B-modified phosphorene for N2 fixation: A highly efficient metal-free photocatalyst

Highlights: • A novel B modified phosphorene-based non-metal photocatalyst. • B atom acts as charge transmitter to provide electron to N₂ and makes N₂ activate. • The lower onset potential of 0.34 V for B/AC-posphorene. • Excellent photoelectronic properties contribute to high catalytic efficiency. The chemically inert N₂ molecular can be converted into NH₃ through the Haber–Bosch process at the expense of energy source and pollution. Exploring an efficient photocatalyst for N₂ fixation is of great significance. Here, we theoretically designed a kind of B-modified phosphorene photocatalyst to achieve N₂ fixation based on the first-principle calculations. The N₂ molecules can be efficiently reduced into NH₃ on the B/AC-phosphorene with the lower onset potential of 0.34 V, which makes the energy barrier reduce by 150% compared with the related previous report. Moreover, the N₂ fixation mechanisms of B-modified phosphorene were explored. The B atom can act as transmitter to provide electron to N₂ and make it activate. Meanwhile, the extension of light absorption spectrum, the increase of adsorption coefficient in the VIS and IR and the decrease of bandgap can make the phosphorene utilize sunlight efficiently to achieve N₂ reduction. This study provides a novel way at the atomic level to explore highly efficient and environmentally friendly phosphorene based non-metal photocatalysts for N₂ fixation in the experiments.