Modulation of the electronic structure of CoP active sites by Er-doping for nitrite reduction for ammonia electrosynthesis  

Er掺杂调控CoP活性位点的电子结构促进亚硝酸盐电还原合成氨

作　　者：Donglin Zhao Keyu Zhou Li Zhan Guangyin Fan Yan Long Shuyan Song 赵东林;周科宇;詹丽;樊光银;龙艳;宋术岩(四川师范大学化学与材料科学学院,四川成都610068;中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,吉林长春130022)

机构地区：[1]College of Chemistry and Materials Science,Sichuan Normal University,Chengdu,610068,Sichuan,China [2]State Key Laboratory of Rare Earth Resource Utilization,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,Jilin,China

出　　处：《Chinese Journal of Catalysis》2025年第3期299-310,共12页催化学报(英文)

摘　　要：The electrochemical conversion of toxic nitrite(NO_(2)-)is a promising approach for the simultaneous removal of nitrogen contaminants and synthesis of ammonia(NH_(3)).In this study,we present the Er-doping-induced electronic modulation of CoP integrated with nitrogen-doped carbon(CN)nanosheets supported on a titanium mesh(Er-CoP@NC/TM)for the electrocatalytic NO_(2)-reduction reaction(eNO_(2)-RR)for NH_(3)synthesis.The catalyst demonstrates a high Faraday efficiency of 97.08±2.22%and a high yield of 2087.60±17.10μmol h^(-1)cm^(-2)for NH_(3)production.Characterization and theoretical calculations revealed that Er-doping facilitated the electronic modulation of CoP in Er-CoP@NC/TM,which regulated the adsorption behaviors of intermediates and was the rate-limiting step for the eNO_(2)-RR,thereby enhancing the electrocatalytic performance.Quenching experiments and electron paramagnetic resonance tests suggest that both direct electrocatalytic reduction by active hydrogen and electron transfer are critical for the eNO_(2)-RR for NH_(3)synthesis.Furthermore,Er-CoP@NC/TM exhibited high performance across a wide range of NO_(2)-concentrations(0.05-0.1 mol L-1)and pH values(4-13).In addition,the catalyst demonstrated strong resistance to anions and a long cycle life in simulated wastewater environments.This study offers a powerful approach for the remediation of NO_(2)-wastewater and recovery of valuable inorganic compounds.氨(NH_(3))作为一种重要的无机化工原料,广泛应用于农业、工业和储能等领域.目前,工业上NH_(3)的生产方法是传统的哈伯-博施工艺.该工艺反应条件苛刻,能量耗损高,并且会同时产生大量的温室气体,给生态环境带来极大的危害.电催化亚硝酸盐还原(eNO_(2)^(-)RR)合成NH_(3)是一种高效、可控且可持续的NH_(3)合成替代途径,有望突破传统NH_(3)合成工艺的限制.此外,废水中广泛存在的亚硝酸盐(NO_(2)^(-))是一种常见的致癌物质,严重危害环境和人类健康.然而,电催化NO_(2)^(-)还原合成NH_(3)是一个六电子转移过程,可能产生多种含氮中间产物,从而影响产物的选择性.因此,为了解决能源和环境问题,合理构建简单、稳定且高效的电催化剂至关重要.这不仅能实现NH_(3)的绿色合成,还能去除废水中有毒的NO_(2)^(-).本文开发了一种独特而有效的以稀土金属元素铒(Er)为介导的价电子和表面微环境调控方法.带有孤对电子的含氮有机配体与带正电荷的Er和金属钴(Co)离子之间的强配位,确保了通过热解合成的样品中Er和Co位点的强烈耦合.随后,通过磷化反应在钛网基底上合成了Er掺杂的磷化钴复合的碳氮纳米片(Er-CoP@NC/TM)催化剂.值得注意的是,Er的引入调控了Co位点的价电子分布,使Er-CoP@NC/TM催化剂表现出较好的电催化合成NH_(3)性能.在工作电压为-0.8 V vs.RHE时,Er-CoP@NC/TM催化剂获得的最大氨产率达到2087.60±17.10μmol h^(-1)cm^(-2);在工作电压为-0.4V vs.RHE时,Er-CoP@NC/TM催化剂的最大法拉第效率为97.08±2.22%,其催化活性远大于原始的磷化钴复合的碳氮纳米片(CoP@NC/TM)催化剂.此外,Er-CoP@NC/TM催化剂在较宽的NO_(2)^(-)浓度(0.05-0.1 mol L^(-1))和pH值(4-13)范围内也表现出卓越的电催化合成NH_(3)性能.同时,Er-CoP@NC/TM催化剂在模拟废水环境中表现出较强的抗阴离子干扰能力和较长的循环寿命.此外,淬灭实验和电子�

关 键 词：ELECTROCATALYSIS Nitrite reduction Ammonia production Cobalt phosphide Er-doping 

分 类 号：O643.3[理学—物理化学]