Synthesis and Treatment Parameters for Controlling Metal Particle Size and Composition in Cu/ZnO Materials鈥擣irst Evidence of Cu3Zn Alloy Formation

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• 作者：Salim Derrouiche ; H茅l猫ne Lauron-Pernot ; Catherine Louis
• 刊名：Chemistry of Materials
• 出版年：2012
• 出版时间：June 26, 2012
• 年：2012
• 卷：24
• 期：12
• 页码：2282-2291
• 全文大小：423K
• 年卷期：v.24,no.12(June 26, 2012)
• ISSN：1520-5002

文摘

This paper deals with the study of the conditions of obtention of small metal copper particles on ZnO using easy synthesis methods and activation treatments, which were found 鈥渆fficient鈥?for the preparation of copper particles on silica, that is, deposition鈥損recipitation with urea and incipient wetness impregnation. For the latter, four different copper precursors were used: copper(II) nitrate, acetylacetonate, bis-ethylenediamine, and tetraamine. Activation treatments were performed under different gas reducing conditions (H₂ or CO in N₂), temperatures between 280 and 350 掳C, and isotherm between 1 min and 2 h, with or without a precalcination step. Transmission electron microscopy (TEM), UV鈥搗isible spectroscopy, and X-ray diffraction (XRD) techniques were used to characterize the samples at the different stages of the synthesis route. The TEM results showed that it is not as easy as on silica to make small copper particles on ZnO. However, some experimental conditions were found to lead to particles around 4 nm: impregnation with copper acetylacetonate or copper bis-ethylenediamine, followed by calcination before reduction in H₂. The important result of this work is that depending on the final temperature of reduction under hydrogen, it was possible to form either metal Cu particles (280 掳C) or Cu₃Zn alloy particles (350 掳C); this was directly proved by XRD and indirectly by UV鈥搗isible spectroscopy. However, the formation of Cu₃Zn could be avoided if the reducing gas H₂ was replaced by CO in N₂. To our knowledge, this is the first time that the formation of Cu₃Zn alloy particles is evidenced in Cu/ZnO samples.
<h4>Keywords: h4> hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Cu%2FZnO&qsSearchArea=searchText">Cu/ZnO; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=nanoparticles&qsSearchArea=searchText">nanoparticles; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Cu&qsSearchArea=searchText">Cu; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Cu%E2%88%92Zn&qsSearchArea=searchText">Cu鈭抁n; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Cu1%E2%88%92xZnx&qsSearchArea=searchText">Cu_1鈭?i>xZn_x; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=Cu3Zn&qsSearchArea=searchText">Cu₃Zn; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=alloy&qsSearchArea=searchText">alloy; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=reduction+conditions&qsSearchArea=searchText">reduction conditions; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=impregnation&qsSearchArea=searchText">impregnation; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=deposition%E2%80%93precipitation&qsSearchArea=searchText">deposition鈥損recipitation; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=copper+nitrate&qsSearchArea=searchText">copper nitrate; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=copper+acetylacetonate&qsSearchArea=searchText">copper acetylacetonate; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=copper+tetraamine&qsSearchArea=searchText">copper tetraamine; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=copper+bis%5C-ethylenediamine&qsSearchArea=searchText">copper bis-ethylenediamine; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=catalyst&qsSearchArea=searchText">catalyst; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=TEM&qsSearchArea=searchText">TEM; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=UV%E2%88%92visible&qsSearchArea=searchText">UV鈭抳isible; hors" href="http://pubs.acs.org/action/doSearch?action=search&searchText=XRD&qsSearchArea=searchText">XRD