超高选择性CO_(2)光还原为乙醇的CuNi异核双原子催化剂的精准设计  

Tailoring CuNi heteronuclear diatomic catalysts:Precision in structural design for exceptionally selective CO_(2)photoreduction to ethanol

作　　者：崔恩田[1] 鲁玉莲 江吉周 Arramel 王定胜[3] 翟天佑[4] Entian Cui;Yulian Lu;Jizhou Jiang;Arramel;Dingsheng Wang;Tianyou Zhai(Key Laboratory for Advanced Technology in Environmental Protection of Jiangsu Province,Yancheng Institute of Technology,Yancheng 224051,Jiangsu,China;School of Environmental Ecology and Biological Engineering,School of Chemistry and Environmental Engineering,Key Laboratory of Green Chemical Engineering Process of Ministry of Education,Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education,Novel Catalytic Materials of Hubei Engineering Research Center,Wuhan Institute of Technology,Wuhan 430205,Hubei,China;Department of Chemistry,Tsinghua University,Beijing 100084,China;State Key Laboratory of Material Processing and Die&Mould Technology,School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,Hubei,China;Nano Center Indonesi1,Jalan Raya PUSPIPTEK,South Tangerang,Banten 15314,Indonesia)

机构地区：[1]盐城工学院江苏省新型环保重点实验室,江苏盐城224051 [2]武汉工程大学环境生态与生物工程学院,湖北新型催化材料工程研究中心,教育部磷资源开发利用工程研究中心,教育部绿色化工过程重点实验室,湖北武汉430205 [3]清华大学化学系,北京100084 [4]华中科技大学材料科学与工程学院材料加工与模具技术国家重点实验室,湖北武汉430074 [5]印尼纳米中心,印尼万丹

出　　处：《Chinese Journal of Catalysis》2024年第4期126-136,共11页催化学报（英文）

基　　金：国家自然科学基金(62004143);湖北省重点研发计划(2022BAA084)。

摘　　要：利用光催化还原技术将CO_(2)定向转化为乙醇(CO_(2)-乙醇)是解决日益严重的环境污染和能源危机的理想途径之一.然而,CO_(2)分子的高化学惰性以及C-C耦合反应的高化学能垒导致目前CO_(2)-乙醇转化反应的产率和选择性较低.因此,设计构建能够快速活化CO_(2)分子并同时促进C-C耦合的光催化材料具有重要研究意义.尽管已有研究表明,Cu+物种在促进C-C耦合方面具有一定优势,但其在催化反应过程中的不稳定性限制了其实际应用.基于上述认识,本文通过理论模拟预测发现,相比于Cu单原子,CuNi异核双原子(CuNi HDAs)不仅在CO_(2)活化及C-C耦合方面更具优势,而且能够有效锚定并固化Cu+物种.因此,本文设计了一种三步合成策略,精准地将Cu单原子锚定在(Ni,Zr)-UiO-66-NH2材料的Ni位上,合成了以CuNi HDAs为活性位点的Cu-(Ni,Zr)-UiO-66-NH2光催化材料.在可见光照射下,Cu-(Ni,Zr)-UiO-66-NH2表现出较好的催化CO_(2)-乙醇转化活性,其乙醇的产率和选择性分别达到~3218μmol·gCu^(-1)·h^(-1)和97.3%.光谱分析和密度泛函理论计算结果表明,Cu-(Ni,Zr)-UiO-66-NH2材料较好的光催化性能来源于CuNi HDAs特殊的电子结构.首先,CuNi HDAs通过CuNi-O界面化学键与吸光组分(Ni,Zr)-UiO-66-NH2相连,利用界面Cu-Ni-O键作为快速电子传输通道,CuNi HDAs能够富集到足够的光生电子用于涉及12电子的CO_(2)-乙醇转化反应,使得乙醇产率大幅提升.其次,Cu,Ni和O三种原子由于电子亲核能的差异,导致CuNi HDAs的电子分布呈现不对称性.这种不对称的电子结构能有效诱导CO_(2)分子的极化,打破其结构的对称性,从而显著降低CO_(2)分子的活化能.再次,相比于Cu单原子,CuNi HDAs对*CO中间体的吸附能力更强,这不仅增强了活性位点表面*CO中间体的覆盖度,还抑制CO的生成,为C-C耦合创造了充分条件.最后,由于Cu-Ni双活性位电子密度的差异,CuNi HDAs表面的C-C耦合反应势能较The photocatalytic reduction of CO_(2)to ethanol has attracted extensive attention,particularly for intricate C-C coupling.In this study,we propose a synthetic pathway for asymmetric CuNi heteronuclear diatoms(CuNi HDAs)by anchoring single Cu atoms on the Ni sites of(Ni,Zr)-UiO-66-NH2 to enhance C-C coupling.Cu-(Ni,Zr)-UiO-66-NH2 efficiently performs photocatalytic CO_(2)conversion with a mass-specific activity(selectivity)of 3218μmol·gCu^(-1)·h^(-1)(97.3%).Spectroscopic analyses and density functional theory calculations revealed that CuNi HDAs with an asymmetric electronic distribution facilitated the activation of CO_(2)molecules and lowered the C-C coupling barrier energy,thus promoting the formation of*OCCHO intermediates.This,in turn,led to a significant enhancement of ethanol selectivity.Furthermore,with interfacial Cu-Ni-O bonds as a rapid electron transport channel,CuNi HDAs enrich enough electrons for 12-electron CO_(2)reduction,thereby enhancing ethanol productivity.This study provides a novel strategy for designing highly selective photocatalysts for CO_(2)conversion at the atomic scale.

关 键 词：CuNi异核双原子 光催化 CO_(2)-乙醇转化 不对称电子分配 电子富集 

分 类 号：O643.36[理学—物理化学] O644.1[理学—化学] TQ223.122[化学工程—有机化工]