Abstract Iridium–nickel (Ir–Ni) film is of great interest for catalytic and corrosive environment applications. Ir–Ni thin films as an electrocatalyst for hydrogen evolution reaction (HER) were galvanostatically electrodeposited on copper (Cu) foam from an electrolyte containing 13.5 mM sodium hexabromoiridate(III) and 40.5 mM Ni sulphate hexahydrate, simultaneously compared with electrodeposited Ir and Ni thin films. The top surface morphology of the film was characterized by scanning electron microscopy. The chemical composition of the film was determined by energy-dispersive spectroscopy and X-ray photoelectron spectroscopy. The electrocatalytic performance was performed by linear sweep voltammogram and cyclic voltammetry. The results showed that Ir–Ni thin film adhered to Cu foam and the surface appeared much rougher than the surface of Ni film. The chemical composition of Ir in the deposit was 80 ± 1.2 at.%. The film was composed of nanograins. The top surface of as-deposited film was mainly composed of metallic state. However, the top surface of the film consisted of oxides states, such as Ni oxides or Ni(OH) 2 , and Ir oxides after electrochemical measurements. As-deposited Ir–Ni thin film with large real active area exhibited high efficient electrocatalytic activity for HER, and achieved a current density of 10 mA cm 2 at an overpotential of 60 mV and a Tafel slope of 40 mV dec −1 , which is superior to pure Ir and Ni thin films. The remarkable increase in electrocatalytic activity for Ir–Ni film was ascribed to both increased surface area of active centers due to relatively rough and electrocatalytic synergism of Ir and Ni for the HER. Graphic Abstract Ir–Ni thin film electrodeposited on a foam copper electrode was used as an electrocatalyst for HER. The surface of as-deposited film was composed of metallic state. As-deposited Ir–Ni thin film with large real active area exhibited high efficient electrocatalytic activity for HER, and achieved a current density of 10 mA cm 2 at an overpotential of 60 mV and a Tafel slope of 40 mV dec −1 , which is superior to pure iridium and Ni thin films. As-deposited film possessed a good stability by accelerated degradation studies.

中文翻译：

---

薄膜 Ir-Ni 电催化剂在铜泡沫上的恒电流电沉积在碱性电解质中的 HER 性能

摘要 铱-镍 (Ir-Ni) 薄膜在催化和腐蚀环境应用中具有重要意义。将 Ir-Ni 薄膜作为析氢反应 (HER) 的电催化剂从含有 13.5 mM 六溴化钠 (III) 和 40.5 mM 硫酸镍六水合物的电解质中恒电流电沉积在铜 (Cu) 泡沫上，同时与电沉积的 Ir 和 Ni 薄膜进行比较电影。通过扫描电子显微镜表征膜的顶表面形态。通过能量色散光谱和X射线光电子能谱测定薄膜的化学成分。电催化性能通过线性扫描伏安法和循环伏安法进行。结果表明 Ir-Ni 薄膜粘附在 Cu 泡沫上，表面看起来比 Ni 薄膜的表面粗糙得多。沉积物中 Ir 的化学成分为 80 ± 1.2 at.%。该薄膜由纳米颗粒组成。沉积膜的顶面主要由金属态组成。然而，在电化学测量后，薄膜的顶面由氧化物状态组成，例如Ni氧化物或Ni(OH) 2 和Ir氧化物。具有大实际活性面积的沉积态 Ir-Ni 薄膜对 HER 表现出高效的电催化活性，在 60 mV 的过电位和 40 mV dec -1 的 Tafel 斜率下实现了 10 mA cm 2 的电流密度，即优于纯 Ir 和 Ni 薄膜。Ir-Ni 膜电催化活性的显着增加归因于由于相对粗糙的 Ir 和 Ni 对 HER 的电催化协同作用而增加了活性中心的表面积。图形摘要 电沉积在泡沫铜电极上的 Ir-Ni 薄膜用作 HER 的电催化剂。沉积膜的表面由金属态组成。具有大实际活性面积的沉积态 Ir-Ni 薄膜对 HER 表现出高效的电催化活性，在 60 mV 的过电位和 40 mV dec -1 的 Tafel 斜率下实现了 10 mA cm 2 的电流密度，即优于纯铱和镍薄膜。通过加速降解研究，沉积的薄膜具有良好的稳定性。图形摘要 电沉积在泡沫铜电极上的 Ir-Ni 薄膜用作 HER 的电催化剂。沉积膜的表面由金属态组成。具有大实际活性面积的沉积态 Ir-Ni 薄膜对 HER 表现出高效的电催化活性，在 60 mV 的过电位和 40 mV dec -1 的 Tafel 斜率下实现了 10 mA cm 2 的电流密度，即优于纯铱和镍薄膜。通过加速降解研究，沉积的薄膜具有良好的稳定性。图形摘要 电沉积在泡沫铜电极上的 Ir-Ni 薄膜用作 HER 的电催化剂。沉积膜的表面由金属态组成。具有大实际活性面积的沉积态 Ir-Ni 薄膜对 HER 表现出高效的电催化活性，在 60 mV 的过电位和 40 mV dec -1 的 Tafel 斜率下实现了 10 mA cm 2 的电流密度，即优于纯铱和镍薄膜。通过加速降解研究，沉积的薄膜具有良好的稳定性。并在60 mV的过电位和40 mV dec -1 的Tafel斜率下实现了10 mA cm 2 的电流密度，优于纯铱和Ni薄膜。通过加速降解研究，沉积的薄膜具有良好的稳定性。并在60 mV的过电位和40 mV dec -1 的Tafel斜率下实现了10 mA cm 2 的电流密度，优于纯铱和Ni薄膜。通过加速降解研究，沉积的薄膜具有良好的稳定性。