“…The layered TMSe has three types of atomic configurations: octahedral coordinated 1T, triangular prism coordinated 2H (hexagonal symmetry), and 3R (rhombic symmetry) . On the other hand, the nonlayered selenides are composed of FeSe 2 , ZnSe, Cu 2 Se, CuSe, Ni 3 Se 4 , Ni 0.85 Se, Cu 3 Se 2 , Mo 6 Se 8 , CoSe 2 , Cu 2– x Se, Co 0.85 Se, Ag 2 Se, NiCo 2 Se 4 , and Ni 0.75 Fe 0.25 Se 2 . ,− In comparison, these nonlayered selenides have relatively high electrical conductivity, metallic properties, and unique electronic structure. The electronic properties of TMSes strongly determine their electrochemical performances.…”