Layered-Double-Hydroxide Nanosheets as Efficient Visible-Light-Driven Photocatalysts for Dinitrogen Fixation

Semiconductor photocatalysis attracts widespread interest in water splitting, CO2 reduction, and N-2 fixation. N-2 reduction to NH3 is essential to the chemical industry and to the Earth's nitrogen cycle. Industrially, NH3 is synthesized by the Haber-Bosch process under extreme conditions (400-500 degrees C, 200-250 bar), stimulating research into the development of sustainable technologies for NH3 production. Herein, this study demonstrates that ultrathin layered-double-hydroxide (LDH) photocatalysts, in particular CuCr-LDH nanosheets, possess remarkable photocatalytic activity for the photoreduction of N-2 to NH3 in water at 25 degrees C under visible-light irradiation. The excellent activity can be attributed to the severely distorted structure and compressive strain in the LDH nanosheets, which significantly enhances N-2 chemisorption and thereby promotes NH3 formation.