摘要
The development of new non-precious metal catalysts and understanding the origin of their activity for the hydrogen evolution reaction （HER） are essential for rationally designing highly active low-cost catalysts as alternatives to state-of-the-art precious metal catalysts. Herein, manganese oxide/hydroxide was demonstrated as a highly active electrocatalysts for the HER by fabricating MnO2 nanosheets coated with Cu2O nanowire arrays （Cu2O@MnO2 NW@NS） on Cu foam followed by an in situ chronopotentiometry （CP） treatment. It was discovered that the in situ transformation of Cu2O@MnO2 into Cu@Mn（OH）2 NW@NS by the CP treatment drastically boosted the catalytic activity for the HER due to an enhancement of its intrinsic activity. Together with the benefits from such （3D） core-sheU arrays for exposing more accessible active sites and efficient mass and electron transfers, the resulting Cu@Mn（OH）2 NW@NS exhibited excellent HER activity and outstanding durability in terms of a low overpotential of 132 mV vs. RHE at 10 mA/cm2, Overall, we expect these findings to generate new opportunities for the exploration of other Mn-based nanomaterials as efficient electrocatalysts and enable further understanding of their catalytic processes.
The development of new non-precious metal catalysts and understanding the origin of their activity for the hydrogen evolution reaction （HER） are essential for rationally designing highly active low-cost catalysts as alternatives to state-of-the-art precious metal catalysts. Herein, manganese oxide/hydroxide was demonstrated as a highly active electrocatalysts for the HER by fabricating MnO2 nanosheets coated with Cu2O nanowire arrays （Cu2O@MnO2 NW@NS） on Cu foam followed by an in situ chronopotentiometry （CP） treatment. It was discovered that the in situ transformation of Cu2O@MnO2 into Cu@Mn（OH）2 NW@NS by the CP treatment drastically boosted the catalytic activity for the HER due to an enhancement of its intrinsic activity. Together with the benefits from such （3D） core-sheU arrays for exposing more accessible active sites and efficient mass and electron transfers, the resulting Cu@Mn（OH）2 NW@NS exhibited excellent HER activity and outstanding durability in terms of a low overpotential of 132 mV vs. RHE at 10 mA/cm2, Overall, we expect these findings to generate new opportunities for the exploration of other Mn-based nanomaterials as efficient electrocatalysts and enable further understanding of their catalytic processes.
基金
This work was financially supported by the National Basic Research Program of China （No. 2015CB932302）, the National Key Research and Development Program of China （No. 2016YFB0101200）, the National Natural Science Foundation of China （Nos. 91645123, 21573249, 21703257 and 21773263）, and the Strategic Priority Research Program of the Chinese Academy of Sciences （No. XDB12020100）. We thank Dr. Z. J. Zhao and Prof. F. Liu at the Center for Analysis and Testing, ICCAS for their help for the XPS analysis.
