Developing　efficient　catalysts　toward　both　oxygen　reduction　reaction(ORR)　and　oxygen　evolution　reaction(OER)　is　the　core　task　for　rechargeable　metal-air　batteries.　Although　integration　of　two　active　components　should　be　an　effective　method　to　produce　the　bifunctional　catalysts　in　principle,　traditional　techniques　still　can　not　attain　fine　tunable　surface　structure　during　material-hybridization　process.　Herein,　we　present　a　facile　short-time　in-situ　argon(Ar)　plasma　strategy　to　fabricate　a　high-performance　bifunctional　hybrid　catalyst　of　vacancy-rich　CoFe2O4　synergized　with　defective　graphene(r-CoFe2O4@DG).　Reflected　by　the　low　voltage　gap　of　0.79　V　in　two　half-reaction　measurements,　the　striking　capability　to　catalyze　ORR/OER　endows　it　excellent　and　durable　performance　in　rechargeable　Zn-air　batteries,　with　a　maximum　power　density　of　155.2　mW/cm(2)　and　robust　stability(up　to　60　h).　Further　experimental　and　theoretical　studies　validate　its　remarkable　bifunctional　energetics　root　from　plasma-induced　surface　vacancy　defects　and　interfacial　charge　polarization　between　DG　and　CoFe2O4.　This　work　offers　more　opportunities　for　reliable　clean　energy　systems　by　rational　interfacial　and　defect　engineering　on　catalyst　design.