标题：Tellurium-Based Double Perovskites A2TeX6 with Tunable Band Gap and Long Carrier Diffusion Length for Optoelectronic Applications
作者：Ju D.; Zheng X.; Yin J.; Qiu Z.; Türedi B.; Liu X.; Dang Y.; Cao B.;等 更多 作者机构：[Ju, D] State Key Laboratory of Crystal Materials, Institute of Crystal Materials, Shandong University, No. 27 Shanda South Road, Jinan, 250100, China 更多
通讯作者地址：[Cao, B] Materials Research Center for Energy and Photoelectrochemical Conversion, School of Material Science and Engineering, University of JinanChin 更多
来源：ACS Energy Letters
摘要：Lead-free hybrid perovskites have attracted immense interest as environmentally friendly light absorbers. Here, we report on tellurium (Te)-based double perovskites A2TeX6 (A = MA, FA, or BA; X = Br- or I- MA = CH3NH3; FA = CH(NH2)2; BA = benzylamine) as potentially active materials for optoelectronic devices. These perovskites exhibit a tunable band gap (1.42-2.02 eV), a low trap density (∼1010 cm-3), and a high mobility (∼65 cm2 V-1 s-1). Encouragingly, the MA2TeBr6 single crystal with a band gap of 2.00 eV possesses a long carrier lifetime of ∼6 μs and corresponding carrier diffusion lengths of ∼38 μm, which are ideal characteristics for a material for photodetectors and tandem solar cells. Moreover, A2TeX6 perovskites are relatively robust in ambient conditions, being stable for at least two months without showing any signs of phase change. Our findings bring to the forefront a family of lead-free Te-based perovskites for nontoxic perovskite optoelectronics. © Copyright 2018 American Chemical Society.