The most abundant rare earth metals in the Earth's crust have received considerable recent attention as efficient electrocatalysts for full water splitting, but it is highly desired to explore a new strategy to improve their catalytic activity. In this communication, we report the development of nanoporous CeO₂ nanowire array on Ti mesh (np-CeO₂/TM) derived from MnO₂–CeO₂/TM via an acid etching strategy, and MnO₂ acts as a pore-forming agent through selective etching with oxalic acid. As a rare earth metal catalyst, np-CeO₂/TM needs an overpotential of 91 mV for the hydrogen evolution reaction (HER) and 279 mV for the oxygen evolution reaction (OER) to drive a current density of 10 mV cm⁻² in 1.0 M KOH, 93 mV and 101 mV less than that needed by MnO₂–CeO₂/TM, respectively. We also demonstrate the use of np-CeO₂/TM to make a two-electrode electrolyzer capable of driving 10 mV cm⁻² at a cell voltage of 1.57 V.

中文翻译：

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在碱性条件下通过纳米多孔CeO2纳米线阵列将水完全分解

地壳中最丰富的稀土金属作为有效的全水分解电催化剂，最近受到了相当大的关注，但是迫切需要探索一种提高其催化活性的新策略。在本次交流中，我们报告了通过酸蚀刻策略在源自MnO ₂ -CeO ₂ / TM的Ti网格（np-CeO ₂ / TM）上开发纳米多孔CeO ₂纳米线阵列的过程，其中MnO ₂充当成孔剂通过使用草酸进行选择性蚀刻。np-CeO ₂作为稀土金属催化剂/ TM对于氢析出反应（HER）需要91 mV的过电势，对于氧析出反应（OER）需要279 mV的过电势，以在1.0 M KOH中驱动10 mV cm ^-2的电流密度，低于93 mV和101 mV分别需要MnO ₂ -CeO ₂ / TM。我们还演示了使用np-CeO ₂ / TM制作双电极电解槽，该电解槽能够在1.57 V的电池电压下驱动10 mV cm ^-2。