Vacuum-filtration enabled large-area CsPbBr3 films on porous substrates for flexible photodetectors. Issue 43 (25th October 2019)

• Record Type: Journal Article
• Authors: Tan, Qishuo; Ye, Guo; Zhang, Yan; Du, Xiaojia; Liu, Haining; Xie, Liming; Zhou, Yu; Liu, Nan
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 43(2019)
• Page Start: 13402
• Page End: 13409
• Publication Date: 2019-10-25
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9tc04032c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Here, we report a vacuum-filtration method to produce centimeter-scale continuous polycrystalline inorganic perovskite (CsPbBr3 ) film directly on flexible porous substrates in one step, and demonstrate large-area flexible photodetector arrays. Abstract : All-inorganic perovskites (CsPbX3, X = Br, Cl, I) have been considered as promising candidates for developing high-performance, flexible and lightweight optoelectronic devices due to their high absorption coefficient, mechanical durability, low-temperature synthesis ability and stable physiochemical properties. However, the fabrication of pinhole-free, large-scale inorganic perovskite films is still a great challenge, because it is limited by strong chemical bonds and really low solubility, impeding their application in flexible solar cells, photodetectors and light emitting diodes. In this paper, a vacuum-filtration method to deposit large-scale, compact all-inorganic perovskite films from nanosheet suspensions on arbitrary porous substrates, which allows control of the uniformity and thickness of the perovskite films, is reported. The performance of the fabricated flexible-photodetectors was greatly improved by adding a proper amount of carbon nanotube (CNT) additive, which could maintain the low dark current density and increase the photo-responsivity by suppressing the photocarrier recombination. The improved photodetectors showed a large on/off ratio of >1 × 10 4, and a fast rise/decay time of 52/14 ms. These flexible photodetectors demonstrated excellent mechanical bending capabilities with retained performance after 1000 bending cycles. This deposition method could provide a universal route for preparing inorganic material films for fundamental studies and practical applications.