ZnIn2S4 nanosheet growth on amine-functionalized SiO2 for the photocatalytic reduction of CO2

The photocatalytic reduction of CO2 into valuable fuels and sustainable energy has a promising future, yet remains a challenge due to low charge separation efficiency and inadequate active sites. We find that ZnIn2S4-loaded secondary amine-functionalized organic silica (ZnIn2S4/NH–SiO2) was effective for visible-light driven CO2 photocatalytic reduction. The ZnIn2S4/NH–SiO2 with 40% ZnIn2S4 content achieves a CO production rate of 1304.8 μmol g−1 h−1 at room temperature, which is about 3 times higher than that of pristine ZnIn2S4. The thin ZnIn2S4 nanosheet accelerates the separation of photogenerated electron pairs, and the amine groups on ZnIn2S4/NH–SiO2 act as active sites for adsorption and activation of CO2, hence facilitating the photoreduction of CO2.