摘要
Due to the better stability and environmentfriendly nature,lead-free halide double perovskites are widely explored as promising materials for next-generation photovoltaics and optoelectronics;however,to date,their photoelectric device performance is still not satisfactory.Herein,we report a facile solution-process method to synthesize the recently most popular lead-free halide double perovskite,MA_(2)Ag Bi Br_(6),and its all-inorganic counterpart,Cs_(2)Ag Bi Br_(6).The obtained MA_(2)Ag Bi Br_(6)and Cs_(2)Ag Bi Br_(6)films exhibit the microplatelet morphology with excellent crystallinity,distinctly contrasting the ones fabricated by the conventional spin-coating method.Once fabricated into simple photodetectors,the Cs_(2)Ag Bi Br_(6)microplatelet devices yield a respectable responsivity of 245 m A W^(-1) that is two orders of magnitude larger than that of the spin-coated films.More importantly,the response speed of the Cs_(2)Ag Bi Br_(6)microplatelets device is as fast as 145μs,which is higher than most of the values reported in the community of halide double perovskites.When subjected to the thermal stability testing,the Cs_(2)Ag Bi Br_(6)microplatelet device can maintain its initial performance after heating to 160℃ and cooling down to room temperature in the ambient environment.All these results suggest that the facile solution-process method is capable of fabricating high-quality lead-free double perovskites,enabling their advanced device applications.
无铅双钙钛矿由于具有较好的稳定性和无毒的特点吸引了很多学者的目光,有希望成为下一代光伏和光电子材料.然而,目前其光电器件性能并不理想.我们报道了一个简单的溶液法用于制备无机双钙钛矿Cs_(2)AgBiBr_(6)和MA_(2)AgBiBr_(6)微米片.与传统的溶液旋涂法相比,这种方法得到的Cs_(2)AgBiBr_(6)和MA_(2)Ag Bi Br_(6)微米片具有很好的结晶性.将它们做成光电探测器后,其响应度达到了245 mA W^(-1),比旋涂法制备的器件高出两个量级,且响应时间为145μs.热稳定性研究表明,将Cs_(2)AgBiBr_(6)器件在空气中加热到160℃再回到室温,其光电响应并没有受到影响.这些结果表明,溶液法制备无铅双钙钛矿具有更广阔的应用前景.
作者
Zhengxun Lai
Fei Wang
You Meng
Xiuming Bu
Xiaolin Kang
Quan Quan
Wei Wang
SenPo Yip
Chuntai Liu
Johnny C.Ho
赖征勋;王飞;孟优;卜修明;康小林;全泉;王巍;叶晨宝;刘春太;何颂贤(Department of Materials Science and Engineering,City University of Hong Kong,Kowloon 999077,Hong Kong SAR,China;State Key Laboratory of Luminescence and Applications,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130021,China;State Key Laboratory of Terahertz and Millimeter Waves,City University of Hong Kong,Kowloon 999077,Hong Kong SAR,China;Institute for Materials Chemistry and Engineering,Kyushu University,Fukuoka 816-8580,Japan;Key Laboratory of Advanced Materials Processing&Mold(Ministry of Education),Zhengzhou University,Zhengzhou 450002,China)
基金
financially supported by the Research Fellow Scheme(RFS2021-1S04)
the Theme-based Research(T42-103/16-N)of the Research Grants Council of Hong Kong SAR,China
Foshan Innovative and Entrepreneurial Research Team Program(2018IT100031)。
