Lead-free double perovskite,Cs2AgBiBr6,with higher stability and lower toxicity than those of its lead counterparts,has been considered a promising alternative for next-generation photovoltaic materials.For practical ...Lead-free double perovskite,Cs2AgBiBr6,with higher stability and lower toxicity than those of its lead counterparts,has been considered a promising alternative for next-generation photovoltaic materials.For practical applications,a facile deposition method that could be used to fabricate high-quality double perovskite films with large grain size is highly desired.However,such kind of facile method has never been established for Cs2AgBiBr6.Herein,high-quality Cs2AgBiBr6thin films with an average grain size of approximately 0.5μm were successfully deposited via a simple onestep spin-coating method by using dimethyl sulfoxide(DMSO)-N,N-dimethylformamide(DMF)mixture with optimized volume ratio as the solvent and chlorobenzene(CB)as the antisolvent.On the basis of satisfactory quality of the film efficient(>1%)Cs2AgBiBr6perovskite solar cells were constructed.Furthermore,the photo-generated charge-carrier transfer from Cs2AgBiBr6to the adjacent carrier extraction layers was systematically investigated via femtosecond transient spectroscopies.This study offers a new pathway to acquiring high-quality Cs2AgBiBr6thin films and provides a useful guide toward the development of high-efficiency double perovskite solar cells in the future.展开更多
By theoretical analysis of heat transfer during the "one-step" directional solidification process, the functional relation between the temperature in solid-liquid interface and its effect factor was studied....By theoretical analysis of heat transfer during the "one-step" directional solidification process, the functional relation between the temperature in solid-liquid interface and its effect factor was studied. The thermal gradient in solid liquid interface and heat transfer coefficient between the samples and surroundings were also calculated. On the basis of the above analysis, some suggestions for improving the thermal gradient in solid-liquid interface were put forward. It will provide a theoretical instruction for preparing high performance giant magnetostrictive materials (GMM).展开更多
基金financial support from Macao Science and Technology Development Fund(FDCT-116/2016/A3,FDCT-091/2017/A2 and FDCT-014/2017/AMJ)the Research Grants(SRG2016-00087-FST,MYRG2018-00148-IAPME)from University of Macao+1 种基金the National Natural Science Foundation of China(91733302,61605073,61935017)the Natural Science Foundation of Guangdong Province,China(2019A1515012186)。
文摘Lead-free double perovskite,Cs2AgBiBr6,with higher stability and lower toxicity than those of its lead counterparts,has been considered a promising alternative for next-generation photovoltaic materials.For practical applications,a facile deposition method that could be used to fabricate high-quality double perovskite films with large grain size is highly desired.However,such kind of facile method has never been established for Cs2AgBiBr6.Herein,high-quality Cs2AgBiBr6thin films with an average grain size of approximately 0.5μm were successfully deposited via a simple onestep spin-coating method by using dimethyl sulfoxide(DMSO)-N,N-dimethylformamide(DMF)mixture with optimized volume ratio as the solvent and chlorobenzene(CB)as the antisolvent.On the basis of satisfactory quality of the film efficient(>1%)Cs2AgBiBr6perovskite solar cells were constructed.Furthermore,the photo-generated charge-carrier transfer from Cs2AgBiBr6to the adjacent carrier extraction layers was systematically investigated via femtosecond transient spectroscopies.This study offers a new pathway to acquiring high-quality Cs2AgBiBr6thin films and provides a useful guide toward the development of high-efficiency double perovskite solar cells in the future.
基金This project was supported by the Natural Science Foundation of Beijing (2042012)
文摘By theoretical analysis of heat transfer during the "one-step" directional solidification process, the functional relation between the temperature in solid-liquid interface and its effect factor was studied. The thermal gradient in solid liquid interface and heat transfer coefficient between the samples and surroundings were also calculated. On the basis of the above analysis, some suggestions for improving the thermal gradient in solid-liquid interface were put forward. It will provide a theoretical instruction for preparing high performance giant magnetostrictive materials (GMM).
