Oxygen　reduction　reaction　(ORR)　activity　and　durability　of　Pt　catalysts　should　be　both　valued　for　successful　commercialization　of　proton　exchange　membrane　fuel　cells　(PEMFCs).　We　offer　a　facile　one-pot　synthesis　method　to　prepare　Pt/CeO2/C　composite　catalysts.　CeO2　nanoparticles,　with　high　Ce(3+)concentration　ranging　from　30.9%　to　50.6%,　offers　the　very　defective　surface　where　Pt　nanoparticles　preferentially　nuclear　and　growth.　The　Pt　nanoparticles　are　observed　sitting　on　the　CeO2　surface,　increasing　the　PtCeO2　interface.　The　high　concentration　of　oxygen　vacancies　on　CeO2　surface　and　large　PtCeO2　interface　lead　to　the　strong　PtCeO2　interaction,　effectively　improving　the　ORR　activity　and　durability.　The　mass　activity　is　increased　by　up　to　50%,　from　36.44　mA　mg(-1)　of　Pt/C　to　52.09　mA　mg(-1)　of　Pt/CeO2/C　containing　20　wt.%　CeO2.　Pt/CeO2/C　composite　catalysts　containing　1030　wt.%　CeO2　loss　about　80%　electrochemical　surface　area　after　10,000　cycles,　which　is　a　fivefold　enhancement　in　durability,　compared　to　Pt/C　losing　79%　electrochemical　surface　area　after　2000　cycles.　(C)　2017　Hydrogen　Energy　Publications　LLC.　Published　by　Elsevier　Ltd.　All　rights　reserved.