Synthesis of CoFe2O4-modified g-C3N4 with enhanced photocatalytic performance for nitrogen fixation

摘要

CoFe2O4-modified graphitic carbon nitride heterogeneous catalyst was successfully synthesized by a convenient decomposition-thermal polymerization method, to improve the efficiency of N-2 photo-fixation with solar energy as the only driving force. The photocatalytic nitrogen fixation efficiency of 2% CoFe2O4-modified g-C3N4 was 313 mg/L/g(cat) with excellent reusability and stability, which was 2.5 times as high as that of bulk g-C3N4 (125 mg/L/g(cat)). The significant enhancement of photoactivity over 2% CoFe2O4-modified g-C3N4 is ascribed to the narrower band gap, higher separation efficiency of photogenerated charge carriers, and the existence of nitrogen defects. The mechanism of photocatalytic nitrogen fixation is discussed in detail.