▎ 摘　　要

The development of CO2 into hydrocarbon fuels has emerged as a green method that could help mitigate global warning. The novel structured photocatalyst is a promising material for use in a photocatalytic and magneto-electrochemical method that fosters the reduction of CO2 by suppressing the recombination of electron-hole pairs and effectively transferring the electrons to the surface for the chemical reaction of CO2 reduction. In our study, we have developed a novel-structured AgCuZnS2-graphene-TiO2 to analyze its catalytic activity toward the selective evolution of CO2. The selectivity of each nanocomposite substantially enhanced the activity of the AgCuZnS2-graphene-TiO(2 )ternary nanocomposite due to the successful interaction, and the selectivity of the final product was improved to a value 3 times higher than that of the pure AgCuZnS2 and 2 times higher than those of AgCuZnS2-graphene and AgCuZnS2-TiO2 under ultraviolet (UV)-light (lambda = 254 nm) irradiation in the photocatalytic process. The electrochemical CO2 reduction test was also conducted to analyze the efficacy of the AgCuZnS2-graphene-TiO2 when used as a working electrode in laboratory electrochemical cells. The electrochemical process was conducted under different experimental conditions, such as various scan rates (mV.s(-1)), under UV-light and with a 0.07 T magnetic-core. The evolution of CO2 substantially improved under UV-light (lambda = 254 nm) and with 0.07 T magnetic-core treatment; these improvements were attributed to the facts that the UV-light activated the electron-transfer pathway and the magnetic core controlled the pathway of electron-transmission/prevention to protect it from chaotic electron movement. Among all tested nanocomposites, AgCuZnS2-graphene-TiO2 absorbed the CO2 most strongly and showed the best ability to transfer the electron to reduce the CO2 to methanol. We believe that our newly-modeled ternary nanocomposite opens up new opportunities for the evolution of CO2 to methanol through an electrochemical and photocatalytic process.