State Key Laboratory of Electroanalytical Chemistry, &Laboratory of Advanced Power Sources, Jilin Province Key Laboratory of Low Carbon Chemical Power Sources , Changchun Institute of Applied Chemistry , 5625 Renmin Street , Changchun 130022 , PR China.
State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , Changchun 130022 , PR China.
ACS Appl Mater Interfaces. 2018 Aug 8;10(31):26303-26311. doi: 10.1021/acsami.8b08068. Epub 2018 Jul 24.
Searching for cost-efficient electrocatalysts with high catalytic activity and stability for hydrogen generation by means of water electrolysis would make a great improvement on energy technologies field. Herein, we report high-performance hydrogen evolution reaction (HER) electrocatalysts based on sulfur-doped NiP nanoplate arrays grown on carbon paper (S-NiP NPA/CP). This ternary, robust, monolithic S-NiP NPA/CP exhibits remarkable performance for the HER compared to nickel phosphide and nickel sulfide catalysts. The S-NiP NPA/CP with ∼6% S presents the most promising behavior for water electrolysis applications. Specifically, it shows an onset potential of 6 mV, needing overpotentials (η) of 56 and 104 mV to attain current densities of 10 and 100 mA cm with a Tafel slope of 43.6 mV dec. The turnover frequency of 6% S-NiP NPA/CP is about 0.11 s at overpotential of 100 mV, which is ca. 10 and 40 times that of NiP NPA/CP and NiS NPA/CP, respectively. It also shows remarkable stability and durability in 0.5 M HSO solution. The results indicate that S and P tune the electronic properties mutually and produce an active catalyst phase for the HER. Furthermore, the density functional theory calculations show that S-NiP NPA/CP exhibits only 0.04 eV of hydrogen adsorption free energy(Δ G), which is more suitable than Pt (∼-0.09 eV). We propose that the S-doping not only restrains the surface oxidation and dissolution of S-NiP NPA/CP in acid solution but also reduces the Δ G. We believe that our work will provide a new strategy to design transition metal phosphide composite materials for practical applications in catalysis and energy fields.
通过水的电解来寻找高效、经济的电催化剂以提高能源技术水平将是一个巨大的进步。在此，我们报告了一种基于生长在碳纸上的硫掺杂 NiP 纳米片阵列（S-NiP NPA/CP）的高性能析氢反应（HER）电催化剂。与磷化镍和硫化镍催化剂相比，这种三元、坚固、整体的 S-NiP NPA/CP 对 HER 表现出了显著的性能。具有约 6% S 的 S-NiP NPA/CP 对水分解应用表现出最有前景的行为。具体来说，它的起始电位为 6 mV，需要超过 56 和 104 mV 的过电势才能达到 10 和 100 mA cm 的电流密度，塔菲尔斜率为 43.6 mV dec。在 100 mV 的过电势下，6% S-NiP NPA/CP 的周转频率约为 0.11 s，分别是 NiP NPA/CP 和 NiS NPA/CP 的 10 倍和 40 倍。它在 0.5 M HSO 溶液中也表现出了显著的稳定性和耐久性。结果表明，S 和 P 相互调谐电子性质，并产生了一个对 HER 有活性的催化剂相。此外，密度泛函理论计算表明，S-NiP NPA/CP 仅表现出 0.04 eV 的氢吸附自由能（Δ G），这比 Pt（约-0.09 eV）更合适。我们提出，S 掺杂不仅抑制了 S-NiP NPA/CP 在酸性溶液中的表面氧化和溶解，而且降低了 Δ G。我们相信，我们的工作将为设计用于催化和能源领域实际应用的过渡金属磷化物复合材料提供一种新策略。
