Promising transition metal decorated borophene catalyst for water splitting

Borophene has been recently reported to be a promising catalyst for water splitting. However, as a newly synthesized two-dimensional material, there are several issues that remain to be explored. In the present study, we investigate the catalytic performance of three kinds of pristine and decorated borophenes using first-principles calculations. Our calculations show that Ni-doped alpha borophene can be a highly active catalyst for water splitting. Doping or decorating with different transition metals such as Co or Ni at different sites shows a strong effect on the catalytic performance of alpha, beta(12) and chi(3) borophenes. Ni-doped alpha borophene shows low Gibbs free energy of hydrogen adsorption (Delta G(H) similar to 0.055 eV) for the hydrogen evolution reaction (HER) and promising overpotential (0.455 V) for the oxygen evolution reaction (OER). This study provides some critical insights into the catalytic activity of borophene for water splitting by selecting suitable decorated metal.