High-Efficient, Stable Electrocatalytic Hydrogen Evolution in Acid Media by Amorphous FexP Coating Fe2N Supported on Reduced Graphene Oxide
High-Efficient, Stable Electrocatalytic Hydrogen Evolution in Acid Media by Amorphous FexP Coating Fe2N Supported on Reduced Graphene Oxide
复制标题
还原氧化石墨烯负载非晶态 FexP 涂层 Fe2N 在酸性介质中高效、稳定电催化析氢
DOI：
10.1002/smll.201801717
复制
发表时间：
2018
期刊：
影响因子：
13.3
通讯作者：
Fu Honggang
中科院分区：
文献类型：
--
作者：
Yu Peng;Wang Lei;Xie Ying;Tian Chungui;Sun Fanfei;Ma Jingyuan;Tong Miaomiao;Zhou Wei;Li Jinghong;Fu Honggang
开发高效、耐用的非铂催化剂用于酸性介质中析氢反应（HER）是迫切需要的。氮化铁因其成本效益而成为一种很有前途的催化剂，但必须提高相应的酸性稳定性。本文设计并合成了磷修饰Fe2N和还原氧化石墨烯（P - Fe2N/rGO）复合材料。X射线光电子能谱和X射线吸收精细结构（XAFS）表明，Fe2N纳米颗粒表面包覆了一层薄薄的无定形磷化铁，这可能是Fe2N纳米颗粒在酸性介质中具有良好耐化学腐蚀性能的原因。同时，XAFS结果表明，P‐修饰可以调节铁原子的电子态和配位环境，从而显著提高P‐Fe2N/rGO的电催化活性。密度泛函理论计算表明，P - Fe2N/rGO催化剂中P -连接的N原子和Fe原子是H*吸附的主要活性位点。P - Fe2N/rGO的氢结合自由能|ΔGH*|值接近于零，表明HER动力学中Volmer和Heyrovsky/Tafel步骤之间存在良好的平衡。正如预期的那样，P‐Fe2N/rGO催化剂可以实现22.4 mV的低η起始值，48.7 mV dec−1的小Tafel图，以及在酸性电解质中显着的HER稳定性。
Development of efficient and durable non‐Pt catalysts for hydrogen evolution reaction (HER) in acid media is highly desirable. Iron nitride has emerged as a promising catalyst for its cost‐effective nature, but the corresponding acidic stability must be promoted. Herein, phosphorus‐decorated Fe2N and reduced graphene oxide (P‐Fe2N/rGO) composite are designed and synthesized. X‐ray photoelectron spectroscopy and X‐ray absorption fine structure (XAFS) show that a thin layer amorphous iron phosphide is coated on the surface of Fe2N nanoparticles, which could be responsible for the well resistance of chemical corrosion in acidic media. Meanwhile, the P‐decoration could tune the electronic state and coordination environment of iron atom as evidenced by XAFS, resulting in dramatically enhanced electrocatalytic activity of P‐Fe2N/rGO. Density functional theory calculations reveal that both the P‐connected N atoms and the Fe atoms in P‐Fe2N/rGO catalyst are the main active sites for H* adsorption. The hydrogen‐binding free energy |ΔGH*| value is close to zero for P‐Fe2N/rGO, suggesting a good balance between the Volmer and Heyrovsky/Tafel steps in HER kinetics. As expected, P‐Fe2N/rGO catalyst could achieve a low ηonsetof 22.4 mV, a small Tafel plot of 48.7 mV dec−1, and remarkable stability for HER in acid electrolyte.