading different metal and metal-like cocatalysts on Sr2CuInO3S and Rh was found to be the best one among the tested ones.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0700700)the National Natural Science Foundation of China(Grant Nos.51672023,11847043,11634003,and U1530401)the Science Challenge Project(Grant Nos.TZ2016003 and TZ2018004)
文摘CdTe is one of the leading materials for low cost,high efficiency thin-film solar cells with a nearly ideal band gap of 1.48 eV.However,its solar to electricity power conversion efficiency(PCE)is hindered by the relatively low open circuit voltage(VOC)due to intrinsic defect related issues.Here,we propose that alloying CdTe with CdSe could possibly improve the solar cell performance by reducing the"ideal"band gap of CdTe to gain more short-circuit current from long-wavelength absorption without sacrificing much VOC.Using the hybrid functional calculation,we find that the minimum band gap of the CdTe1-xSex alloy can be reduced from 1.48 eV at x=0 to 1.39 eV at x=0.32,and most of the change come from the lowering of the conduction band minimum.We also show that the formation of the alloy can improve the p-type doping of CuCdimpurity based on the reduced effective formation energy and nearly constant effective transition energy level,thus possibly enhance VOC,thus PCE.
基金Project supported by the National Key Research and Development Program of China (Grant No. 2016YFB0700700)the National Natural Science Foundation of China (Grant Nos. 51672023, 11634003, and U1930402)the Creative Talents Plan in CPSF, China (Grant No. BX2018033).
文摘The solar cell based on organic-inorganic hybrid halide perovskite is progressing amazingly fast in last decade owing to the robust experimental and theoretical investigations. First-principles calculation is one of the crucial ways to understand the nature of the materials and is practically helpful to the development and application of perovskite solar cells. Here, we briefly review the progress of theoretical studies we made in the last few years on the modification of electronic structures of perovskites by varying the composition, configuration, and structure, and the new understandings into the defect properties of halide perovskites for solar cell and optoelectronic applications. These understandings are foundations and new starting points for future investigations. We hope the experience and inspiration gained from these studies encourage more theoretical explorations for new functional perovskite-based materials.
