Because　of　the　strong　electromagnetic　field　at　the　corners　and　more　tunable　surface　plasmon　resonance　(SPR)　bands　in　the　visible　and　infrared　regions,　gold　triangular　nanoprisms　can　be　applied　to　more　fields.　Compared　with　monometallic　nanomaterials,　polymetallic　nanomaterials　are　composed　of　multiple　metals　and　possess　many　special　optical　properties.　Recently,　structurally　novel　Pt-based　polymetallic　nanostructures　have　attracted　much　attention　due　to　their　superior　catalytic　performance.　In　this　study,　gold　triangular　nanoprisms　were　prepared　by　the　seed　growth　method.　By　adjusting　the　amount　of　seeds,　gold　triangular　nanoprisms　of　different　sizes　were　formed.　By　changing　the　concentration　of　Cetyltrimethylammonium　Bromide　(CTAB)　and　Cetyltrimethylammonium　chloride　(CTAC),　the　purification　process　of　gold　triangular　nanoprisms　was　adjusted　to　make　gold　triangular　nanoprisms　more　uniform.　The　synthesis　of　Pt-Au　triangular　nanoprisms　and　the　switching　between　etching　and　deposition　dominated　in　the　reaction　is　controlled　by　adjusting　the　volume　of　AgNO3,　H2PtCl6,　and　the　size　of　gold　triangular　nanoprisms.　At　relatively　high　H2PtCl6　concentrations,　the　etching　process　dominates;　at　lower　H2PtCl6　concentrations,　the　etching　process　is　restrained.　Due　to　the　good　catalytic　performance　of　Pt　itself　and　the　rough　surface-induced　Surface-Enhanced　Raman　Scattering　(SERS)　improvement　of　the　nanoparticles,　the　application　of　Pt-Au　triangular　nanoprisms　in　the　fields　of　catalysis　and　SERS　is　proposed.　©　2022　Elsevier　B.V.