Qiuyu Chen et al. / Chinese Journal of Catalysis 41 (2020) 514–523
521
were well-fitted with double exponential functions. The aver-
catalytic CO2 reduction catalyst based on a one-fold improve-
ment in the photoactivity. This work reveals that g-C3N4-based
composites offer promise for important applications in the field
of energy conversion and environmental purification.
age lifetime (τ) was determined using the formula
2
2
i1Ai2
/
i1Ai
[58]. Clearly, the carrier lifetime of
i
i
Co-CN2, which was 1759.7 ns, was much higher than that of CN
(1348.0 ns), which suggested more effective electron-hole pair
generation in the case of the former. The above analysis
showed that Co-CN2 photocatalyst is beneficial for charge
transfer and separation.
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Scheme 1. A possible mechanism of CO2 photoreduction.