100 Gram-Scale Organic-free Synthesis of Bi2O2(CO3)2 Nanosheets for High-Selective Formate Production in CO2 Electroreduction

In the realm of CO 2 electrochemical reduction, Bi 2 O 2 CO 3 nanosheets have garnered attention for their ability to selectively produce formate. However, as CO 2 electroreduction technologies advance toward industrial applications, a scalable and green synthesis method is urgently needed. Our research leverages three common Bi-based inorganic salts-BiCl 3 , Bi 2 (SO 4 ) 3 , and Bi(NO 3 ) 3 -as precursors to develop a straightforward process of hydrolysis followed by anions exchange. This method produces high yields of Bi 2 O 2 CO 3 nanosheets without the need for organic solvents or external heating, even at a large scale of ~100 grams, ensuring both sustainability and cost-efficiency. The resulting nanosheets achieved Faradaic efficiencies exceeding 90% across a wide range of potentials for formate production. The combination of innovative synthesis and effective CO 2 conversion underscores the potential of Bi 2 O 2 CO 3 for industrial-scale applications in sustainable energy and chemical production.