Oligomeric Silica-Wrapped Perovskites Enable Synchronous Defect Passivation and Grain Stabilization for Efficient and Stable Perovskite Photovoltaics

Authors

Yang Bai, University of Queensland, University of Nebraska-Lincoln
Yun Lin, University of North Carolina, University of Nebraska-Lincoln
Long Ren, University of WollongongFollow
Xiao-Lei Shi, University of Queensland
Ekaterina Strounina, University of Queensland
Yehao Deng, University of North Carolina,University of Nebraska-Lincoln
Qi Wang, University of North Carolina,University of Nebraska-Lincoln
Yanjun Fang, University of Nebraska-Lincoln
Xiaopeng Zheng, University of Nebraska-Lincoln
Yuze Lin, University of North Carolina,University of Nebraska-Lincoln
Zhi-Gang Chen, University of Southern Queensland, University of Queensland
Yi Du, University of WollongongFollow
Lianzhou Wang, University of QueenslandFollow
Jinsong Huang, University of North Carolina,University of Nebraska-Lincoln

RIS ID

136419

Publication Details

Bai, Y., Lin, Y., Ren, L., Shi, X., Strounina, E., Deng, Y., Wang, Q., Fang, Y., Zheng, X., Lin, Y., Chen, Z., Du, Y., Wang, L. & Huang, J. (2019). Oligomeric Silica-Wrapped Perovskites Enable Synchronous Defect Passivation and Grain Stabilization for Efficient and Stable Perovskite Photovoltaics. ACS Energy Letters, 4 1231-1240.

Abstract

The intrinsic instability of hybrid perovskite materials induced by defect states arises as one major challenge hampering the commercialization of perovskite solar cells (PSCs). Here, we report a facile strategy of wrapping perovskite grains within an oligomeric silica (OS) matrix in a core-shell geometry, which can synchronously passivate the defects at surfaces and grain boundaries and stabilize the grains at the nanoscale. We observe a significant reduction of trap density and elongation of carrier lifetime in OS-wrapped perovskites, which yields an increased efficiency of 21.5% for p-i-n structured PSCs with a decent open-circuit voltage of 1.15 V and a fill factor of 0.81. This all-around nanoscale grain wrapping leads to remarkable improvement of the operational stability of PSCs, sustaining 80% of the efficiency after "burn-in" under full sunlight with UV for more than 5200 h. Our findings provide a new pathway towards efficient and stable PSCs.