Sun Yan, Chen Gongjin, El Bachraoui Fatima, Cui Yingdan, Liu Guimei, Xiao Fei, Qian Xitang, Xu Zhiwen, Shao Minhua
Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, 999077, China.
CIAC-HKUST Joint Laboratory for Hydrogen Energy, Energy Institute, The Hong Kong University of Science and Technology, Clear Watery Bay, Kowloon, Hong Kong SAR, 999077, China.
Small Methods. 2025 Aug;9(8):e2500103. doi: 10.1002/smtd.202500103. Epub 2025 Mar 30.
A facile and universal strategy is employed to synthesize Ag decorated NiCo layered double hydroxide (LDH) heterogeneous structure for the oxygen evolution reaction (OER). The Ag nanoparticles are deposited on NiCo LDH nanosheets via a spontaneous redox reaction. The synthesized Ag/NiCo LDH achieves an overpotential of 460 mV at a current density of 1 A cm , surpassing that of NiCo LDH (722 mV). In an anion exchange membrane water electrolyzer (AEMWE) with Ag/NiCo LDH as the anode and Pt/C as the cathode, the cell can deliver an ultrahigh current density of 5 A cm at a low voltage of 2.10 V. This superior current density is nearly four times larger than that of AEMWEs with other non-precious anode electrocatalysts reported in literature under the same effective area. Furthermore, it exhibits desired durability with no performance decay for over 300 h at 1 A cm, which is almost six times longer than that of electrolyzer with an IrO anode. Operando electrochemical impedance spectroscopy results reveal that Ag decoration facilitates active site formation and reduces the OER onset potential compared to NiCo LDH. This study showcases a practical approach to designing highly effective and durable OER electrocatalysts in industrial hydrogen production.
采用一种简便通用的策略合成用于析氧反应（OER）的Ag修饰的NiCo层状双氢氧化物（LDH）异质结构。通过自发氧化还原反应将Ag纳米颗粒沉积在NiCo LDH纳米片上。合成的Ag/NiCo LDH在电流密度为1 A cm时的过电位为460 mV，超过了NiCo LDH的过电位（722 mV）。在以Ag/NiCo LDH为阳极、Pt/C为阴极的阴离子交换膜水电解槽（AEMWE）中，该电解槽在2.10 V的低电压下可提供5 A cm的超高电流密度。在相同有效面积下，这种优异的电流密度几乎是文献报道的其他非贵金属阳极电催化剂的AEMWE的四倍。此外，它表现出所需的耐久性，在1 A cm下超过300 h无性能衰减，这几乎是具有IrO阳极的电解槽的六倍。原位电化学阻抗谱结果表明，与NiCo LDH相比，Ag修饰促进了活性位点的形成并降低了OER起始电位。这项研究展示了一种在工业制氢中设计高效耐用的OER电催化剂的实用方法。
