Synthesis of one-dimensional β-Ni(OH)2 nanostructure and their application as nonenzymatic glucose sensors

One-dimensional (1D) β-Ni(OH)2 nanostructure with high surface area have been successfully synthesized via the crystallization–dissolution–recrystallization growth mechanism. The reason why the 1D beta-Ni(OH)2 nanowires can be obtained is that the intermediates α-Ni(OH)2 crystals is internal unstable state and the reaction system switched from alkalescence to acidity with increasing of reaction time. The switch from alkalescence to acidity of reaction system attribute to the hydrolysis of CF3COONa which is the strong base–weak acid salt. In the initial stage, the hydrolysis of CF3COONa provides controlled quantities of OH− ions for the formation of α-Ni(OH)2 crystals. While the OH− supplies to the precipitation of Ni(OH)2, the CF3COOH of the system increases continually. Following the incessant increase of the concentration of CF3COOH, the reaction system switched from alkalescence to acidity. The unstable state of α-Ni(OH)2 crystals derived from that CF3COO−, H2O, and NO3− were intercalated into the interlayer space of α-Ni(OH)2 crystals. The unstable state of α-Ni(OH)2 crystals make these crystals easy to redissolute into the solution and recrystallizate. The unique morphology and large BET surface areas give β-Ni(OH)2 nanowires an advantage over the β-Ni(OH)2 nanosheets in the application for nonenzymatic glucose sensor. The nonenzymatic glucose sensor based on one-dimensional β-Ni(OH)2 nanostructure exhibits an enhanced electrocatalytic property, high sensitivity, and fast amperometric sensing toward oxidation of glucose.