Boosted electrochemistry properties of Cu4[(OH)0.29Cl0.71](OH)6 hexagonal prisms by 3D-cage atomic configuration of (100) facet

The Cu₄[(OH)_0.29Cl_0.71](OH)₆ hexagonal prisms, nanoplates and nanosheets are prepared by a simple hydrothermal method, and we have mainly investigated their electrochemistry properties. At 31.25, 62.5, 125, 250 and 500 mAg^-1, the discharge capacitances of hexagonal prisms (S0) electrode are 1186, 1023, 969, 934 and 918 mFg^-1, respectively; whereas 547, 508, 469, 438 and 375 mFg^-1 for hexagonal nanosheets (S10), respectively. The capacitance of 3-8 μm-long hexagonal prisms (0.25 m²g^-1) is 2 times higher than that of 50-100 nm-thick hexagonal nanosheets (3.54 m²g^-1), which is obviously beyond our imagination. The high capacitance of the former sample has been mainly attributed to the atom configuration of {100} facets and the high electrical conductivity. Compared with the hexagonal tunnel atom configuration of {001} facets, the three-dimensional (3D) cage atom configuration in {100} facets favors for the charge storage, thus leading to a higher capacitance of hexagonal prisms, which has rarely been reported yet. Further, the hexagonal prisms have a higher electrical conductivity than nanoplates and nanosheets, suggesting that the one-dimensional (1D) microstructure is beneficial to the electron transfer. This work enlightens us that the electrochemistry properties of materials can be improved by the exposed facets with unique atom configuration.