Reduction of carbon dioxide to methane and ethanol on the surface of graphyne-like boron nitride (BNyen) monolayer: A DFT study

Recently, scientists have created a novel type of boron nitride material known as BNyen. This material is similar in structure to Graphyne and has a higher N:B ratio than traditional boron nitride due to the addition of boron and nitrogen connecting segments within its units. This material has been studied for its potential as a photo- catalyst for reduction of CO2 2 using DFT approaches. Optical and electronic attributes of BNyen suggest that it has a wider visible-light range and a band gap of 5.69 eV. By adding boron to BNyen, patial distributions of LUMO and HOMO indicate that pi network has been extended, resulting in significantly greater photocatalytic efficiency. Upon the adsorption of CO2 2 on BNyen monolayer, the band gap significantly decreases, indicating a strong interaction between the BNyen and CO2. 2 . DFT computations were employed to explore the mechanism of CO2 2 reduction to a single carbon product catalyzed by BNyen. Based on the Delta G values, the optimized pathway for this reduction is from CO2 2 to CH4. 4 . Additionally, the potential formation of di-carbon products was considered, and based on the free energy values, CH3CH2OH 3 CH 2 OH is identified as the final di-carbon product. The Gibbs free energies for potential CO2 2 reaction pathways on BNyen were calculated, revealing that CO2 2 can be reduced to CH4 4 with a low limiting potential of-0.37 V and to CH3CH2OH 3 CH 2 OH with a low limiting potential of-0.57 V, both processes being powered by solar energy. In CO2RR, 2 RR, the competing hydrogen evolution reaction (HER) must be considered. The free energy of HER (Delta G Delta G = 0.96 eV) is significantly higher than the Delta G of the rate-determining steps for the mono-carbon product (0.37 eV) and the di-carbon product (0.57 eV) on BNyen. Therefore, BNyen effectively suppresses HER during the CO2RR 2 RR process. This research can serve as a valuable guide for developing novel types of BNyen as appropriate photocatalysts for CO2 2 reduction reactions (CO2RR). 2 RR).