Photocatalytic reduction of CO2 to energy products using Cu–TiO2/ZSM-5 and Co–TiO2/ZSM-5 under low energy irradiation

• Cu or Co incorporated TiO2/ZSM-5 catalysts were prepared by a sol–gel method.
• The CO2 conversion properties were studied upon UV irradiation with low energy.
• The methanol is the only obtained product in our study.
• Cu–TiO2/ZSM-5 shows superior CO2 conversion efficiency.
• High photo energy efficiency (PEE) and quantum yield (φ) were reached.

Copper or cobalt incorporated TiO2 supported ZSM-5 catalysts were prepared by a sol–gel method, and then were characterized by XRD, BET, XPS and UV–vis diffuse reflectance spectroscopy. Ti3 + was the main titanium specie in TiO2/ZSM-5 and Cu–TiO2/ZSM-5, which will be oxide to Ti4 + after Co was doped. With the deposition of Cu or Co, the efficiency of the CO2 conversion to CH3OH was increased under low energy irradiation. The peak production rate of CH3OH reached 50.05 and 35.12 μmol g− 1 h− 1, respectively. High photo energy efficiency (PEE) and quantum yield (φ) were also reached. The mechanism was discussed in our study.