Optimizing　the　interaction　between　metal　active　centers　and　supports　by　tuning　crystal　facets　is　an　effective　strategy　to　improve　the　activity　and　stability　of　catalysts.　Herein,　α-MnO2nanowires　with　different　exposed　crystal　facets　(respectively　(310),　(110)　and　(100))　were　synthesizedviaa　facile　hydrothermal　method　to　promote　the　activity　of　an　Au/α-MnO2catalyst　for　propane　combustion.　Results　reveal　that　Au/α-MnO2-110　exhibits　the　highest　catalytic　activity,　achieving　90%　propane　(2500　ppm)　conversion　at　just　216　°C　(apparent　activation　energy　as　low　as　50.2　kJ　mol−1).　Compared　with　Au/α-MnO2-310　and　Au/α-MnO2-100,　Au/α-MnO2-110　with　the　largest　quantity　of　oxygen　vacancies,　strong　reducibility,　and　high　surface　oxygen　mobility　possesses　the　best　capability　for　adsorbing　and　activating　oxygen　molecules.　DFT　results　reveal　that　the　(110)　facet　of　α-MnO2has　the　lowest　formation　energy　of　oxygen　vacancies　(Evo(110)　=　0.6　eV),　suggesting　the　presence　of　weak　surface　Mn-O　bonds,　facilitating　the　formation　of　Auδ+species　and　therefore　promoting　C-H　bond　breaking　in　propane.　This　work　highlights　a　new　strategy　for　the　design　of　efficient　catalysts　for　stable　light　alkane　low-temperature　decomposition　by　surface　exposed　facet　engineering.　©　The　Royal　Society　of　Chemistry　2020.