Metal-Encapsulated Boron Nitride Nanocages for Solar-Driven Nitrogen Fixation

Boron nitride (BN) nanostructures with excellent thermal and chemical stabilities hold great promise for many industrial applications. However, activation of the inert BN surface for various catalytic reactions remains a grand challenge. Herein, we exploit a series of metal-encapsulated BN nanocages M 4 @B 36 N 36 (M is an early or a middle transition metal atom), which are feasible in the experiment, for catalysis of N 2 reduction reaction (NRR). Our first-principles calculations show that these core–shell BN nanoclusters are robust and exhibit outstanding stability in an aqueous environment. They have strong capability for activating N 2 molecules and broad spectra of optical absorption for solar-driven NRR with ultralow onset potential. The mechanism of the synergistic effect between the metal filler and BN cages as well as the regulation for precisely controlling the activity by manipulating the occupancy of B p states are clearly revealed. These theoretical results provide essential physical insights for utilizing the stable and inexpensive BN nanomaterials for solar energy conversion and ammonia economy.