High-efficiency perovskite solar cells（PSCs） reported hitherto have been mostly prepared in a moisture and oxygen-free glove-box atmosphere, which hampers upscaling and real-time performance assessment of this excit...High-efficiency perovskite solar cells（PSCs） reported hitherto have been mostly prepared in a moisture and oxygen-free glove-box atmosphere, which hampers upscaling and real-time performance assessment of this exciting photovoltaic technology. In this work, we have systematically studied the feasibility of allambient-processing of PSCs and evaluated their photovoltaic performance. It has been shown that phasepure crystalline tetragonal MAPbI;perovskite films are instantly formed in ambient air at room temperature by a two-step spin coating process, undermining the need for dry atmosphere and post-annealing.All-ambient-processed PSCs with a configuration of FTO/TiO;/MAPbI;/Spiro-OMeTAD/Au achieve opencircuit voltage（990 mV） and short-circuit current density（20.31 mA/cm;） comparable to those of best reported glove-box processed devices. Nevertheless, device power conversion efficiency is still constrained at 5% by the unusually low fill-factor of 0.25. Dark current–voltage characteristics reveal poor conductivity of hole-transporting layer caused by lack of oxidized spiro-OMe TAD species, resulting in high seriesresistance and decreased fill-factor. The study also establishes that the above limitations can be readily overcome by employing an inorganic p-type semiconductor, copper thiocyanate, as ambient-processable hole-transporting layer to yield a fill-factor of 0.54 and a power conversion efficiency of 7.19%. The present findings can have important implications in industrially viable fabrication of large-area PSCs.展开更多
Numerous fabrication methods have been developed for high-efficiency perovskite solar cells(PSCs). However, these are limited to spin-coating processes in a glove box and are yet to be commercialized. Therefore, there...Numerous fabrication methods have been developed for high-efficiency perovskite solar cells(PSCs). However, these are limited to spin-coating processes in a glove box and are yet to be commercialized. Therefore, there is a need to develop a controllable and scalable deposition technique that can be carried out under ambient conditions. Even though the doctor-blade coating technique has been widely used to prepare PSCs, it is yet to be applied to high-efficiency PSCs under ambient conditions(RH ~45%, RT ~25 °C). In this study, we conducted blade-coating fabrication of modified high-efficiency PSCs under such conditions. We controlled the substrate temperature to ensure phase transition of perovskite and added dimethyl sulfoxide(DMSO) to the perovskite precursor solution to delay crystallization, which can facilitate the formation of uniform perovskite films by doctor-blade coating. The as-prepared perovskite films had large crystal domains measuring up to 100 μm. Solar cells prepared from these films exhibited a current density that was enhanced from 17.22 to 19.98 m A/cm^2 and an efficiency that was increased from 10.98% to 13.83%. However, the open-circuit voltage was only 0.908 V, probably due to issues with the hole-transporting layer. Subsequently, we replaced poly(3,4-ethylenedioxythiophene) polystyrene sulfonate(PEDOT:PSS) with Ni O x as the hole-transporting material and then prepared higher-quality perovskite films by blade-coating under ambient conditions. The as-prepared perovskite films were preferably orientated and had large crystal domains measuring up to 200 μm;The open-circuit voltage of the resulting PSCs was enhanced from 0.908 to 1.123 V, while the efficiency increased from 13.83% to 15.34%.展开更多
基于无机CsPbI_(2)Br的碳基无空穴传输层钙钛矿太阳能电池(carbon based hole transport material freeperovskite solar cells,C-PSCs)具有成本低、易制备和稳定性好等优点而受到广泛关注。研究了空气环境下制备高效稳定的平面异质结Cs...基于无机CsPbI_(2)Br的碳基无空穴传输层钙钛矿太阳能电池(carbon based hole transport material freeperovskite solar cells,C-PSCs)具有成本低、易制备和稳定性好等优点而受到广泛关注。研究了空气环境下制备高效稳定的平面异质结CsPbI_(2)Br C-PSCs的2种制备工艺。首先,通过对反溶剂材料的种类及用量、钙钛矿前驱体溶液浓度等参数的优化,在反溶剂为800μL、钙钛矿前驱体溶液浓度为1.2 mol/L的条件下,采用一步溶液法成功制备了光电转换效率为9.87%的CsPbI_(2)Br C-PSCs。其次,为摆脱一步溶液法对有毒反溶剂的依赖,引入低温预退火工艺,通过对预退火时间及温度、钙钛矿前驱体溶液浓度等参数的优化,在空气环境下,预退火温度为80℃、钙钛矿前驱体溶液浓度为1.6 mol/L且未使用反溶剂的条件下获得了10.52%的最佳光电转化效率,同时CsPbI_(2)Br钙钛矿的退火温度可降低至240℃,并且未封装的器件在空气环境下显示出了较好的稳定性。展开更多
文摘High-efficiency perovskite solar cells（PSCs） reported hitherto have been mostly prepared in a moisture and oxygen-free glove-box atmosphere, which hampers upscaling and real-time performance assessment of this exciting photovoltaic technology. In this work, we have systematically studied the feasibility of allambient-processing of PSCs and evaluated their photovoltaic performance. It has been shown that phasepure crystalline tetragonal MAPbI;perovskite films are instantly formed in ambient air at room temperature by a two-step spin coating process, undermining the need for dry atmosphere and post-annealing.All-ambient-processed PSCs with a configuration of FTO/TiO;/MAPbI;/Spiro-OMeTAD/Au achieve opencircuit voltage（990 mV） and short-circuit current density（20.31 mA/cm;） comparable to those of best reported glove-box processed devices. Nevertheless, device power conversion efficiency is still constrained at 5% by the unusually low fill-factor of 0.25. Dark current–voltage characteristics reveal poor conductivity of hole-transporting layer caused by lack of oxidized spiro-OMe TAD species, resulting in high seriesresistance and decreased fill-factor. The study also establishes that the above limitations can be readily overcome by employing an inorganic p-type semiconductor, copper thiocyanate, as ambient-processable hole-transporting layer to yield a fill-factor of 0.54 and a power conversion efficiency of 7.19%. The present findings can have important implications in industrially viable fabrication of large-area PSCs.
基金supported by the National Key Research and Development Project funding from the Ministry of Science and Technology of China (Grants Nos. 2016YFA0202400 and 2016YFA0202404)the Peacock Team Project funding from Shenzhen Science and Technology Innovation Committee (Grant No. KQTD2015033110182370)+1 种基金the Fundamental Research (Discipline Arrangement) Project funding from Shenzhen Science and Technology Innovation Committee (Grant No. JCYJ20170412154554048)the National Natural Science Foundation of China (Grant No. 51473139)
文摘Numerous fabrication methods have been developed for high-efficiency perovskite solar cells(PSCs). However, these are limited to spin-coating processes in a glove box and are yet to be commercialized. Therefore, there is a need to develop a controllable and scalable deposition technique that can be carried out under ambient conditions. Even though the doctor-blade coating technique has been widely used to prepare PSCs, it is yet to be applied to high-efficiency PSCs under ambient conditions(RH ~45%, RT ~25 °C). In this study, we conducted blade-coating fabrication of modified high-efficiency PSCs under such conditions. We controlled the substrate temperature to ensure phase transition of perovskite and added dimethyl sulfoxide(DMSO) to the perovskite precursor solution to delay crystallization, which can facilitate the formation of uniform perovskite films by doctor-blade coating. The as-prepared perovskite films had large crystal domains measuring up to 100 μm. Solar cells prepared from these films exhibited a current density that was enhanced from 17.22 to 19.98 m A/cm^2 and an efficiency that was increased from 10.98% to 13.83%. However, the open-circuit voltage was only 0.908 V, probably due to issues with the hole-transporting layer. Subsequently, we replaced poly(3,4-ethylenedioxythiophene) polystyrene sulfonate(PEDOT:PSS) with Ni O x as the hole-transporting material and then prepared higher-quality perovskite films by blade-coating under ambient conditions. The as-prepared perovskite films were preferably orientated and had large crystal domains measuring up to 200 μm;The open-circuit voltage of the resulting PSCs was enhanced from 0.908 to 1.123 V, while the efficiency increased from 13.83% to 15.34%.
文摘基于无机CsPbI_(2)Br的碳基无空穴传输层钙钛矿太阳能电池(carbon based hole transport material freeperovskite solar cells,C-PSCs)具有成本低、易制备和稳定性好等优点而受到广泛关注。研究了空气环境下制备高效稳定的平面异质结CsPbI_(2)Br C-PSCs的2种制备工艺。首先,通过对反溶剂材料的种类及用量、钙钛矿前驱体溶液浓度等参数的优化,在反溶剂为800μL、钙钛矿前驱体溶液浓度为1.2 mol/L的条件下,采用一步溶液法成功制备了光电转换效率为9.87%的CsPbI_(2)Br C-PSCs。其次,为摆脱一步溶液法对有毒反溶剂的依赖,引入低温预退火工艺,通过对预退火时间及温度、钙钛矿前驱体溶液浓度等参数的优化,在空气环境下,预退火温度为80℃、钙钛矿前驱体溶液浓度为1.6 mol/L且未使用反溶剂的条件下获得了10.52%的最佳光电转化效率,同时CsPbI_(2)Br钙钛矿的退火温度可降低至240℃,并且未封装的器件在空气环境下显示出了较好的稳定性。
