▎ 摘　　要

The aim of this study is to investigate the potential of Ti-doped graphene nanoflake (Ti-GNF) for the reduction of CO2 to formic acid by H-2. To get a deeper insight into the mechanism of this reaction, the reliable DFT calculations are performed. It is found that the large positive charge on the Ti atom can greatly regulate the surface reactivity of GNF. The formation of the formate group is the rate determining step for the reduction of CO2. The calculated activation energies demonstrate that Ti-GNF could be utilized as an efficient catalyst for the reduction of CO2 to formic acid. (C) 2017 Elsevier B.V. All rights reserved.