Porous CuFe for Plasmon-Assisted N-2 Photofixation

Developing low-cost Cu-based photocatalysts is a promising strategy to boost catalytic activity for nitrogen (N-2) photofixation, but it remains a challenge. Herein, we successfully applied porous CuFe to construct plasmon-assisted Cu-based photocatalysts in N-2 photofixation via plasmonic catalysis. Surface Fe atoms were regarded as the active sites to efficiently adsorb and activate N-2, while Cu frameworks generated hot electrons by surface plasmon resonance (SPR). Impressively, porous Cu96Fe4 attained an NH3 production rate of 342 mu mol.g(cat.)(-1).h(-1) in N-2 photofixation without any sacrificial agents. More importantly, porous Cu96Fe4 also displayed excellent stability by maintaining similar to 100% initial activity after 10 cycles. Further mechanistic studies revealed that the valence state and coordination numbers of Fe atoms in porous Cu96Fe4 increased during catalytic process, indicating the formation of a surface nitrogen-containing complex. In addition, the reaction barrier significantly decreased because of the efficient polarization of N-2 over Fe atoms.