n-type CZ-Si wafers featuring longer minority carrier lifetime and higher tolerance of certain metal contamination can offer one of the best Si-based solar cells. In this study, Si heterojuction （SHJ） solar cells wh...n-type CZ-Si wafers featuring longer minority carrier lifetime and higher tolerance of certain metal contamination can offer one of the best Si-based solar cells. In this study, Si heterojuction （SHJ） solar cells which was fabricated with different wafers in the top, middle and tail positions of the ingot, exhibited a stable high efficiency of〉 22% in spite of the various profiles of the resistivity and lifetime, which demonstrated the high material utilization of n-type ingot. In addition, for effectively converting the sunlight into electrical power, the pyramid size, pyramid density and roughness of surface of the Cz-Si wafer were investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. Furthermore, the dependence of SHJ solar cell open- circuit voltage on the surface topography was discussed, which indicated that the uniformity of surface pyramid helps to improve the open-circuit voltage and conversion efficiency. Moreover, the simulation revealed that the highest efficiency of the SHJ solar cell could be achieved by the wafer with a thickness of 100 μm. Fortunately, over 23% of the conversion efficiency of the SHJ solar cell with a wafer thickness of 100 μm was obtained based on the systematic optimization of cell fabrication process in the pilot production line. Evidently, the large availability of both n-type ingot and thinner wafer strongly supported the lower cost fabrication of high efficiency SHJ solar cell.展开更多
In this paper, the electrical parameters of Au/n-Si （MS） and Au/Si3N4/n-Si （MIS） Schottky diodes are obtained from the forward bias current-voltage （I-V） and capacitance-voltage （C-V） measurements at room temp...In this paper, the electrical parameters of Au/n-Si （MS） and Au/Si3N4/n-Si （MIS） Schottky diodes are obtained from the forward bias current-voltage （I-V） and capacitance-voltage （C-V） measurements at room temperature. Experimental results show that the rectifying ratios of the MS and MIS diodes at ± 5 V are found to be 1.25 ×103 and 1.27 ×104, respectively. The main electrical parameters of the MS and MIS diodes, such as the zero-bias barrier height （rbBo） and ideality factor （n）, are calculated to be 0.51 eV （I-V）, 0.53 eV （C-V）, and 4.43, and 0.65 eV （I-V）, 0.70 eV （C-V）, and 3.44, respectively. In addition, the energy density distribution profile of the interface states （Nss） is obtained from the forward bias I-V, and the series resistance （Rs） values for the two diodes are calculated from Cheung＇s method and Ohm＇s law.展开更多
n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.0...n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极具有优异的稳定性和PEC水氧化活性,具有相对低的OER起始电位(相对于可逆氢电极电势(RHE)仅为0.938 V),并且在1.23 V vs.RHE电位时具有较高的光电流密度(33.1 m A·cm^(-2)),显著优于Ni/p^(+)n-Si光阳极。工作证明了Fe在Ni层的掺杂会在Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si界面处产生较大的能带弯曲,促进界面电荷分离。此外,Co的加入会产生丰富的Ni^(3+)和氧空位(Ov),作为活性位点可以加速OER动力学过程,协同促进PEC过程中的水氧化的活性。令人鼓舞的是,通过将Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极连接到廉价的硅太阳能电池上,所制备的集成光伏/PEC(PV/PEC)器件实现了无偏压下高达12.0%的太阳制氢能量转换效率。这项工作提供了一种简单的方法来设计高效、稳定的n-Si基光阳极,并对其构效关系有了深刻的理解;这种方法制备的材料在集成低成本PV/PEC器件用于无辅助太阳能驱动水分解方面具有巨大的潜力。展开更多
文摘n-type CZ-Si wafers featuring longer minority carrier lifetime and higher tolerance of certain metal contamination can offer one of the best Si-based solar cells. In this study, Si heterojuction （SHJ） solar cells which was fabricated with different wafers in the top, middle and tail positions of the ingot, exhibited a stable high efficiency of〉 22% in spite of the various profiles of the resistivity and lifetime, which demonstrated the high material utilization of n-type ingot. In addition, for effectively converting the sunlight into electrical power, the pyramid size, pyramid density and roughness of surface of the Cz-Si wafer were investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. Furthermore, the dependence of SHJ solar cell open- circuit voltage on the surface topography was discussed, which indicated that the uniformity of surface pyramid helps to improve the open-circuit voltage and conversion efficiency. Moreover, the simulation revealed that the highest efficiency of the SHJ solar cell could be achieved by the wafer with a thickness of 100 μm. Fortunately, over 23% of the conversion efficiency of the SHJ solar cell with a wafer thickness of 100 μm was obtained based on the systematic optimization of cell fabrication process in the pilot production line. Evidently, the large availability of both n-type ingot and thinner wafer strongly supported the lower cost fabrication of high efficiency SHJ solar cell.
基金supported by Gazi University Scientific Research Project (BAP),FEF. 05/2012-15
文摘In this paper, the electrical parameters of Au/n-Si （MS） and Au/Si3N4/n-Si （MIS） Schottky diodes are obtained from the forward bias current-voltage （I-V） and capacitance-voltage （C-V） measurements at room temperature. Experimental results show that the rectifying ratios of the MS and MIS diodes at ± 5 V are found to be 1.25 ×103 and 1.27 ×104, respectively. The main electrical parameters of the MS and MIS diodes, such as the zero-bias barrier height （rbBo） and ideality factor （n）, are calculated to be 0.51 eV （I-V）, 0.53 eV （C-V）, and 4.43, and 0.65 eV （I-V）, 0.70 eV （C-V）, and 3.44, respectively. In addition, the energy density distribution profile of the interface states （Nss） is obtained from the forward bias I-V, and the series resistance （Rs） values for the two diodes are calculated from Cheung＇s method and Ohm＇s law.
基金supported by the Basic Science Center Program for Ordered Energy Conversion of the National Natural Science Foundation of China(51888103)Shaohua Shen is grateful to the National Natural Science Foundation of China(52225606)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Youth Innovation Team of Shaanxi Universities。
文摘n型硅(n-Si)表面在水溶液中容易被氧化和钝化,导致其在光电化学(PEC)分解水的析氧反应(OER)动力学缓慢。本工作通过欠电位沉积成功地在p^(+)n-Si基底上电沉积了三金属Ni_(0.9)Fe_(0.05)Co_(0.05)保护层。制备的Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极具有优异的稳定性和PEC水氧化活性,具有相对低的OER起始电位(相对于可逆氢电极电势(RHE)仅为0.938 V),并且在1.23 V vs.RHE电位时具有较高的光电流密度(33.1 m A·cm^(-2)),显著优于Ni/p^(+)n-Si光阳极。工作证明了Fe在Ni层的掺杂会在Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si界面处产生较大的能带弯曲,促进界面电荷分离。此外,Co的加入会产生丰富的Ni^(3+)和氧空位(Ov),作为活性位点可以加速OER动力学过程,协同促进PEC过程中的水氧化的活性。令人鼓舞的是,通过将Ni_(0.9)Fe_(0.05)Co_(0.05)/p^(+)n-Si光阳极连接到廉价的硅太阳能电池上,所制备的集成光伏/PEC(PV/PEC)器件实现了无偏压下高达12.0%的太阳制氢能量转换效率。这项工作提供了一种简单的方法来设计高效、稳定的n-Si基光阳极,并对其构效关系有了深刻的理解;这种方法制备的材料在集成低成本PV/PEC器件用于无辅助太阳能驱动水分解方面具有巨大的潜力。
