模板稳定化的氧化镍析氧催化剂。
Template-stabilized oxidic nickel oxygen evolution catalysts.
机构信息
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138.
Chemical Sciences and Engineering Division, Argonne National laboratory, Lemont, IL 60439.
出版信息
Proc Natl Acad Sci U S A. 2020 Jul 14;117(28):16187-16192. doi: 10.1073/pnas.2001529117. Epub 2020 Jul 7.
Earth-abundant oxygen evolution catalysts (OECs) with extended stability in acid can be constructed by embedding active sites within an acid-stable metal-oxide framework. Here, we report stable NiPbO films that are able to perform oxygen evolution reaction (OER) catalysis for extended periods of operation (>20 h) in acidic solutions of pH 2.5; conversely, native NiO catalyst films dissolve immediately. In situ X-ray absorption spectroscopy and ex situ X-ray photoelectron spectroscopy reveal that PbO is unperturbed after addition of Ni and/or Fe into the lattice, which serves as an acid-stable, conductive framework for embedded OER active centers. The ability to perform OER in acid allows the mechanism of Fe doping on Ni catalysts to be further probed. Catalyst activity with Fe doping of oxidic Ni OEC under acid conditions, as compared to neutral or basic conditions, supports the contention that role of Fe in enhancing catalytic activity in Ni oxide catalysts arises from its Lewis acid properties.
通过将活性位点嵌入在酸稳定的金属氧化物骨架中，可以构建在酸性条件下具有延长稳定性的丰富地球氧析出催化剂（OEC）。在这里，我们报道了稳定的 NiPbO 薄膜，其能够在 pH 值为 2.5 的酸性溶液中进行长时间的氧析出反应（OER）催化 (>20 h)；相比之下，天然 NiO 催化剂薄膜会立即溶解。原位 X 射线吸收光谱和非原位 X 射线光电子能谱揭示，在晶格中添加 Ni 和/或 Fe 后，PbO 没有受到干扰，其充当了嵌入 OER 活性中心的酸稳定、导电骨架。在酸性条件下进行 OER 的能力进一步探究了 Fe 掺杂 Ni 催化剂的机制。与中性或碱性条件相比，在酸性条件下 Fe 掺杂氧化 Ni OEC 的催化剂活性支持这样的论点，即在 Ni 氧化物催化剂中增强催化活性的 Fe 的作用源自其路易斯酸性质。
Zotero 插件