Through a simple redox reaction, the precursor of Ni (OH)2 mixed with SnO2 was in situ transformed into a core-shell structure with elemental Ni blend SnO2 as the core and nickel metaborate as the shell. The metaborate shell is an excellent adsorption site for water molecules, which paves the way for subsequent hydride adsorption. When a small amount of SnO2 is mixed with elemental Ni, the electronic structure is optimized, and the electron enrichment of Ni is realized, making the hydrogen adsorption performance better. This core-shell synergy promotes the Vomer step in HER, thereby enhancing HER performance. In addition, Ni–Sn@NiBO/NF possesses larger electrochemical surface area and smaller charge transfer resistance. Only an overpotential of 22 mV is needed to drive a current density of 10 mA cm−2, indicating the excellent HER performance of the Ni–Sn@NiBO/NF catalyst. At high current density of 50 mA cm−2, the overpotential is only 79 mV. When Ni–Sn@NiBO/NF is used as the bifunctional catalyst for coupling HER and OER, the voltage is only 1.595 V at 10 mA cm−2. It shows that the catalyst has great application potential in electrocatalytic water decomposition to produce hydrogen.

中文翻译：

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构建 Ni-SnO2 核涂层非晶态 Ni（BO2）2 壳层促进水分解以制氢


通过简单的氧化还原反应，Ni （OH）2 的前驱体与 SnO2 混合，原位转化为以元素 Ni 共混 SnO2 为核心，以偏硼酸镍为壳层的核壳结构。代谢物壳层是水分子的极好吸附位点，为后续的氢化物吸附铺平了道路。当少量 SnO2 与元素 Ni 混合时，电子结构得到优化，实现了 Ni 的电子富集，使氢吸附性能更好。这种核壳协同作用促进了 HER 中的 Vomer 步骤，从而提高了 HER 性能。此外，Ni-Sn@NiBO/NF 具有更大的电化学表面积和较小的电荷转移电阻。只需 22 mV 的过电位即可驱动 10 mA cm-2 的电流密度，表明 Ni-Sn@NiBO/NF 催化剂具有出色的 HER 性能。在 50 mA cm−2 的高电流密度下，过电位仅为 79 mV。当 Ni–Sn@NiBO/NF 用作偶联 HER 和 OER 的双功能催化剂时，在 10 mA cm-2 时电压仅为 1.595 V。这表明该催化剂在电催化水分解制氢方面具有很大的应用潜力。