A vacuum flash–assisted solution process for high-efficiency large-area perovskite solar cells

TLDR

Metal halide perovskite solar cells promise high efficiency and low cost, yet scaling to large devices remains challenging. The authors aim to devise a vacuum flash–assisted solution process that yields high‑quality perovskite films across large areas. The process employs vacuum flash–assisted deposition to produce shiny, smooth, crystalline films with superior electronic properties. Using this method, the authors fabricated >1 cm² cells achieving 20.5 % efficiency (certified 19.6 %), surpassing the previous 15.6 % benchmark, with excellent reproducibility and negligible hysteresis, demonstrating the viability of large‑area high‑efficiency PSCs.

Abstract

Metal halide perovskite solar cells (PSCs) currently attract enormous research interest because of their high solar-to-electric power conversion efficiency (PCE) and low fabrication costs, but their practical development is hampered by difficulties in achieving high performance with large-size devices. We devised a simple vacuum flash–assisted solution processing method to obtain shiny, smooth, crystalline perovskite films of high electronic quality over large areas. This enabled us to fabricate solar cells with an aperture area exceeding 1 square centimeter, a maximum efficiency of 20.5%, and a certified PCE of 19.6%. By contrast, the best certified PCE to date is 15.6% for PSCs of similar size. We demonstrate that the reproducibility of the method is excellent and that the cells show virtually no hysteresis. Our approach enables the realization of highly efficient large-area PSCs for practical deployment.