{"title":"Cu Nanoclusters and Rh Single-Atom-Modified N-Doped Carbon for Electroreduction of Nitrate to Ammonia.","authors":"Wenhan Dai,Yahan Fang,Junfeng Huang,Zhongwei Wang,Jian Li,Mudong Tu,Huijiao Wang,Jun Yang,Cailing Xu,Hua Li","doi":"10.1021/acs.inorgchem.5c03508","DOIUrl":null,"url":null,"abstract":"To tackle the pressing issue of nitrate (NO3-) pollution in wastewater and simultaneously convert it into ammonia (NH3), Cu nanocluster-modified Rhodium (Rh) single atoms anchored on N-doped carbon were synthesized via pyrolysis of a zeolitic imidazolate framework-8 (ZIF-8) precursor and applied to the electrochemical reduction of nitrate at a low concentration. Structural characterizations (X-ray powder diffractometer (XRD), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS)) confirmed the coexistence of Rh single atoms and Cu nanoclusters as well as their strong electronic interactions. Mechanistic investigations revealed that Rh sites enhanced *H generation via water dissociation and promoted NO3- adsorption, thereby facilitating *H transfer and subsequent hydrogenation steps. As a result, the optimized Cu97.5Rh2.5/NC catalyst exhibited outstanding NO3-RR performance, with a Faradaic efficiency (FE) of 84.53%, an NH3 yield rate of 1252.22 μg·h-1 mgcat-1 at -1.0 V vs reversible hydrogen electrode (RHE), an NH3 selectivity of 89.13% at -1.0 V vs RHE, and a NO3- conversion rate of 93.34% at -1.1 V vs RHE. This work presents a rational design for atom-economical catalysts, enabling sustainable NH3 electrosynthesis from nitrate-laden wastewater and reducing effluent NO3--N to meet World Health Organization (WHO) drinking water standards.","PeriodicalId":40,"journal":{"name":"Inorganic Chemistry","volume":"93 1","pages":""},"PeriodicalIF":4.7000,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Inorganic Chemistry","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1021/acs.inorgchem.5c03508","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
To tackle the pressing issue of nitrate (NO3-) pollution in wastewater and simultaneously convert it into ammonia (NH3), Cu nanocluster-modified Rhodium (Rh) single atoms anchored on N-doped carbon were synthesized via pyrolysis of a zeolitic imidazolate framework-8 (ZIF-8) precursor and applied to the electrochemical reduction of nitrate at a low concentration. Structural characterizations (X-ray powder diffractometer (XRD), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and X-ray photoelectron spectroscopy (XPS)) confirmed the coexistence of Rh single atoms and Cu nanoclusters as well as their strong electronic interactions. Mechanistic investigations revealed that Rh sites enhanced *H generation via water dissociation and promoted NO3- adsorption, thereby facilitating *H transfer and subsequent hydrogenation steps. As a result, the optimized Cu97.5Rh2.5/NC catalyst exhibited outstanding NO3-RR performance, with a Faradaic efficiency (FE) of 84.53%, an NH3 yield rate of 1252.22 μg·h-1 mgcat-1 at -1.0 V vs reversible hydrogen electrode (RHE), an NH3 selectivity of 89.13% at -1.0 V vs RHE, and a NO3- conversion rate of 93.34% at -1.1 V vs RHE. This work presents a rational design for atom-economical catalysts, enabling sustainable NH3 electrosynthesis from nitrate-laden wastewater and reducing effluent NO3--N to meet World Health Organization (WHO) drinking water standards.
为了解决废水中硝酸盐(NO3-)污染的紧迫问题,同时将其转化为氨(NH3),通过沸石咪唑酸框架-8 (ZIF-8)前驱体热解合成了锚定在n掺杂碳上的Cu纳米簇修饰铑(Rh)单原子,并将其应用于低浓度硝酸盐的电化学还原。结构表征(x射线粉末衍射仪(XRD)、高角环形暗场扫描透射电子显微镜(HAADF-STEM)和x射线光电子能谱(XPS))证实了Rh单原子和Cu纳米团簇的共存以及它们之间的强电子相互作用。机理研究表明,Rh位点通过水解离促进*H生成,促进NO3-吸附,从而促进*H转移和随后的加氢步骤。结果表明,优化后的Cu97.5Rh2.5/NC催化剂表现出优异的NO3- rr性能,在-1.0 V vs可逆氢电极(RHE)条件下,Faradaic效率(FE)为84.53%,NH3产率为1252.22 μg·h-1 mgcat-1,在-1.0 V vs RHE条件下,NH3选择性为89.13%,在-1.1 V vs RHE条件下,NO3-转化率为93.34%。本研究提出了一种合理的原子经济型催化剂设计,使含硝酸盐废水可持续电合成NH3,并降低出水NO3——N,以满足世界卫生组织(WHO)的饮用水标准。
期刊介绍:
Inorganic Chemistry publishes fundamental studies in all phases of inorganic chemistry. Coverage includes experimental and theoretical reports on quantitative studies of structure and thermodynamics, kinetics, mechanisms of inorganic reactions, bioinorganic chemistry, and relevant aspects of organometallic chemistry, solid-state phenomena, and chemical bonding theory. Emphasis is placed on the synthesis, structure, thermodynamics, reactivity, spectroscopy, and bonding properties of significant new and known compounds.