Boron-rich boron nitride nanomaterials as efficient metal-free catalysts for converting CO2 into valuable fuel

Abstract

Searching for low-cost and metal free catalysts for efficient reduction of CO2 is urgent because metal free catalysts have many advantages, such as high stability and environmental friendly. Based on the comprehensive density functional theory (DFT) calculations of CO2 conversion on boron nitride nanomaterials, the results indicate that the pristine boron nitride nanosheet (BNNS) and boron nitride nanotube (BNNT) cannot efficiently activate CO2, while boron-rich BNNS and BNNT can efficiently convert CO2 to CH4 with very low limiting potentials of −0.27 V and −0.23 V, respectively. In addition, the studies of Mulliken charge analysis of these catalysts also indicate that the two boron-rich structures prefer to donating electrons to CO2 and result in the efficient activation of the C = O double bonds, which promote the activation of CO2 and the following conversion. Moreover, the better performance of CO2 reduction on the B-rich BNNT indicates that the curvature of the surface can further improve its catalytic activity.