{"title":"Site requirements for inhibition-free CO oxidation over silica-supported bimetallic PdCu alloys†","authors":"","doi":"10.1039/d4cy00255e","DOIUrl":null,"url":null,"abstract":"<div><p>Pd catalysts are highly active for CO oxidation but suffer from inhibition by NO at low temperatures (<150 °C). We posit that incorporation of Cu into the Pd catalyst will improve low-temperature CO oxidation activity and reduce inhibition from competitive adsorbers. To probe this hypothesis, a series of PdCu alloys with different Pd : Cu ratios were synthesized and tested in the temperature-programmed oxidation of CO in the presence and absence of NO. Incorporation of small amounts of Cu into Pd improves the reactivity, as well as the resistance to NO inhibition. Beyond this, Cu incorporation into the Pd has a detrimental effect on the activity for CO oxidation. Based on combined infrared and X-ray absorption spectroscopy studies, we show that high activity and resistance to inhibition requires alloying of Pd and Cu and the formation of a diverse surface, while surface segregation of Cu results in poor activity and inhibition.</p></div>","PeriodicalId":66,"journal":{"name":"Catalysis Science & Technology","volume":null,"pages":null},"PeriodicalIF":4.4000,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Catalysis Science & Technology","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/org/science/article/pii/S2044475324003423","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Pd catalysts are highly active for CO oxidation but suffer from inhibition by NO at low temperatures (<150 °C). We posit that incorporation of Cu into the Pd catalyst will improve low-temperature CO oxidation activity and reduce inhibition from competitive adsorbers. To probe this hypothesis, a series of PdCu alloys with different Pd : Cu ratios were synthesized and tested in the temperature-programmed oxidation of CO in the presence and absence of NO. Incorporation of small amounts of Cu into Pd improves the reactivity, as well as the resistance to NO inhibition. Beyond this, Cu incorporation into the Pd has a detrimental effect on the activity for CO oxidation. Based on combined infrared and X-ray absorption spectroscopy studies, we show that high activity and resistance to inhibition requires alloying of Pd and Cu and the formation of a diverse surface, while surface segregation of Cu results in poor activity and inhibition.
钯催化剂具有很高的一氧化碳氧化活性,但在低温(150 °C)下会受到氮氧化物的抑制。我们认为,在钯催化剂中加入铜可提高低温 CO 氧化活性,减少竞争吸附剂的抑制作用。为了探究这一假设,我们合成了一系列具有不同钯 :合成了一系列具有不同钯:铜比率的钯铜合金,并在有氮氧化物存在和无氮氧化物存在的情况下对一氧化碳的温度编程氧化进行了测试。在钯中掺入少量的铜可提高反应活性以及对氮氧化物抑制作用的抵抗力。除此之外,在钯中掺入铜会对 CO 氧化活性产生不利影响。根据红外线和 X 射线吸收光谱的综合研究,我们发现要想获得高活性和抗抑制性,需要将钯和铜进行合金化并形成多样化的表面,而铜的表面偏析则会导致低活性和抑制性。
期刊介绍:
A multidisciplinary journal focusing on cutting edge research across all fundamental science and technological aspects of catalysis.
Editor-in-chief: Bert Weckhuysen
Impact factor: 5.0
Time to first decision (peer reviewed only): 31 days