Wang Xuejiao, Bai Jingyuan, Zhang Meilin, Chen Yuxi, Fan Longyi, Yang Zhou, Zhang Jin, Guan Renguo
School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China.
Key Laboratory of Near-Net Forming of Light Metals of Liaoning Province, Dalian Jiaotong University, Dalian 116028, China.
Nanomaterials (Basel). 2023 Jan 25;13(3):491. doi: 10.3390/nano13030491.
Nanostructuring of metals is nowadays considered as a promising strategy towards the development of materials with enhanced electrochemical performance. Porous and fully dense CuNi films were electrodeposited on a Cu plate by electrodeposition in view of their application as electrocatalytic materials for the hydrogen evolution reaction (HER). Porous CuNi film were synthesized using the hydrogen bubble template electrodeposition method in an acidic electrolyte, while fully dense CuNi were electrodeposited from a citrate-sulphate bath with the addition of saccharine as a grain refiner. The prepared films were characterized chemically and morphologically by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). The Rietveld analysis of the XRD data illustrates that both CuNi films have a nanosized crystallite size. Contact angle measurements reveal that the porous CuNi film exhibits remarkable superhydrophobic behavior, and fully dense CuNi film shows hydrophilicity. This is predominately ascribed to the surface roughness of the two films. The HER activity of the two prepared CuNi films were investigated in 1 M KOH solution at room temperature by polarization measurements and electrochemical impedance spectroscopy (EIS) technique. Porous CuNi exhibits an enhanced catalysis for HER with respect to fully dense CuNi. The HER kinetics for porous film is processed by the Volmer-Heyrovsky reaction, whereas the fully dense counterpart is Volmer-limited. This study presents a clear comparison of HER behavior between porous and fully dense CuNi films.
如今，金属的纳米结构化被认为是开发具有增强电化学性能材料的一种有前景的策略。考虑到其作为析氢反应（HER）的电催化材料的应用，通过电沉积在铜板上制备了多孔和全致密的CuNi薄膜。多孔CuNi薄膜是在酸性电解质中使用氢气泡模板电沉积法合成的，而全致密的CuNi是在添加糖精作为晶粒细化剂的柠檬酸盐 - 硫酸盐浴中电沉积的。通过扫描电子显微镜（SEM）、能量色散X射线光谱（EDX）和X射线衍射（XRD）对制备的薄膜进行化学和形态表征。XRD数据的Rietveld分析表明，两种CuNi薄膜都具有纳米级微晶尺寸。接触角测量表明，多孔CuNi薄膜表现出显著的超疏水行为，而全致密CuNi薄膜表现出亲水性。这主要归因于两种薄膜的表面粗糙度。通过极化测量和电化学阻抗谱（EIS）技术在室温下于1 M KOH溶液中研究了两种制备的CuNi薄膜的HER活性。相对于全致密CuNi，多孔CuNi对HER表现出增强的催化作用。多孔薄膜的HER动力学由Volmer - Heyrovsky反应控制，而全致密薄膜则受Volmer限制。本研究对多孔和全致密CuNi薄膜之间的HER行为进行了清晰的比较。
