From Co-MOF to CoNi-MOF to Ni-MOF: A Facile Synthesis of 1D Micro-/Nanomaterials.

Controlling the growth of metal-organic frameworks (MOFs) at the micro-/nanoscopic scale will result in new physical properties and novel functions into the materials without changing the chemical identities and the characteristic features of the MOFs themselves. Herein, we report a facile approach to synthesize a series of MOFs [Co-MOF, CoxNiy-MOFs (x and y represent the molar ratio of Co2+ and Ni2+ and x/y = 1:1, 1:5, 1:10, 1:15, and 1:20), and Ni-MOF] with a one-dimensional micro-/nanoscaled rod-like architecture. From Co-MOF to CoxNiy-MOFs to Ni-MOF, the diameters of the rods turn to be spindly with the increase of Ni2+ content which will facilitate the supercapacitor performances. Interestingly, Co1Ni20-MOF exhibits a highest specific capacity of 597 F g-1 at 0.5 A g-1 and excellent cycle performance (retained 93.59% after 4000 cycles) among these MOF materials owing to its micro-/nanorod structure with a smaller diameter and the synergy effect between the optimum molar ratio of Co2+ and Ni2+.