A porphyrin-based metal organic framework for high rate photoreduction of CO2 to CH4 in gas phase

In the current study, porphyrin-based metal organic framework (Zn/PMOF) was prepared using tetrakis (4-carboxy phenyl) porphyrin (TCPP) as ligand and characterized by different spectra analyses. The FESEM and EDX measurements revealed the successful formation of a Zn/PMOF. The CO2 photoreduction experiments were carried out over Zn/PMOF in the presence of H2O vapor as photocatalyst and sacrificial electron donor, respectively, under UV/Visible light. The reaction products results showed that 10.43 μmol CH4 was produced over Zn/PMOF during the 4 h photocatalytic reaction under UV/Visible illumination where is 80.6% greater than bare ZnO under the same reaction condition. The stability and reusability of Zn/PMOF were investigated via recycling test and there were not significant losses of photocatalytic activities even after three cycles. In addition, UV-vis spectra and FTIR measurement showed no significant changes in photocatalyst structure. Finally, deactivation of the photocatalyst and the mechanism of the reaction were determined.