Tunable HER activity from doping and strain strategies for β-Sb monolayer: DFT calculations

The hydrogen evolution reaction of transition metal-doped beta-Sb monolayers have been systematically investigated with DFT calculations in this work. Remarkably, the calculated hydrogen adsorption free energy of V doped beta-Sb monolayer was reduced to 0.06 eV, which is comparable to the well-known highly efficient catalyst of Pt metal. The tunable hydrogen adsorption ability was linearly correlated with the d(z)2 band center of surface TM dopants in beta-Sb monolayer. In addition, the strain engineering on the hydrogen evolution reaction activity of Ni doped beta-Sb monolayer was also explored here. A tensile strain of 6% endows the Ni doped beta-Sb catalyst with optimum HER activity. These insights provide an important strategy for designing low-cost beta-Sb nano-catalyst with high HER activity for water-splitting.