Speaker
Description
The biggest challenge in the commercial application of electrochemical reduction of water through the hydrogen evolution reaction (HER) is hampered due to the scarcity of inexpensive and efficient catalysts. Herein, we propose a metal-free biphenylene nanosheet, a recently proposed two- dimensional (2D) carbon allotrope [Science 372.6544 (2021)], as an excellent HER electrocatalyst. The dynamical and thermal stability of biphenylene nanosheet is validated through phonon dispersion and ab-initio molecular dynamics (AIMD) calculations, respectively. The first-principles calculations show that the biphenylene nanosheet is a metal, having Pz orbitals at the Fermi level. At a low H coverage (1/54), the biphenylene nanosheet shows excellent catalytic activity with the adsorption Gibbs free energy (ΔG H ) of 0.082 eV. The B-doping and C-vacancy in biphenylene further improve the ΔG H to 0.016 eV and 0.005 eV, respectively. The strength of interactions between the H atom and the nanosheet is explained through the relative position of the p-band center. Our study opens new possibilities to use non-metallic porous materials as highly efficient electrocatalysts for HER.
