In　this　work,　a　series　of　the　Cu2O/CuO　hollow　sphere　heterojunction　catalysts　with　various　Cu+/Cu2+　ratios　were　designed　and　synthesized　to　improve　the　low-temperature　catalytic　activity　of　CO　oxidation.　The　physicochemical　properties　of　all　the　catalysts　were　charac-terized　by　the　SEM,　TGA,　N2-physisorption,　XRD,　FT-IR,　XPS,　and　H2-TPR.　The　results　revealed　that　the　Cu2O　hollow　sphere　catalyst　had　the　large　specific　surface　area　due　to　the　formation　of　the　hollow　structure,　which　could　provid　more　accessible　active　sites　for　the　gaseous　reactants.　Meanwhile,　the　Cu2O/CuO　hollow　sphere　heterojunction　catalysts　possessed　high　concentration　of　the　surface　oxygen　vacancies　and　further　promoted　the　adsorption　and　activation　of　O2.　As　a　result,　the　apparent　activation　energy　of　the　CO　oxidation　was　decreased　and　thus　low-temperature　activity　of　the　CO　oxidation　was　finally　promoted.　Therefore,　the　Cu2O/CuO　hollow　sphere　heterojunction　catalysts　were　considered　as　a　series　of　high-efficient　catalyst　candidates　for　CO　oxidation　with　promising　low　temperature　performance.　&　COPY;　2022　Hydrogen　Energy　Publications　LLC.　Published　by　Elsevier　Ltd.　All　rights　reserved.