Related Experiment Video
Updated: Jan 17, 2026
Low Pressure Vapor-assisted Solution Process for Tunable Band Gap Pinhole-free Methylammonium Lead Halide Perovskite Films
Published on: September 8, 2017
Liquid Ga nanodroplet-templated heteroepitaxy of MAPbI3 for high-efficiency printable mesoscopic perovskite solar
Jianhong Zhao1, Tong Zhou2, Tianwei He3
1Institute for Ecological Research and Pollution Control of Plateau Lakes, School of Ecology and Environmental Science, Yunnan University, Kunming 650091, China; Yunnan Key Laboratory for Micro/Nano Materials & Technology, International Joint Research Center for Optoelectronic and Energy Materials, School of Materials and Energy, Yunnan University, Kunming 650091, China.
Abstract:
Precise control over microstructure and crystallinity of perovskite films is pivotal for achieving high-performance solar cells. However, realizing large-grained and preferentially oriented perovskite crystals remains particularly challenging in printable mesoscopic architectures. Herein, we present a liquid-metal-enabled heteroepitaxial strategy to regulate MAPbI3 crystallization on Ga2O3 surfaces derived from Ga nanodroplets. Structural modeling and atomic-resolution transmission electron microscope (TEM) analysis reveal an exceptional lattice match between the (110) planes of MAPbI3 and the exposed Ga2O3 facets, with an ultralow mismatch of merely 0.32%. This near-perfect lattice alignment drives the formation of orientation-controlled MAPbI3 crystals within the mesoporous scaffold. Moreover, the epitaxial interface establishes type-II band alignment that accelerates charge extraction while suppressing interfacial recombination. The resultant printable mesoscopic perovskite solar cells achieve a champion power conversion efficiency (PCE) of 20.2% (AM1.5G), representing a 16% enhancement over conventional non-epitaxial counterparts. Crucially, the devices demonstrate exceptional operational stability, retaining 97% of initial PCE after 3000 h of maximum power point tracking under harsh conditions (55 ± 5 °C, 85% RH).
