Planar Heterojunction Perovskite Solar Cells via Vapor-Assisted Solution Process

TLDR

Hybrid organic/inorganic perovskites such as CH3NH3PbI3 are promising light absorbers for third‑generation photovoltaics. The study demonstrates a low‑temperature vapor‑assisted solution process to produce polycrystalline perovskite thin films with full surface coverage, low roughness, and microscale grains. The process relies on vapor‑assisted solution deposition, and the authors discuss the kinetic and thermodynamic parameters governing perovskite film growth. The resulting solar cells achieve a 12.1 % power‑conversion efficiency, the highest reported for CH3NH3PbI3 planar heterojunctions, and the method offers a simple, reproducible route to high‑performance devices.

Abstract

Hybrid organic/inorganic perovskites (e.g., CH3NH3PbI3) as light absorbers are promising players in the field of third-generation photovoltaics. Here we demonstrate a low-temperature vapor-assisted solution process to construct polycrystalline perovskite thin films with full surface coverage, small surface roughness, and grain size up to microscale. Solar cells based on the as-prepared films achieve high power conversion efficiency of 12.1%, so far the highest efficiency based on CH3NH3PbI3 with the planar heterojunction configuration. This method provides a simple approach to perovskite film preparation and paves the way for high reproducibility of films and devices. The underlying kinetic and thermodynamic parameters regarding the perovskite film growth are discussed as well.