摘要
铂(Pt)基材料是酸性电解质中析氢反应活性最高、稳定性最强的电催化剂;但是它的低丰度以及昂贵的价格限制了其在质子交换膜电解水(PEMWE)技术中的应用.因此,最小化Pt的使用量并且保持其高活性成为研究热点.在本文中我们利用低温抑制成核反应冷冻干燥合成法,促使Pt组分高度分散地锚定在富含缺陷的W_(18)O_(49)纳米线上(Pt-W_(18)O_(49)),进而实现了酸性电解质中高效稳定的析氢过程.第一性原理计算证明了Pt组分与W_(18)O_(49)载体之间的强电荷相互作用可以提升析氢性能.Pt-W_(18)O_(49)催化剂中Pt用量仅为商业化20 wt%Pt/C催化剂的1/10,该催化剂在0.5 mol L^(−1)H_(2)SO_(4)电解质中达到100和1000 mA cm^(−2)电流密度时的过电位分别为116和743 mV,超过了商业化的Pt/C催化剂.该催化剂可以在500 mA cm^(−2)的高电流密度条件下持续析氢超过38 h,没有明显的性能衰减.本工作为PEMWE技术的实际应用中降低Pt用量却保持高活性开创了新的研究思路.
Platinum-based material is the most efficient and durable electrocatalyst for motivating the hydrogen evolution reaction(HER)in an acidic electrolyte;however,its low abundance and high cost limit its further application in proton-exchange membrane water electrolysis(PEMWE)technology.Therefore,minimizing the Pt amount while retaining high activity would be desirable.Herein,we use defect-rich W_(18)O_(49)nanowires to anchor well-dispersed,ultrafine Pt species(Pt-W_(18)O_(49))via a freeze-drying method to avoid aggregation,further mediating an efficient and durable HER in acidic water.Density functional theory analyses also demonstrate that the strong electronic interaction between the Pt species and W_(18)O_(49)support greatly improves the HER performance.With a 1/10 Pt loading amount of the commercial 20 wt%Pt/C,the Pt-W_(18)O_(49)catalyst requires the overpotentials of 116 and 743 mV to achieve high current densities of 100 and 1000 mA cm^(−2)in 0.5 mol L^(−1)H_(2)SO_(4),outperforming those of the 20 wt%Pt/C benchmark.More importantly,the Pt-W_(18)O_(49)catalyst can sustain a high-currentdensity HER at 500 mA cm^(−2)for more than 38 h without obvious degradation.This work paves a new avenue for synergistically reducing the Pt amount and retaining high activity for real-world PEMWE.
作者
李文欣
刘志勇
杨盛超
吴建宁
孙亮
马恩广
杨化桂
郭旭虹
Wen Xin Li;Zhi Yong Liu;Sheng Chao Yang;Jian Ning Wu;Liang Sun;En Guang Ma;Hua Gui Yang;Xuhong Guo(School of Chemistry and Chemical Engineering,Shihezi University/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan/Key Laboratory of Materials-Oriented Chemical Engineering of Xinjiang Uygur Autonomous Region/Engineering Research Center of Materials-Oriented Chemical Engineering of Xinjiang Bingtuan,Shihezi 832003,China;Key Laboratory for Ultrafine Materials of Ministry of Education,Shanghai Engineering Research Center of Hierarchical Nanomaterials,School of Materials Science and Engineering,East China University of Science and Technology,Shanghai 200237,China;State Key Laboratory of Chemical Engineering,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)
基金
the National Natural Science Foundation of China(21866028)
the Development and Innovation Program of Bingtuan(2012QY13)
the Program of Science and Technology Innovation Team in Bingtuan(2020CB006)
the Achievement Transformation and Technique Popularization Project of Shihezi University(CGZH201910).
