Oxygen vacancy and Z-scheme heterojunction cooperate to promote visible light nitrogen photofixation

Abstract

The combination of defect engineering and heterojunction design is a viable method to achieve high efficiency photocatalytic nitrogen fixation. Oxygen vacancy engineered Fe2O3/CeO2 Z-scheme heterojunction was synthesized by thermal treatment with Ce-MOFs as precursor. Fe2O3/CeO2 with 30 wt% Fe2O3 exhibited the highest NH3 yield of 162 μmol·g−1·h−1 in water, about 2.5 and 4 times that of CeO2 and Fe2O3, respectively. The enhanced photocatalytic nitrogen fixation performance could be attributed to the synergistic effect of the oxygen vacancies and the Z-scheme heterojunction, which significantly inhibited the recombination of charge pairs, induced electron-directed transfer, and promoted better adsorption and activation of N2. This work provides a new perspective for developing high-efficient and low-cost nitrogen fixation catalysts.