High-density Au-OV synergistic sites boost tandem photocatalysis for CO_(2) hydrogenation to CH_(3)OH  

高密度Au-Ov协同位点促进串联光催化CO_(2)加氢制CH_(3)OH

作　　者：Xingjuan Li Yuhao Guo Qinhui Guan Xiao Li Lulu Zhang Weiguang Ran Na Li Tingjiang Yan 李兴娟;郭昱昊;管勤辉;李晓;张璐璐;冉维广;李娜;颜廷江(曲阜师范大学化学与化工学院,山东省高校催化转化与清洁能源重点实验室,山东曲阜273165;陕西科技大学化学与化工学院,陕西西安710021)

机构地区：[1]Key Laboratory of Catalytic Conversion and Clean Energy in Universities of Shandong Province,School of Chemistry and Chemical Engineering,Qufu Normal University,Qufu 273165,Shandong,China [2]College of Chemistry and Chemical Engineering,Shaanxi University of Science and Technology,Xi’an 710021,Shannxi,China

出　　处：《Chinese Journal of Catalysis》2025年第2期303-314,共12页催化学报(英文)

基　　金：国家自然科学基金(22172086,22105117);山东省泰山学者人才项目(tsqn202103064);山东省自然科学重大基础研究项目(ZR2021ZD06);山东省自然科学基金项目(ZR2021QB041,ZR2020QE053).

摘　　要：The production of renewable methanol(CH_(3)OH)via the photocatalytic hydrogenation of CO_(2) is an ideal method to ameliorate energy shortages and mitigate CO_(2) emissions:however,the highly selective synthesis of methanol at atmospheric pressure remains challenging owing to the competing reverse water-gas shift(RWGS)reaction.Herein,we present a novel approach for the synthesis of CH_(3)OH via photocatalytic CO_(2) hydrogenation using a catalyst featuring highly dispersed Au nanoparticles loaded on oxygen vacancy(OV)-rich molybdenum dioxide(MoO_(2)),resulting in a remarkable selectivity of 43.78%.The active sites in the Au/MoO_(2) catalyst are high-density Au-oxygen vacancies,which synergistically promote the tandem methanol synthesis via an initial RWGS reaction and subsequent CO hydrogenation.This work provides comprehensive insights into the design of metal-vacancy synergistic sites for the highly selective photocatalytic hydrogenation of CO_(2) to CH_(3)OH.近年来,CO_(2)大量排放带来了一系列环境问题,资源化利用CO_(2)来开展绿色减碳排放是一项紧迫任务。利用光催化将CO_(2)转化为有价值的化学物质,如一氧化碳(CO)、甲烷(CH_(4))、甲醇(CH_(3)OH),甚至C_(2-)产品,是解决能源短缺和减少CO_(2)排放的理想途径。然而,传统的单一半导体催化剂通常仅有单一活性位点,存在光生电子-空穴对的快速复合和反应产物选择性差等问题.因此,为了高效、高选择性地实现光催化CO_(2)还原反应,有必要设计一种具有多个活性位点协同作用的催化剂。本文首先利用钼粉、乙醇和H2O,为原料在溶剂热条件下合成出三氧化钼(MoO_(3)),然后将其在还原气氛中缎烧处理制备出富含氧空位的氧化钼(MoO_(3)和MoO_(2)),进一步通过光沉积技术在三种氧化钼表面负载金纳米颗粒,最终得到了用于光催化CO_(2)加氢反应的催化剂(Au/MoO_(3),Au/MoO和Au/MoO_(2)).光催化实验结果表明,Au/MoO_(2)催化剂在光催化CO_(2)加氢反应中产生的CH_(3)OH产物的产率呈现递增的趋势,CH_(3)OH的生成来自于另一产物COCO_(2)加氢;串联催化;甲醇;Au/MoO_(2);光催化的加氢反应.X射线粉末衍射、扫描电镜和高分辨透射电镜等结果表明,相比MoO_(3)和MoO_(3-x)氧空位浓度最高的MoO_(2)更利于Au纳米颗粒的锚定和均匀负载,金属-氧化物界面作用更强光电流响应和阻抗图谱等结果表明,Au/MoO_(2)催化剂界面形成的肖特基结,显著提高了光生载流子的传输和分离效率.CO_(2)和H_(2)程序升温脱附结果表明,Au/MoO_(2)催化剂上的CO_(2)和H_(2)吸附活化能力强于Au/MoO_(3)和Au/MoO_(3-x)催化剂。原位红外实验表明,Au/MoO_(2)催化剂上CO_(2)经HCOO^(*)和HCO_(3)^(+)中间体加氢生成甲醇,且Au/MoO_(2)催化剂上的HCOO^(*)和HCO_(2)物种浓度显著高于其它催化剂。由于MoO_(2)具有丰富的氧空位,更容易吸附和活化CO_(2)分子;Au位点的存在促进了H_(2)解离并增�

关 键 词：CO_(2)hydrogenation Tandem catalysis Methanol Au/Mo0_(2) PHOTOCATALYSIS 

分 类 号：O643.32[理学—物理化学]