Salt Template Based Synthesis of Bi Nanoparticles and Their Electrochemical CO2RR Activity for Formic Acid Production

Fossil fuel combustion process has led to excess emission of carbon dioxide to air about 35 billion ton per year. It causes serious environmental crisis like global warming, acid rain, water pollution etc. Up to now, considerable strategies for reducing usage of fossil fuels are mostly focused on expanding renewable energy source (energy harvesting, green hydrogen, power generation from nature). But it is not sufficient for supplying increasing global energy demand[1] and for these reason, continuous CO₂ emission to atmosphere is inevitable. Carbon capture and utilization technology(CCUS) is rising as one of the most effective solution to these unavoidable combustion process. Among CCUS technology, Electroreduction of CO₂ to fuel (CO2RR) which can be achieved from catalytic conversion at heterogeneous interface is promising technology because CO₂ can be transformed to other value-added multi carbon products. Formic acid, which is most high value-added products, can be synthesized through flow-cell set-up what can make CO2 gas diffuses more easily to the catalytic active site. We coated Bismuth nanoparticle as active catalyst directly on Gas diffusion electrode by NaCl template method without adding any binder solution and checked the selectivity, efficiency of bismuth catalyst layer by analyzing final products using NMR, Gas chromatography spectroscopy method. The synthesized Bi NPs exhibits excellent selectivity to HCOOH(~90%) at -0.8V, and showed over than 30mA/cm²current density.