Size-dependent strong metal-support interaction modulation of Pt/CoFe_(2)O_(4) catalysts  

尺寸依赖的金属载体相互作用调控Pt/CoFe_(2)O_(4)催化反应性能

作　　者：Yangyang Li Jingyi Yang Botao Qiao Tao Zhang 李阳阳;杨静怡;乔波涛;张涛(中国科学院大连化学物理研究所,中国科学院应用催化科学技术重点实验室,辽宁大连116023;中国科学院大学,北京100049;德国马普学会弗里茨·哈伯研究所,德国柏林;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)

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]Fritz Haber Institute of the Max Planck Society,Berlin 14195,Germany [4]State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,Liaoning,China

出　　处：《Chinese Journal of Catalysis》2025年第2期292-302,共11页催化学报(英文)

基　　金：国家重点研发计划(2021YFA1500503);国家自然科学基金单原子催化基础研究中心(22388102);国家自然科学基金联合基金(U23A20110)。

摘　　要：Supported metal catalysts are the backbone of heterogeneous catalysis,playing a crucial role in the modern chemical industry.Metal-support interactions(MSIs)are known important in determining the catalytic performance of supported metal catalysts.This is particularly true for single-atom catalysts(SACs)and pseudo-single-atom catalysts(pseudo-SACs),where all metal atoms are dispersed on,and interact directly with the support.Consequently,the MSI of SACs and pseudo-SACs are theoretically more sensitive to modulation compared to that of traditional nanoparticle catalysts.In this work,we experimentally demonstrated this hypothesis by an observed size-dependent MSI modulation.We fabricated CoFe_(2)O_(4) supported Pt pseudo-SACs and nanoparticle catalysts,followed by a straightforward water treatment process.It was found that the covalent strong metal-support interaction(CMSI)in pseudo-SACs can be weakened,leading to a significant activity improvement in methane combustion reaction.This finding aligns with our recent observation of CoFe_(2)O_(4) supported Pt SACs.By contrast,the MSI in Pt nanoparticle catalyst was barely affected by the water treatment,giving rise to almost unchanged catalytic performance.This work highlights the critical role of metal size in determining the MSI modulation,offering a novel strategy for tuning the catalytic performance of SACs and pseudo-SACs by fine-tuning their MSIs.负载型金属催化剂是应用最为广泛的多相催化剂之一,在现代化学工业中起着举足轻重的作用,依据被负载金属的尺寸,负载型金属催化剂可大致划分为三类:(1)纳米催化剂(NPCs),其金属尺寸范围从几纳米至数百纳米;(2)单原子催化剂(SACs),这是一类新兴催化剂,其特点是金属以单个原子形式分散在载体表面;(3)准单原子催化剂(pseudo-SACs),金属中心的尺寸介于单原子和纳米颗粒之间,一般由数个至数十个原子组成,通常以单层形式分散于载体表面,也被称为“原子级分散催化剂(ADCs)"或“全暴露的团簇催化剂(FECC)"。一方面,Pseudo-SACs具有SACs的高原子利用率的优点;另一方面,pseudo-SACs的活性位点由多个原子组成,使其更适用于需要多原子协同的复杂反应,因而是SACs和传统NPCs的有益补充.众所周知,金属-载体相互作用(MSI)在决定负载型金属催化剂的催化性能方面起着非常重要的作用,不仅影响负载金属颗粒的分散度和稳定性,还能影响金属原子的电子结构,从而调控其催化活性和选择性.理论上,MSI影响对SACs和pseudo-SACs尤为关键。这是因为在NPCs中,活性位点大多为远离金属-载体界面的配位不饱和原子(如金属表面、台阶和扭结处),而MSI则主要作用于界面处的金属原子,并且颗粒中大量的体相原子进一步削弱了MSI中电子转移对表面原子的影响,因而MSI有时对NPCs的催化性能的影响并不显著.相反,在SACs和pseudo-SACs中,所有金属原子都直接分散于载体表面并与其相互作用,导致MSI对其影响更为直接和关键.这意味着,SACs和pseudo-SACs中金属对MSI的变化应该更加敏感;相应地,MSI的调变对SACs和pseudo-SACs的影响应该要比对NPCs更为显著然而,必须指出的是,尽管这种推论在理论上具有合理性,但据我们所知,迄今为止尚未有系统的实验研究对此进行验证.在本文的研究中,我们设计合成了Pt/CoFe_(2)O_(4)ps

关 键 词：Strongmetal-support interaction Single-atom catalyst Pseudo-single-atom catalyst Size dependence Pt/CoFe_(2)O_(4)catalyst 

分 类 号：O643.36[理学—物理化学]