Tandem Synergistic Catalysis on Cu-Pd/BiTiO Nanorods Promoting Highly Selective Photoconversion of CO to Ethyl Alcohol.

The production of high-energy-density liquid fuels through the photoconversion of CO offers a highly efficient method for storing sustainable solar energy for future use. BiTiO (BTO) nanorods loaded with Cu-Pd nanoalloys were designed for the highly selective photoreduction of CO to ethyl alcohol, using HO as the proton source. A tandem synergistic catalysis mechanism was proposed for this CO photoconversion process. Initially, *CO intermediates are produced at the BTO nanorod, then transfer to neighboring Cu atoms, where they convert into ethyl alcohol via C-C bond formation on Pd atoms. Adjusting the ratio of Cu to Pd can modify the binding strength of the intermediates on the catalyst surface and the reaction kinetics of the CO reduction, thus optimizing the efficiency and selectivity of the products. With the substitution of TiO, CeO, and SiO for the BTO nanorod in similar systems, only CO or CH were produced, highlighting the essential role of BTO in the present CO photoconversion. Additionally, thermal-assisted photocatalysis was also tested to lower the free energy barrier for the formation of the *OCCO intermediate, crucial for ethyl alcohol production, and enhance charge separation in BTO, leading to a 2.7-fold improvement compared to that under light illumination alone. A photocatalytic CO reduction device was well designed with a reaction area of 25 cm × 25 cm, providing a potential model for large-scale ethyl alcohol production from the photoconversion of CO. This research may pave the way for utilizing the synergistic effects of metal active sites and photocatalyst substrates to enhance the generation of multicarbon species from CO reduction.