Perovskite superlattices with efficient carrier dynamics

Yusheng Lei; Yuheng Li; Chengchangfeng Lu; Qizhang Yan; Yilei Wu; Finn Babbe; Huaxin Gong; Song Zhang; Jiayun Zhou; Ruotao Wang; Ruiqi Zhang; Yimu Chen; Hsinhan Tsai; Yue Gu; Hongjie Hu; Yu-Hwa Lo; Wanyi Nie; Taeyoon Lee; Jian Luo; Kesong Yang; Kyung-In Jang; Sheng Xu

doi:10.1038/s41586-022-04961-1

Perovskite superlattices with efficient carrier dynamics

Nature. 2022 Aug;608(7922):317-323. doi: 10.1038/s41586-022-04961-1. Epub 2022 Aug 10.

Authors

Yusheng Lei^#^{1

2}, Yuheng Li^#¹, Chengchangfeng Lu³, Qizhang Yan¹, Yilei Wu², Finn Babbe⁴, Huaxin Gong², Song Zhang², Jiayun Zhou⁵, Ruotao Wang¹, Ruiqi Zhang¹, Yimu Chen¹, Hsinhan Tsai⁶, Yue Gu⁵, Hongjie Hu¹, Yu-Hwa Lo³, Wanyi Nie⁶, Taeyoon Lee^{7

8}, Jian Luo^{1

5}, Kesong Yang¹, Kyung-In Jang⁹, Sheng Xu^{10

11

12

13}

Affiliations

¹ Department of Nanoengineering, University of California, San Diego, La Jolla, CA, USA.
² Department of Chemical Engineering, Stanford University, Stanford, CA, USA.
³ Department of Electrical and Computer Engineering, University of California, San Diego, La Jolla, CA, USA.
⁴ Chemical Sciences Division, Liquid Sunlight Alliance, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
⁵ Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA, USA.
⁶ Los Alamos National Laboratory, Los Alamos, NM, USA.
⁷ School of Electrical and Electronic Engineering, Yonsei University, Seoul, Republic of Korea.
⁸ Department of Bio and Brain Engineering, Korea Institute of Science and Technology, Seoul, Republic of Korea.
⁹ Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea.
¹⁰ Department of Nanoengineering, University of California, San Diego, La Jolla, CA, USA. shengxu@ucsd.edu.
¹¹ Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA, USA. shengxu@ucsd.edu.
¹² Los Alamos National Laboratory, Los Alamos, NM, USA. shengxu@ucsd.edu.
¹³ Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA. shengxu@ucsd.edu.

^# Contributed equally.

PMID: 35948711
DOI: 10.1038/s41586-022-04961-1

Abstract

Compared with their three-dimensional (3D) counterparts, low-dimensional metal halide perovskites (2D and quasi-2D; B₂A_n-1M_nX_3n+1, such as B = R-NH₃⁺, A = HC(NH₂)₂⁺, Cs⁺; M = Pb²⁺, Sn²⁺; X = Cl^-, Br^-, I^-) with periodic inorganic-organic structures have shown promising stability and hysteresis-free electrical performance^1-6. However, their unique multiple-quantum-well structure limits the device efficiencies because of the grain boundaries and randomly oriented quantum wells in polycrystals⁷. In single crystals, the carrier transport through the thickness direction is hindered by the layered insulating organic spacers⁸. Furthermore, the strong quantum confinement from the organic spacers limits the generation and transport of free carriers^9,10. Also, lead-free metal halide perovskites have been developed but their device performance is limited by their low crystallinity and structural instability¹¹. Here we report a low-dimensional metal halide perovskite BA₂MA_n-1Sn_nI_3n+1 (BA, butylammonium; MA, methylammonium; n = 1, 3, 5) superlattice by chemical epitaxy. The inorganic slabs are aligned vertical to the substrate and interconnected in a criss-cross 2D network parallel to the substrate, leading to efficient carrier transport in three dimensions. A lattice-mismatched substrate compresses the organic spacers, which weakens the quantum confinement. The performance of a superlattice solar cell has been certified under the quasi-steady state, showing a stable 12.36% photoelectric conversion efficiency. Moreover, an intraband exciton relaxation process may have yielded an unusually high open-circuit voltage (V_OC).

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.