The　pseudocapacitive　materials,　like　spinel　NiCo2O4　(NCO),　that　use　Faradaic　reactions　to　store　charge　have　been　widespread　paid　attention　for　supercapacitors　application.　So,　it　is　a　basic　fundamental　guideline　that　the　preparation　of　higher-performance　pseudocapacitive　materials　depends　on　achieving　and　accelerating　more　Faradaic　reactions　in　the　aspect　of　electrodes.　In　this　work,　based　on　the　mentioned　principle,　we　report　a　facile　method　that　could　significantly　promote　the　capacity　of　NiCo2O4　nanoelectrode　through　annealing　precursor　nanowires　(NWs)　in　different　volume　ratios　of　N-2　and　O-2　condition.　The　pristine　NCO　(V-N2:　V-O2　=　0:　1)　only　exhibited　inferior　performance　with　a　specific　capacitance　of　0.88　F　cm(-2)　(338.5　F　g(-1)　at　2mA　cm(-2))　and　capacitive　retention　of　54%　from　2　to　30mA　cm(-2).　While,　for　a　comparison,　the　highest　comprehensive　performance　of　NCO-9　(V-N2:　V-O2　=　9:　1)　electrodes　delivered　superior　specific　capacitance　of　3.8　F　cm(-2)　(1461　F　g(-1)　at　2mA　cm(-2)),　excellent　rate　retention　of　77%　and　good　cycling　stability.　These　boosted　pseudocapacitive　properties　both　in　capacity　and　rate　capability　are　attributed　to　the　severe　oxygen　vacancy　defects　introduced　in　nitrided　NCO　NWs.　The　involving　richness-enabled　oxygen　defects　significantly　enhance　the　electron/ions　transportation,　and　then　efficiently　alter　the　well-known　capacitive　surfacial　reaction　into　bulk　pattern　in　the　charge-discharge　cycles.　This　dramatically　increased　electron/ions　kinetics　and　electrochemical　cites　for　Faradaic　reactions.　These　results　provide　a　deep　insight　into　correlating　oxygen　vacancies　induced　structural　and　chemical　evolution　on　enhanced　capacitive　performances　of　redox-active-NiCo2O4　materials.　(C)　2018　Elsevier　Ltd.　All　rights　reserved.