Yuanqi Liu, Qiang Gao, Lei Shi, Joseph Kearney, Xue Han, Zhenhua Xie, Maoyu Wang, Hua Zhou and Huiyuan Zhu
{"title":"Single-atom molybdenum doping induces nickel oxide-to-hydroxide transformation for enhanced alkaline hydrogen evolution†","authors":"Yuanqi Liu, Qiang Gao, Lei Shi, Joseph Kearney, Xue Han, Zhenhua Xie, Maoyu Wang, Hua Zhou and Huiyuan Zhu","doi":"10.1039/D5NH00302D","DOIUrl":null,"url":null,"abstract":"<p >NiMoO<small><sub><em>x</em></sub></small> compounds are widely regarded as among the most efficient non-noble metal catalysts for the hydrogen evolution reaction (HER). Nevertheless, understanding the structural evolution under <em>in situ</em> conditions and further enhancing their performance remain key challenges. Herein, we report that single-atom Mo doping in NiO significantly enhances its HER activity, reducing the overpotential to 131 mV at 10 mA cm<small><sup>−2</sup></small> compared to undoped NiO. <em>In situ</em> X-ray absorption spectroscopy and Raman spectroscopy reveal that under catalytic conditions, Mo single atoms remain structurally stable, while Ni<small><sup>2+</sup></small> species in NiO are converted to Ni(OH)<small><sub>2</sub></small> in alkaline media under the applied working potential for HER. Notably, this transformation is absent in undoped NiO, indicating that Mo doping promotes the formation of active Ni(OH)<small><sub>2</sub></small> sites, which, in turn, accelerate the rate-limiting water dissociation step. These findings provide critical mechanistic insights into the structural evolution of NiMoO<small><sub><em>x</em></sub></small> during alkaline HER and highlight the importance of <em>in situ</em> studies in the development of highly efficient catalysts.</p>","PeriodicalId":93,"journal":{"name":"Nanoscale Horizons","volume":" 9","pages":" 2037-2044"},"PeriodicalIF":6.6000,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/nh/d5nh00302d?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nanoscale Horizons","FirstCategoryId":"88","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/nh/d5nh00302d","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
NiMoOx compounds are widely regarded as among the most efficient non-noble metal catalysts for the hydrogen evolution reaction (HER). Nevertheless, understanding the structural evolution under in situ conditions and further enhancing their performance remain key challenges. Herein, we report that single-atom Mo doping in NiO significantly enhances its HER activity, reducing the overpotential to 131 mV at 10 mA cm−2 compared to undoped NiO. In situ X-ray absorption spectroscopy and Raman spectroscopy reveal that under catalytic conditions, Mo single atoms remain structurally stable, while Ni2+ species in NiO are converted to Ni(OH)2 in alkaline media under the applied working potential for HER. Notably, this transformation is absent in undoped NiO, indicating that Mo doping promotes the formation of active Ni(OH)2 sites, which, in turn, accelerate the rate-limiting water dissociation step. These findings provide critical mechanistic insights into the structural evolution of NiMoOx during alkaline HER and highlight the importance of in situ studies in the development of highly efficient catalysts.
NiMoOx化合物被广泛认为是析氢反应(HER)最有效的非贵金属催化剂之一。然而,了解原位条件下的结构演变并进一步提高其性能仍然是关键的挑战。本文中,我们报道了NiO中单原子Mo掺杂显著提高了其HER活性,与未掺杂的NiO相比,在10 mA cm-2下将过电位降至131 mV。原位x射线吸收光谱和拉曼光谱显示,在催化条件下,Mo单原子保持结构稳定,而NiO中的Ni2+在碱性介质中在HER的工作电位下转化为Ni(OH)2。值得注意的是,在未掺杂的NiO中没有这种转变,这表明Mo掺杂促进了活性Ni(OH)2位点的形成,从而加速了限速水解离步骤。这些发现为NiMoOx在碱性HER过程中的结构演变提供了关键的机制见解,并强调了原位研究在高效催化剂开发中的重要性。
期刊介绍:
Nanoscale Horizons stands out as a premier journal for publishing exceptionally high-quality and innovative nanoscience and nanotechnology. The emphasis lies on original research that introduces a new concept or a novel perspective (a conceptual advance), prioritizing this over reporting technological improvements. Nevertheless, outstanding articles showcasing truly groundbreaking developments, including record-breaking performance, may also find a place in the journal. Published work must be of substantial general interest to our broad and diverse readership across the nanoscience and nanotechnology community.