Direct gas phase synthesis of high-purity black arsenic phosphorus with non-metallic mineralizer

Abstract

2D black arsenic phosphorus (b-AsP) is a promising candidate for infrared photodetectors. However, directly synthesizing high-purity b-AsP crystals under the existing system is an intractable task. Herein, we report a novel system for synthesizing high-purity b-AsP crystals using non-metallic mineralizer. A small amount of I2 was chosen as the sole additive for the synthesis of b-AsP to avoid metal by-products, and impurities were removed through the reverse heating program after the reaction. Through optimization of process conditions, the efficient conversion rate of b-AsP was> 99%, and the purity of b-AsP crystal was as high as> 99.9% with favorable crystal form, diameter of ∼5 mm, and typical polycrystalline characteristics. The entire synthesis process took only 15 h. This facile and green route for b-AsP crystals synthesis might be expected to replace the existing b-AsP synthesis system and provide theoretical guidance for breakthroughs in the synthesis reaction mechanism of b-AsP materials.