Yolk-shell　structures　based　on　transition　metal　chalcogenides　(TMCs)　have　broad　application　prospects　in　energy　conversion/storage　fields.　In　this　work,　a　facile　step-wise　synthetic　strategy　was　used　to　synthesize　the　yolk-shell　structured　polyhedrons.　The　intermediate　named　as　ZIF-67@Co-Fe　PBA　nanocrystal　was　formed　by　the　reaction　between　Co2+　released　from　ZIF-67　polyhedrons　and　[Fe(CN)(6)](3)-hydrolyzed　from　K-3　[Fe(CN)(6)].　N-doped　carbon/CoSe2@Co-FeSe2(CoSe2-NC@CoFeSe2)　and　N-doped　carbon/CoS2@Co-FeS2(CoS2-NC@Co-FeS2)　polyhedrons　with　yolk-shell　structures　were　prepared　by　modifying　the　ZIF-67@　Co-Fe　PBA　nanocrystals　in　the　annealing　process　and　they　have　been　applied　in　dye-sensitized　solar　cells　(DSSCs).　Noteworthily,　CoSe2-NC@Co-FeSe2　and　CoS2-NC@Co-FeS2　yolk-shell　polyhedrons　showed　high　catalytic　activity　in　accelerating　the　reduction　of　triiodide　in　DSSCs　because　of　the　distinctive　structural　characteristics　and　favorable　chemical　compositions.　The　power　conversion　efficiency　(PCE)　of　9.61%　and　9.18%　were　obtained　by　CoSe2-NC@Co-FeSe2　and　CoS2-NC@Co-FeS2　based　DSSCs,　respectively,　which　were　both　superior　to　that　of　Pt　(8.15%).　This　as-designed　approach　implies　the　new　perspective　to　prepare　more　types　of　TMCs　with　yolk-shell　structures　in　multitudinous　areas　of　energy　conversion.　(C)　2019　Elsevier　Ltd.　All　rights　reserved.