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.