In situ transformation of Cu2O@MnO2 to Cu@Mn(OH)2 nanosheet-on-nanowire arrays for efficient hydrogen evolution
hydrogen evolution reaction (HER), water electrolysis, electrocatalysis, manganese oxides, manganese hydroxides
ABSTRACT 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 three-dimensional (3D) core–shell 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.
Tsinghua University Press
Li Chen,Xing Zhang,Wenjie Jiang,Yun Zhang,Linbo Huang,Yuyun Chen,Yuguo Yang,Li Li,Jinsong Hu, In situ transformation of Cu2O@MnO2 to Cu@Mn(OH)2 nanosheet-on-nanowire arrays for efficient hydrogen evolution. NanoRes.2018, 11(4): 1798–1809