The　design　of　highly　stable　and　active　bifunctional　catalysts　for　electrolytic　water　remains　a　significant　challenge.　In　this　study,　self-supported　CoP/CNT/Ni2P　bifunctional　catalysts　with　three-phase　heterojunction　nano-　structures　were　constructed　by　a　multi-step　electrodeposition　and　phosphorylation　strategy.　X-ray　diffraction　analysis　and　transmission　electron　microscope　showed　that　CoP/CNT/Ni2P　was　a　three-phase　heterojunction　nanostructure,　and　scanning　electron　microscope　results　of　CoP/CNT/Ni2P　suggested　the　successful　introduction　of　carbon　nanotube　(CNT).　The　X-ray　photoelectron　spectroscopy　results　indicate　a　shift　in　the　elemental　binding　energy　in　CoP/CNT/Ni2P,　which　is　believed　to　contribute　to　the　electrocatalytic　reaction.　The　incorporation　of　CNT　enhances　charge　transfer　within　the　multiphase　catalyst　and　maximizes　the　exposure　of　catalytically　active　sites,　achieving　an　increase　in　catalyst　performance.　As　anticipated,　the　CoP/CNT/Ni2P　catalyst　displays　high　catalytic　activity　for　both　the　hydrogen　evolution　reaction　(61　mV　at　10　mA　cm_　2　)　and　the　oxygen　evolution　reaction　(342　mV　at　100　mA　cm_　2　),　in　addition　to　exhibiting　long-term　stability　at　a　current　density　of　10　mA　cm_　2　over　40　h.　The　electrolyzer　comprising　CoP/CNT/Ni2P(+,_)　necessitates　a　modest　operating　voltage　of　1.52　V　to　attain　10　mA　cm_　2　during　alkaline　water　splitting,　thereby　outperforming　the　commercial　catalyst　Pt/C||　IrO2　and　earlier　reports.　This　study　provides　guidance　for　the　development　of　ultra-high　activity　and　durability　catalysts　for　water　splitting.