State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, P. R. China.
Nanoscale. 2018 Jul 9;10(26):12407-12412. doi: 10.1039/c8nr02854k.
Highly active and stable Pt-free electrocatalysts for hydrogen production via water splitting are of great demand for future energy systems. Herein, we report a novel hydrogen evolution reaction (HER) catalyst consisting of rhodium phosphide (Rh2P) nanoparticles as the core and N-doped carbon (NC) as the shell (Rh2P@NC). In a wide pH range, our catalyst not only possesses a small overpotential at 10 mA cm-2 (∼9 mV in 0.5 M H2SO4, ∼46 mV in 1.0 M PBS and ∼10 mV in 1.0 M KOH), but also demonstrates high stability. Importantly, all these performances are far superior to commercial Pt/C catalysts for HER. To the best of our knowledge, this is the highest HER performance reported so far in acidic and basic media. Density functional theory (DFT) calculations reveal that the introduction of phosphorus can significantly lower the proton adsorption energy of Rh/NC, thereby benefiting surface hydrogen generation. Moreover, this synthetic strategy for Rh2P@NC is also applied to other transition metal phosphides (TMPs)/nitrogen-doped carbon heterostructures (such as Ru2P@NC, Fe2P@NC, WP@NC etc.) with advanced performance toward HER and beyond.
用于水分解制氢的高效稳定无铂电催化剂对于未来的能源系统具有重要意义。在此，我们报告了一种由磷化铑（Rh2P）纳米颗粒作为核和氮掺杂碳（NC）作为壳（Rh2P@NC）组成的新型析氢反应（HER）催化剂。在很宽的 pH 值范围内，我们的催化剂不仅在 10 mA cm-2 时具有较小的过电势（在 0.5 M H2SO4 中约为 9 mV，在 1.0 M PBS 中约为 46 mV，在 1.0 M KOH 中约为 10 mV），而且还具有高稳定性。重要的是，所有这些性能都远远优于商用 Pt/C 催化剂的 HER 性能。据我们所知，这是迄今为止在酸性和碱性介质中报道的最高 HER 性能。密度泛函理论（DFT）计算表明，磷的引入可以显著降低 Rh/NC 对质子的吸附能，从而有利于表面析氢。此外，这种 Rh2P@NC 的合成策略还适用于其他过渡金属磷化物（TMPs）/氮掺杂碳异质结构（如 Ru2P@NC、Fe2P@NC、WP@NC 等），这些结构在 HER 及其他方面具有先进的性能。
