Reversible encapsulation tailored interfacial dynamics for boosting the water-gas shift performance  

界面动态可逆包覆促进水气变换反应性能

作　　者：Nanfang Tang Qinghao Shang Shuai Chen Yuxia Ma Qingqing Gu Lu Lin Qike Jiang Guoliang Xu Chuntian Wu Bing Yang Zhijie Wu Hui Shi Jian Liu Wenhao Luo Yu Cong 唐南方;商庆浩;陈帅;马玉霞;顾青青;林太‧露;蒋齐可;许国梁;吴春田;杨冰;吴志杰;施慧;刘健;罗文蒙;丛昱(中国科学院大连化学物理研究所,催化与新材料研究室,辽宁大连116023;中国科学院大学,北京100049;中国石油大学(北京)重质油全国重点实验室,北京102249;扬州大学化学化工学院,江苏扬州225009;中国科学院大连化学物理研究所,催化基础国家重点实验室,辽宁大连116023;萨里大学DICP-Surrey未来材料联合中心,萨里,英国;内蒙古大学化学化工学院,内蒙古自治区稀土催化重点实验室,内蒙古呼和浩特010021)

机构地区：[1]CAS Key Laboratory of Science and Technology on Applied Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,Liaoning,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]State Key Laboratory of Heavy Oil Processing and the Key Laboratory of Catalysis of CNPC,China University of Petroleum,Beijing 102249,China [4]School of Chemistry and Chemical Engineering,Yangzhou University,Yangzhou 225009,Jiangsu,China [5]State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,457 Zhongshan Road,Dalian 116023,Liaoning,China [6]DICP-Surrey Joint Centre for Future Materials,Department of Chemical and Process Engineering,University of Surrey,Guildford,Surrey,GU27XH,UK [7]Inner Mongolia Key Laboratory of Rare Earth Catalysis,College of Chemistry and Chemical Engineering Inner Mongolia University,Hohhot 010021,Inner Mongolia,China

出　　处：《Chinese Journal of Catalysis》2025年第1期394-403,共10页催化学报(英文)

基　　金：国家重点研发计划(2022YFB4300700);国家自然科学基金(21802134,22479082);中科院青年基础研究项目(YSBR-022);内蒙古大学基金(10000-23112101/081);内蒙古青年科技英才基金(NJYT24019)。

摘　　要：Revealing the structure evolution of interfacial active species during a dynamic catalytic process is a challenging but pivotal issue for the rational design of high-performance catalysts.Here,we successfully prepare sub-nanometric Pt clusters(~0.8 nm)encapsulated within the defects of CeO_(2)nanorods via an in-situ defect engineering methodology.The as-prepared Pt@d-CeO_(2)catalyst significantly boosts the activity and stability in the water-gas shift(WGS)reaction compared to other analogs.Based on controlled experiments and complementary(in-situ)spectroscopic studies,a reversible encapsulation induced by active site transformation between the Pt^(2+)-terminal hydroxyl and Pt^(δ+)-O vacancy species at the interface is revealed,which enables to evoke the enhanced performance.Our findings not only offer practical guidance for the design of high-efficiency catalysts but also bring a new understanding of the exceptional performance of WGS in a holistic view,which shows a great application potential in materials and catalysis.水气变换反应(WGS)是重要的制氢和CO脱除过程,广泛应用于能源相关领域。前期研究表明,模型催化剂上金属-载体界面在WGS反应决速步-水活化解离过程中起着重要作用;金属键合的羟基物种直接参与了水活化过程,可有效提高WGS反应效率.然而,如何精准制备富含金属-氧化物界面活性位的高性能WGS反应催化剂,以及原位追踪反应过程中活性位、关键活性物种的动态演化仍是一项重要挑战.本文利用“缺陷工程”策略通过两步水热法成功将Pt团簇(~0.8nm)包覆在富含缺陷位CeO_(2)纳米棒中,获得了Pt@d-CeO_(2)催化剂.将Pt@d-CeO_(2)用于WGS反应中,在极高空速(GHSV=150000 h^(-1))下,300℃时CO转化率为86%,350℃时达到平衡转化率(95%).转化频率值在350℃时高达12.27 s^(-1),比已报道的相近反应条件下同类催化剂高一个数量级.催化剂具有良好的稳定性,经100h反应,CO转化率未发现明显下降.像差校正透射电镜结果表明,Pt团簇以0.6-1nm尺度分散在氧化上,且被氧化铈薄层包覆.能量散射谱、电子能量损失谱、X射线光电子能谱(XPS)和原位透射模式傅里叶变换红外光谱(TM-FT-IR)结果均证实了Pt-CeO_(2)的界面包覆特性。程序升温表面脱附结果初步表明,Pt@d-CeO_(2)催化剂上WGS反应总体历程是CO先在Pt-CeO_(2)界面处反应生成CO_(2),然后HO解离生成H_(2)CO-程序升温还原、原位TM-FT-IR和原位近环境压力XPS结果表明,Pt-CeO_(2)包覆界面为本征活性位,界面处的端-OH为关键活性物种.利用一系列原位表征手段实时追踪界面活性位和端-OH在反应过程中的动态演化,进而提出Pt@d-CeO_(2)催化剂上WGS反应的详细反应历程:依据一系列原位表征结果提出Pt@d-CeO_(2)催化剂上WGS反应的详细反应历程:首先,CO与Pt-CeO_(2)包覆界面处的端-OH反应生成活性中间物种COOH,继而分解成CO_(2)和H_(2)CeO_(2)包覆的Pt团簇部分暴露并产生新的活性氧空位;然后,H

关 键 词：Interfacial dynamics HYDROXYLS Water-gas shiftreaction In-situspectroscopy 

分 类 号：O64[理学—物理化学]