Contact Engineering of Halide Perovskites: Gold is Not Good Enough; Metalloid is Better

The operation stability of halide perovskite devices is the critical issue that impedes their commercialization. The main reasons are that the ambient H2O molecules can easily deteriorate the perovskites, while the metal electrodes react in different degrees with the perovskites. Herein, one kind of new electrode, the metalloids, is reported, which are much more stable than the conventional noble metals as electrical contacts for halide perovskites. The degradation mechanism of halide perovskites with noble metal electrodes is carefully studied and compared with the metalloid electrodes. It is found that the iodide ions can easily halogenate Cu and Ag in halide perovskites. Although Au is almost not halogenated, it can also decompose the perovskite film. On the contrary, after long-term storage, the metalloid electrodes remain intact on the perovskite film without any degradation. In addition, the long-time operation stability of the perovskite devices with metalloid electrodes is much higher than that of noble metals. First-principles calculations confirm the exceptional stability of the metalloid electrodes.This work explores the ultra-stable electrodes for halide perovskites, paving the way to the large-scale deployment of perovskite-based electronic devices.

Automated summary

This study reports a new type of electrode, metalloid electrode, which is more stable than conventional noble metals as electrical contacts for halide perovskites. The degradation mechanism of noble metal electrodes compared to metalloid electrodes is investigated, and it is found that noble metals are prone to halogenation in halide perovskites, while metalloid electrodes remain intact after long-term storage. Furthermore, the long-time operation stability of perovskite devices with metalloid electrodes is higher than that of noble metals. First-principles calculations confirm the exceptional stability of metalloid electrodes.