Ti/ZnO–Fe2O3 composite: Synthesis, characterization and application as a highly efficient photoelectrocatalyst for methanol from CO2 reduction

In this paper, Ti/ZnO–Fe 2 O 3 composite derived from Ti/Schiff base intercalated ZnFe layered double hydroxides was used as thin film electrode in CO 2 photoelectroreduction. The influence of molar ratio of Ti/Fe and calcination temperature, which would affect the composites' physicochemical property and the photoelectrocatalytic performance for CO 2 reduction, were investigated in detail. The characterization results from XRD, SEM, TEM, UV-vis and BET showed that Ti/ZnO–Fe 2 O 3 composite with flower–like crystal from had small particle sizes, narrow band gap and excellent textural properties. The final product of CO 2 photoelectroreduction was methanol and the intermediates were formic acid and formaldehyde. The methanol field reached at 0.773   mmol/cm 2 after 3   h reaction with 0.5   V voltage by Ti/ZnO–Fe 2 O 3 composite with Ti/Fe   =   1, calcined at 800   °C. In addition, the CO 2 photoelectroreduction pathway and the reason for highly efficient photoelectrocatalytic activity of the composite were also discussed.