Production of renewable fuels by the photohydrogenation of CO₂: effect of the Cu species loaded onto TiO₂ photocatalysts

Abstract

The efficient gas phase photocatalytic hydrogenation of CO2 into a desirable renewable fuel was achieved using a Cu-loaded TiO2 photocatalyst system. Enhancing the amount of Ti(3+) relative to Ti(4+) in a Cu-loaded TiO2 photocatalyst provided an excellent opportunity to promote the photohydrogenation of CO2. The coexistence of Cu and Cu(+) species during the photoreaction was shown to efficiently enhance the photocatalytic activity by prolonging the lifetime of the electrons. To achieve the best photoactivity, the Cu species must be maintained at an appropriately low concentration (≤1 wt%). The highest CH4 yield obtained was 28.72 μmol g(-1). This approach opens a feasible route not only to store hydrogen by converting it into a desirable renewable fuel, but also to reduce the amount of the greenhouse gas CO2 in the atmosphere.

Efficient approach for simultaneous CO and H2 production via photoreduction of CO2 with water over copper nanoparticles loaded TiO2

“…Chen et al recently reported CO 2 6 hydrogenation to maximum 28.72 μmol g -1 methane over Cu modified TiO 2 under UV-C irradiation. They showed presence of Cu and Cu + species and ratio of Ti +3 with respect to Ti +4 enhances the photoactivity [21]. Tan et al have prepared copper nanoparticles decorated TiO 2 nanorod films using electrochemical method for reduction of CO 2 to methane (2.91 ppm g -1 h -1 catalyst) [22].…”

N‐Methylation of N‐Methylaniline with Carbon Dioxide and Molecular Hydrogen over a Heterogeneous Non‐Noble Metal Cu/TiO2 Catalyst

“…Recently, Cu/TiO 2 catalyst was reported to be effective for photocatalytic CO 2 reduction, in which the Cu + and Cu 0 species formed by H 2 ‐reduction was confirmed to be more active in charge separation than Cu + species alone . Cu/TiO 2 was also used in the photocatalytic hydrogenation of CO 2 into CH 4 and the coexistence of Cu 0 and Cu + was beneficial to enhance the activity by prolonging the lifetime of electrons …”

“…[19] Cu/ TiO 2 was also used in the photocatalytic hydrogenation of CO 2 into CH 4 and the coexistence of Cu 0 and Cu + was beneficial to enhance the activity by prolonging the lifetime of electrons. [20] Considering the above-mentioned results, we have investigated the feasibility of Cu catalyst for direct N-methylation of N-methylaniline (MA) with CO 2 and H 2 . In the present work, TiO 2 (P25) was employed as a support to disperse Cu species and Cu/TiO 2 samples were prepared by deposition-precipitation method and tested for the target reaction in n-octane.…”

Dynamic photocatalytic reduction of CO 2 to CO in a honeycomb monolith reactor loaded with Cu and N doped TiO 2 nanocatalysts

“…As a consequence, higher photoactivity could be seen over Cu/TiO 2 monolithic photocatalyst for CO production. Recently, similar observations have been reported for photocatalytic CO 2 reduction to CO and CH 4 over Cu/TiO 2 photocatalyst in a gas phase system [43].…”