Edge-Rich Black Phosphorus for Photocatalytic Nitrogen Fixation

Development of efficient catalysts for ammonia production under ambient conditions is a challenge. In this work, edge-rich black phosphorus nanoflakes (eBP NFs) are synthesized for highly efficient photocatalytic nitrogen fixation. The eBP NFs synthesized by a chemical etching exfoliation method have a uniform size and about 90 nm wide and the flake-like structure is enshrouded with crystal-domain edges. Without using any cocatalysts, the eBP NFs catalyze nitrogen fixation at a rate of 2.37 mmol·h^-1·g^-1 under visible-light irradiation. The photocatalytic process is analyzed by photoelectrochemical and transient absorption measurements, which disclose electron transfer from eBP NFs to N₂ for subsequent hydrogenation. Besides the facile and scalable synthesis method, eBP NFs with a high photocatalytic nitrogen fixation efficiency have great potential in ammonia production.