Polyol-mediated synthesis of mesoporous α-Ni(OH)2 with enhanced supercapacitance.

Flower-like α-Ni(OH)2 microspheres composed of nanowires are prepared by a solvothermal method using triethylene glycol and water as the mixed solvent. The formation of this unique structure is attributed to the synergetic effect of dissolution-recrystallization procedure, Ostwald ripening, and aggregative lateral attachment. Experimental results indicate that the dielectric constant, viscosity, and the chain lengths of the alcohols in the solvent may greatly affect the morphology and size of the as-obtained α-Ni(OH)2 samples. Because of the high Brunauer, Emmett, and Teller (BET) nitrogen sorption surface area of 318 m(2) g(-1) and large pore volume, this sample displays a maximum discharge specific capacity of 1788.9 F g(-1) at a discharge current density of 0.5 A g(-1). Besides, rate performance of this sample is also excellent, indicating that this sample is promising in electrochemical supercapacitors.