we have successfully fabricated ternary Au@N-doped graphene decorated-TiO2 (ANGT-x) heterostructure catalysts by a multistep preparation process and demonstrated for solar-light-switched CO2 reduction towards CH4 production with high selectivity using a gas-phase, batch reactor system. Successful formation of the composite was confirmed by XRD, STEM, Raman, and XPS analysis; UV-Vis-DRS, PL, TPR and EIS analysis confirmed improved optical properties and successful charge migration among the catalysts. Meanwhile, Au NPs act as electron sinks to promote catalytic activity; therefore, the optimized sample ANGT2 delivers the highest Relectron of 742.39 µmol g-1 h-1 in 4 h under the visible-light irradiation. Most importantly, the catalytic activity was ≈4 and ≈60 folds higher than ANGT0 and AT2, respectively. The catalyst displayed the photostability of up to 3 cycles. The enhanced catalytic activity and stability of ANGT2 attributed to increased visible light absorption, improved charge separation, and unwanted charge recombination. The post-catalytic analysis also proves that the catalyst’s chemical stability is well enough to use long-term applications. The in-depth photocatalytic CO2 reduction mechanism over the catalyst has been well demonstrated by orderly characterization techniques, including bandgap measurement, Mott-Schottky plots, and Valance band spectra. The absence of other possible products such as H2 and less amount of CO suggests the selectivity and reaction pathway of the CO2 reduction process.
The proposed research is closely connected to two major alarming concerns of present times: global energy crisis and environmental pollution. Due to the high significance of this topic in our modern society, the impact of the proposed research on the scientific community as well as industry is going to be huge within Europe as well as throughout the world. As a result it is anticipated that the outcomes of research will attain good citation rates soon after publication. Benefitting from the new ideas of the PCO2R proposal will ensure establishing intellectual property rights through filing patents and copyrights or in some case treating the idea as a trade secret depending on the research outcomes. Consequently the importance and high quality of the proposed research will help me to establish as a world-class expert in the field of chemical engineering and materials science which is very crucial for my individual growth as an independent scientific researcher. The results of this project would be of immediate interest to the scientific community and industry, at a later stage it is bound to connect with the general public because of the long run impacts of CO2 reduction from atmosphere on global climate and environment.
