Electrochemical proton insertion modulates the hydrogen evolution reaction on tungsten oxides.
Electrochemical proton insertion modulates the hydrogen evolution reaction on tungsten oxides.
复制标题
电化学质子插入调节氧化钨上的析氢反应。
DOI：
10.1063/5.0082459
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
V. Augustyn
中科院分区：
文献类型：
--
作者：
Michael A. Spencer;Jenelle Fortunato;V. Augustyn
开发用于析氢反应（HER）的新型电催化剂可以减少对Pt和其他稀有金属的依赖，并实现大规模生产氢气，碳排放接近零。对材料的电催化活性的机理洞察有助于加速新的电催化剂的开发。过渡金属氧化物和硫化物等替代电催化剂材料可以发生插入反应，从而改变其性质。最近的报道表明，插入离子的存在会影响电催化活性。在这里，我们利用材料化学的方法来理解质子插入在层状氧化钨水合物（WO 3·xH 2 O，x = 1，2）的HER活性中的作用。我们合成了一系列的氧化钨水合物沿着与辛胺柱撑氧化钨（OA-WO 3）。我们使用循环伏安法来研究每种材料的电化学反应性，并进行非原位X射线衍射和拉曼光谱，以了解电化学循环过程中的体相和表面结构变化。我们发现质子插入的程度与氧化钨的HER过电位成反比关系：质子插入的缺乏导致HER过电位高。我们讨论了三种质子插入如何导致WO 3·xH 2 O中HER活性的假设：（1）质子的插入改变了WO 3·xH 2 O的电子能带结构;（2）体质子的存在影响了WO 3·xH 2 O表面位的ΔGH，ads，（3）插入的质子可能参与了WO 3·xH 2 O的HER机理。总的来说，这项工作显示了质子插入在实现钨氧化物中的高HER活性中的关键作用。
The development of new electrocatalysts for the hydrogen evolution reaction (HER) could reduce the dependence on Pt and other rare metals and enable large-scale production of hydrogen with near-zero carbon emissions. Mechanistic insight into the electrocatalytic activity of a material helps to accelerate the development of new electrocatalysts. Alternative electrocatalyst materials such as transition metal oxides and sulfides can undergo insertion reactions that change their properties. Recent reports indicate that the presence of inserted ions can influence the electrocatalytic activity. Here, we utilized a materials chemistry approach to understand the role of proton insertion in the HER activity of the layered tungsten oxide hydrates (WO3·xH2O, x = 1, 2). We synthesized a series of tungsten oxide hydrates along with an octylamine-pillared tungsten oxide (OA-WO3). We used cyclic voltammetry to study the electrochemical reactivity of each material and performed ex situ x-ray diffraction and Raman spectroscopy to understand bulk and surface structural changes during electrochemical cycling. We show an inverse relationship between the degree of proton insertion and HER overpotential in tungsten oxides: the lack of proton insertion leads to a high overpotential for the HER. We discuss three hypotheses for how proton insertion leads to the HER activity in WO3·xH2O: (1) proton insertion changes the electronic band structure of WO3·xH2O, (2) the presence of bulk protons can influence ΔGH,ads at the surface sites, and (3) the inserted protons may participate in the HER mechanism on WO3·xH2O. Overall, this work shows the critical role of proton insertion in enabling the high HER activity in tungsten oxides.