期刊
ACS NANO
卷 15, 期 1, 页码 1805-1816出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsnano.0c09584
关键词
strain-induced metallic states; zipper-like interdigitated atomically thin interfaces; efficient charge extraction; high efficiency; halide perovskite solar cells
类别
资金
- Global Frontier R&D Center for Hybrid Interface Materials [2013M3A6B1078884]
- National Research Foundation of Korea [2017R1A2B3009872, 202019M3E6A1104196, 2020R1A4A2002806, 2020H1D3A2A02104083]
- KISTI Supercomputing Center [KSC-2018-CHA-0032]
This study successfully created a zipper-like interdigitated interface between a Pb-based halide perovskite light absorber and an oxide ETL, significantly enhancing the charge extraction process. Experimental and computational evidence identified the atomistic origin of the emergent two-dimensional interfacial metallicity. The unconventional defect-passivating nature of the strained interdigitated perovskite/ETL interface was emphasized, leading to improved charge extraction efficiency and higher photovoltaic performance.
Halide perovskite light absorbers have great advantages for photovoltaics such as efficient solar energy absorption, but charge accumulation and recombination at the interface with an electron transport layer (ETL) remain major challenges in realizing the absorbers' full potential. Here we report the experimental realization of a zipper-like interdigitated interface between a Pb-based halide perovskite light absorber and an oxide ETL by the PbO capping of the ETL surface, which produces an atomically thin two-dimensional metallic layer that can significantly enhance the perovskite/ETL charge extraction process. As the atomistic origin of the emergent two-dimensional interfacial metallicity, first-principles calculations performed on the representative MAPbI(3)/TiO2 interface identify the interfacial strain induced by the simultaneous formation of stretched I-substitutional Pb bonds (and thus Pb-I-Pb bonds bridging MAPbI(3) and TiO2) and contracted substitutional Pb-O bonds. Direct and indirect experimental evidence for the presence of interfacial metallic states are provided, and a nonconventional defect-passivating nature of the strained interdigitated perovskite/ETL interface is emphasized. It is experimentally demonstrated that the PbO capping method is generally applicable to other ETL materials, including ZnO and SrTiO3, and that the zipper-like interdigitated metallic interface leads to about a 2-fold increase in the charge extraction rate. Finally, in terms of the photovoltaic efficiency, we observe a volcano-type behavior with the highest performance achieved at the monolayer-level PbO capping. This work establishes a general perovskite/ETL interface engineering approach to realize high-performance perovskite solar cells.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据