Rational　design　and　controllable　synthesis　of　multiple　metal　components　according　to　chemical　composition　and　morphology　are　essential　for　obtaining　desirable　electrochemical　performance　for　efficient　hydrogen　production　because　of　the　morphology　and　synergistic　effects　of　different　components.　Herein,　we　report　an　approach　to　facilely　fabricate　bimetal　compounds　with　a　well-defined　hollow　nanoprism　structure　using　a　self-templated　strategy　to　synthesize　novel　hierarchical　NiCo-layered　double　hydroxide　(NiCo-LDH)　nanosheets　as　precursors　followed　by　in　situ　phosphorization.　Among　the　as-synthesized　products　of　different　mole　ratios　of　Ni/Co,　the　NiCo2-B-P　nanoprisms　that　integrate　the　advantages　of　a　hollow　structure,　an　optimal　Ni-Co　synergistic　effect,　and　a　unique　B-doped　CoP/Ni2P　bimetallic　phosphide　derived　from　NiCo-LDH　nanosheets　exhibit　excellent　hydrogen　evolution　reaction　(HER)　activity　in　an　alkaline　solution　at　10　mA　cm-2　with　the　lowest　overpotential　of　78　mV　and　long-term　stability.　This　study　may　offer　an　appropriate　structure　and　compositional　design　of　bimetallic　alkaline　HER　catalysts.　©