Abstract
For reduction of CO2 into hydrocarbon fuels, an AgFeNi2S4-Graphene-TiO2 ternary nanocomposite material was synthesized via the Pechini method. The Pechini method is based on a chelating agent which, together with ethylene glycol (C2H6O2) and citric acid (C6H8O7) as a chelating cation, can affect the structure and stability of the nanocomposite. The catalytic activity of the photocatalyst for photocatalytic and electrochemical CO2 evolution into hydrocarbon fuels was tested. The methanol yield under UV light was 8.679 %, 6.349 %, and 4.136 %, and the methanol yields under visible light was 6.291 %, 4.738 %, and 2.339 %, respectively. The stability and reusability of the photocatalyst remained high after a 4-cycle recycling test without a decrease in yield of the final photocatalytic CO2 reduction product. The enhanced photoreduction of CO2 through the as-prepared ternary photocatalyst can be ascribed to the catalyst's conformation and low recombination rate. In electrochemical CO2 reduction, the Faraday efficiency is the main parameter that defines the performance of the working electrode and the evolution of methanol. The Faraday efficiency of AFNSGT ternary nanocomposite was 44.25 %; this is an increase in the value of the Faraday efficiency, which proves that the design of the new nanocomposite successfully increases the activity of the working electrode and has a positive effect on the electrochemical reduction of CO2. The photocatalytic and electrochemical CO2 reduction data show that the preparation method, morphological state, and charge carrier properties of the photocatalyst are important for the catalytic activity and efficiency of the methanol evolution pathway. This study provides a strategy for fabrication of a new ternary nanocomposite based on 2D-structured graphene, TiO2, and a quaternary nanocomposite.
Novel Combination of Quaternary AgFeNi2S4 Semiconductor In Graphene-TiO2 Nanocomposite For The Enhanced Electrophotocatalytic Reduction of CO2