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Precious metal-support interaction plays an important role in thermal stability and catalytic performance of the automotive exhaust catalysts.The support is not only a carrier for active compounds in catalysts but also can improve the dispersion of precious metals and suppress the sintering of precious metals at high temperature;meanwhile,noble metals can also enhance the redox performance and oxygen storage capacity of support.The mechanism of metal-support interactions mainly includes electronic interaction,formation of alloy and inward diffusion of metal into the support or covered by support.The form and degree of precious metal-support interaction depend on many factors,including the content of precious metal,the species of support and metal,and preparation methods.The research results about strong metal-support interaction(SMSI) gave a theory support for developing a kind of new catalyst with excellent performance.This paper reviewed the interaction phenomenon and mechanism of precious metals(Pt,Pd,Rh) and support such as Al2O3,CeO2,and CeO2-based oxides in automotive exhaust catalysts.The factors that affect SMSI and the catalysts developed by SMSI were also discussed.
Precious metal-support interaction plays an important role in thermal stability and catalytic performance of the automotive exhaust catalysts. The support is not only a carrier for active compounds in catalysts but also can improve the dispersion of precious metals and suppress the sintering of precious metals at high temperature; meanwhile, noble metals can also enhance the redox performance and oxygen storage capacity of support. mechanism of metal-support interactions mainly includes electronic interaction, formation of alloy and inward diffusion of metal into the support or covered by support. form and degree of precious metal-support interaction depend on many factors, including the content of precious metal, the species of support and metal, and preparation methods. The research results about strong metal-support interaction (SMSI) gave a theory support for developing a kind of new catalyst with excellent performance.This paper reviewed the interaction phenomenon and mechanism of pr ecious metals (Pt, Pd, Rh) and support such as Al2O3, CeO2, and CeO2-based oxides in automotive exhaust catalysts. The factors that affect SMSI and the development of the catalysts by SMSI were also discussed.