Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:...Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:Sb,S,and Se.However,this process generates an unfavourable gradient of Se and S anions in the Sb_(2)(S,Se)_(3)film,which limits further efficiency improvements.Herein,we demonstrate how NH_(4)F can be used as an additive to regulate the band gradient of the Sb_(2)(S,Se)_(3)and modify the surface of the CdS electron-transporting layer.On the one hand,NH_(4)F inhibits the decomposition of Na_(2)S_(2)O_(3)and selenourea,which optimizes the deposition process and allows for adjustment of the Se/S ratio and their distribution in the Sb_(2)(S,Se)_(3)film.On the other hand,hydrolysis of NH_(4)F induces dissolution and redeposition of CdS,thereby effectively improving the morphology and crystallinity of the CdS substrate.Finally,the dual effect of NH_(4)F enables improved surface morphology and energy alignment of the Sb_(2)(S,Se)_(3)film,thus yielding a maximum efficiency of 10.28%,a 12%improvement over the control device.This study demonstrates an effective strategy for simultaneously modifying a sulfide-based substrate and regulating the element distribution during the deposition of a metal chalcogenide film for optoelectronic device applications.展开更多
Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications....Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications. The n–n type heterojunction was formed by hydrothermal deposition of Sb_(2)(S,Se)_(3) and thermal evaporation of Sb_(2)Se_(3). We found that the n–n junction is able to enhance the carrier separation by the formation of an electric field, reduce the interfacial recombination and generate optimized band alignment. The device based on this n–n junction shows 2.89% net efficiency improvement to 7.75%when compared with the device consisted of semiconductor absorber–metal contact. The study in the n–n type solar cell is expected to bring about more versatile materials utility, new interfacial engineering strategy and fundamental findings in the photovoltaic energy conversion process.展开更多
基金the National Natural Science Foundation of China(22005293 and U19A2092)the National Key Research and Development Program of China(2019YFA0405600).
文摘Hydrothermal deposition of antimony selenosulfide(Sb_(2)(S,Se_(3)))has enabled solar cell applications to surpass the 10%efficiency threshold.This deposition process involves the reaction of three precursor materials:Sb,S,and Se.However,this process generates an unfavourable gradient of Se and S anions in the Sb_(2)(S,Se)_(3)film,which limits further efficiency improvements.Herein,we demonstrate how NH_(4)F can be used as an additive to regulate the band gradient of the Sb_(2)(S,Se)_(3)and modify the surface of the CdS electron-transporting layer.On the one hand,NH_(4)F inhibits the decomposition of Na_(2)S_(2)O_(3)and selenourea,which optimizes the deposition process and allows for adjustment of the Se/S ratio and their distribution in the Sb_(2)(S,Se)_(3)film.On the other hand,hydrolysis of NH_(4)F induces dissolution and redeposition of CdS,thereby effectively improving the morphology and crystallinity of the CdS substrate.Finally,the dual effect of NH_(4)F enables improved surface morphology and energy alignment of the Sb_(2)(S,Se)_(3)film,thus yielding a maximum efficiency of 10.28%,a 12%improvement over the control device.This study demonstrates an effective strategy for simultaneously modifying a sulfide-based substrate and regulating the element distribution during the deposition of a metal chalcogenide film for optoelectronic device applications.
基金Project supported by Institute of Energy, Hefei Comprehensive National Science Center (Grant No. 21KZS212)the National Key Research and Development Program of China (Grant No. 2019YFA0405600)+2 种基金the National Natural Science Foundation of China (Grant Nos. U19A2092 and 22005293)the China Postdoctoral Science Foundation (Grant No. 2021M693045)Collaborative Innovation Program of Hefei Science Center, Chinese Academy of Sciences。
文摘Carrier separation in a solar cell usually relies on the p–n junction. Here we show that an n–n type inorganic semiconductor heterojunction is also able to separate the exciton for efficient solar cell applications. The n–n type heterojunction was formed by hydrothermal deposition of Sb_(2)(S,Se)_(3) and thermal evaporation of Sb_(2)Se_(3). We found that the n–n junction is able to enhance the carrier separation by the formation of an electric field, reduce the interfacial recombination and generate optimized band alignment. The device based on this n–n junction shows 2.89% net efficiency improvement to 7.75%when compared with the device consisted of semiconductor absorber–metal contact. The study in the n–n type solar cell is expected to bring about more versatile materials utility, new interfacial engineering strategy and fundamental findings in the photovoltaic energy conversion process.
