Low-content Pt-triggered the optimized d-band center of Rh metallene for energy-saving hydrogen production coupled with hydrazine degradation

Abstract

Utilizing the hydrazine-assisted water electrolysis for energy-efficient hydrogen production shows a promising application, which relies on the development and design of efficient bifunctional electrocatalysts. Herein, we reported a low-content Pt-doped Rh metallene (Pt-Rhene) for hydrazine-assisted water electrolysis towards energy-saving hydrogen (H2) production, where the ultrathin metallene is constructed to provide enough favorable active sites for catalysis and improve atom utilization. Additionally, the synergistic effect between Rh and Pt can optimize the electronic structure of Rh for improving the intrinsic activity. Therefore, the required overpotential of Pt-Rhene is only 37 mV to reach a current density of −10 mA cm−2 in the hydrogen evolution reaction (HER), and the Pt-Rhene exhibits a required overpotential of only 11 mV to reach a current density of 10 mA cm−2 in the hydrazine oxidation reaction (HzOR). With the constructed HER-HzOR two-electrode system, the Pt-Rhene electrodes exhibit an extremely low voltage (0.06/0.19/0.28 V) to achieve current densities of 10/50/100 mA cm−2 for energy-saving H2 production, which greatly reduces the electrolysis energy consumption. Moreover, DFT calculations further demonstrate that the introduction of Pt modulates the electronic structure of Rh and optimizes the d-band center, thus enhancing the adsorption and desorption of reactant/intermediates in the electrocatalytic reaction.