Electrocatalytic Hydrogen Evolution using a Nickel-based Calixpyrrole Complex: Controlling the Secondary Coordination Sphere on an Electrode Surface.
Electrocatalytic Hydrogen Evolution using a Nickel-based Calixpyrrole Complex: Controlling the Secondary Coordination Sphere on an Electrode Surface.
复制标题
使用镍基杯吡咯配合物进行电催化析氢：控制电极表面上的二次配位球。
DOI：
10.1002/chem.202301920
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Sues,PeterE
中科院分区：
文献类型：
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作者：
Trowbridge,Logan;Averkiev,Boris;Sues,PeterE
从均相催化剂中提取设计元素，在电极表面构建明确的活性位点，是开发下一代能量转换反应电催化剂的一种有前途的方法。此外，如果控制电极微环境的功能可以集成到这些活性位点中，则将特别有吸引力。在这种情况下，报道了具有侧胺基的正方形平面镍杯吡咯络合物Ni（DPMDA）（DPMDA= 2，2 ′-（（二苯基亚甲基）双（1H-吡咯-5，2-二基））双（亚甲烷基））双（亚氮烷基））二苯胺），其使用四氟硼酸苯铵作为质子源形成非均相析氢催化剂。经重氮化的Ni（DPMDA）催化剂令人惊讶地稳定，并显示出快速的反应动力学，转换频率（TOF）高达25，900 s-1或366，000 s-1cm-2。 动力学同位素效应（KIE）研究显示KIE为5.7，该数据与塔菲尔斜率分析相结合，表明涉及侧胺基的质子耦合电子转移（PCET）过程是限速的。虽然观察到蒂尼（DPMDA）催化剂的外层还原的证据，但假设对由侧基胺提供的二级配位层的控制促进了这种高TOF并实现了PCET机制。本文报道的结果提供了深入了解非均相催化剂的设计和方法，用于控制电极表面上的二次配位球。
Incorporating design elements from homogeneous catalysts to construct well defined active sites on electrode surfaces is a promising approach for developing next generation electrocatalysts for energy conversion reactions. Furthermore, if functionalities that control the electrode microenvironment could be integrated into these active sites it would be particularly appealing. In this context, a square planar nickel calixpyrrole complex,Ni(DPMDA)(DPMDA=2,2′‐((diphenylmethylene)bis(1H‐pyrrole‐5,2‐diyl))bis(methaneylylidene))bis(azaneylylidene))dianiline) with pendant amine groups is reported that forms a heterogeneous hydrogen evolution catalyst using anilinium tetrafluoroborate as the proton source. The supportedNi(DPMDA)catalyst was surprisingly stable and displayed fast reaction kinetics with turnover frequencies (TOF) up to 25,900 s−1or 366,000 s−1cm−2. Kinetic isotope effect (KIE) studies revealed a KIE of 5.7, and this data, combined with Tafel slope analysis, suggested that a proton‐coupled electron transfer (PCET) process involving the pendant amine groups was rate‐limiting. While evidence of an outer‐sphere reduction of theNi(DPMDA)catalyst was observed, it is hypothesized that the control over the secondary coordination sphere provided by the pendant amines facilitated such high TOFs and enabled the PCET mechanism. The results reported herein provide insight into heterogeneous catalyst design and approaches for controlling the secondary coordination sphere on electrode surfaces.