Spherical-structured　nano-/micromaterials　with　tunable　shell　architectures　and　compositions　are　becoming　increasingly　important　and　attractive　for　electrochemical　energy　conversion　and　storage.　Herein,　we　report　the　synthesis　of　novel　Ni–Co　alloy@carbon　microspheres　by　calcining　Co/Ni　bimetallic　metal-organic　frameworks　(MOFs)　prepared　by　a　facile　solvothermal　reaction.　Their　structures,　dimensions　and　electrochemical　performance　can　be　optimized　by　simply　tuning　the　Co/Ni　molar　ratio.　Benefiting　from　the　advantageous　structural　and　compositional　features,　the　obtained　Ni–Co　alloy@carbon　microspheres　display　exceptional　electrochemical　performance　when　used　as　counter　electrode　(CE)　catalysts　for　dye-sensitized　solar　cells　(DSSCs).　In　particular,　the　optimized　NiCo0.2@C　CE　delivers　an　impressive　power　conversion　efficiency　(PCE)　of　9.30%,　showing　a　∼15.7%　enhancement　compared　to　that　of　Pt　CE　(8.04%).　Additionally,　the　NiCo0.2@C　CE　also　demonstrates　a　good　long-term　electrochemical　stability　for　the　I3−/I−　electrolyte.　This　work　may　provide　new　options　for　the　design　and　preparation　of　efficient　electrocatalysts　with　novel　morphologies　and　desirable　compositions.　©　2017　Elsevier　B.V.