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Density functional theory calculations are used to elucidate the interactions of small platinum clusters(Ptn,n=1~5)with the TiC(001)surface.The results are analyzed in terms of geometric,energetic and electronic properties.It is found that,a single Pt atom prefers to be adsorbed at the C-top site,while a Pt2 cluster prefers dimerization and a Pt3 cluster forms a linear structure on the TiC(001).As for the Pt4 cluster,the three-dimensional distorted tetrahedral structure and the two-dimensional square structure almost have equal stability.In contrast with the two-dimensional isolated Pt5 cluster,the adsorbed Pt5 cluster prefers a three-dimensional structure on TiC(001).From these results,we found that:with increasing the number of adatoms,the absorbed Pt atoms can form dimer(Pt2),linear(Pt3),square or distorted tetrahedral(Pt4)and three-dimensional (Pt5)structures,which can be attributed to the competition between the Pt-Pt interaction and the Pt-C interaction.Substantial charge transfer takes place from TiC(001)surface to the adsorbed Ptn clusters,resulting in the negatively charged Ptn clusters.Their magnetization is quenched after interacting with TiC(001)surface,as revealed by the intensities and positions of the spin up and down PDOS plots,which is attributed to the charge redistribution during the interaction with the substrate.At last,the d-band centers of the absorbed Pt atoms and their implications in the catalytic activity are discussed.This work highlights the potential of using TiC(001)as a potential replacement of the C support of the Pt catalyst,which is widely used in the traditional electrochemical device.