Electrocatalytic hydrogenation of phenol on platinum-cobalt alloys
Electrocatalytic hydrogenation of phenol on platinum-cobalt alloys
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DOI：
10.1016/j.jcat.2024.115331
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发表时间：
2024-01
影响因子：
7.3
通讯作者：
James Akinola;Isaiah Barth;B. Goldsmith;Nirala Singh
中科院分区：
文献类型：
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作者：
James Akinola;Isaiah Barth;B. Goldsmith;Nirala Singh
在这里，我们调查铂钴合金，以确定控制苯酚的电催化加氢（ECH）和竞争析氢反应（HER）的催化剂性能。我们进行ECH的苯酚PtxCoy纳米粒子，并证明在一定的电位下PtxCoy合金比Pt更活跃。电化学测量、密度泛函理论（DFT）计算和动力学模型的结合表明，由于PtxCoy上的反应过程比Pt上的反应过程吸热更快，所以用电化学测量、密度泛函理论（DFT）计算和动力学模型的结合表明，对于苯酚ECH来说，ΔGHis并不是一个足够的描述符.通过DFT模拟，我们发现加氢活化能与Co含量之间的关系强烈依赖于催化剂表面是Pt皮还是同时含有Pt和Co原子。通过将计算出的活化能谱纳入动力学模型中，我们描述了实验ECH动力学的苯酚PtxCoyalloys作为施加的电位和Co组合物的函数的定性趋势。
Here we investigate platinum-cobalt alloys to determine catalyst properties that control electrocatalytic hydrogenation (ECH) of phenol and the competing hydrogen evolution reaction (HER). We perform ECH of phenol on PtxCoynanoparticles and demonstrate that under certain potentials PtxCoyalloys are more active than Pt. However, the ECH activity does not correlate directly with the hydrogen adsorption energy (ΔGH), unlike what we find for HER. Combined electrochemical measurements, density functional theory (DFT) calculations, and kinetic modeling reveal that ΔGHis an insufficient descriptor for phenol ECH because the activation enthalpies for hydrogenation elementary steps scale more closely with their reaction enthalpies, which are more endothermic on PtxCoycompared to Pt. Through DFT modeling we show the relationship between hydrogenation activation enthalpies and Co content depends strongly on whether the catalyst surface is a Pt skin or contains both Pt and Co atoms. By incorporating the computed activation enthalpies into a kinetic model, we describe the qualitative trends in experimental ECH kinetics of phenol on PtxCoyalloys as a function of applied potential and Co composition.