Controlled Synthesis of Cu 0 /Cu 2 O for Efficient Photothermal Catalytic Conversion of CO 2 and H 2 O

Sustainable conversion of CO 2 and H 2 O to fuels using solar energy is highly attractive for clean fuel production. This work focuses on the one-pot synthesis of bifunctional Cu 0 /Cu 2 O catalysts for the photothermal conversion of CO 2 and H 2 O. The experimental results show that the Cu 0 /Cu 2 O catalysts with a Cu 0 /Cu 2 O interface and a controllable ratio of Cu 0 to Cu 2 O can be readily synthesized by tuning the ratio of the Cu precursor to the reductant (N 2 H 4 ). The activity of the prepared Cu 0 /Cu 2 O catalysts in the photothermal catalytic conversion of CO 2 and H 2 O is greatly influenced by the ratio of Cu 0 to Cu 2 O and the reaction temperature. Cu 0 /Cu 2 O-R2, a catalyst prepared with a Cu precursor to N 2 H 4 ratio of 1:2, exhibited the highest activity, i.e., 13.2 μmol g –1 h –1 of CO and 2.6 μmol g –1 h –1 of CH 3 OH at 383 K, which is much higher than those of Cu 2 O or Cu. Such enhanced performance is attributed to the formation of the interface between Cu 0 and Cu 2 O, which is beneficial not only to photocatalysis but also to thermocatalytic CO 2 hydrogenation. This work illustrates that a bifunctional catalyst with mixed metal oxidation states can be prepared by a one-pot method and is efficient for improving the performance of the directly coupled photothermal catalytic conversion of CO 2 and H 2 O.