Nickel Hydroxide Nanoflowers for a Nonenzymatic Electrochemical Glucose Sensor

Nickel hydroxide nanoflowers (f-Ni(OH)(2)) were synthesized in present work. The crystal structure of as-prepared sample is beta-Ni(OH)(2) phase (JCPDS # 14-0117). A nano composite film was fabricated by dispersing nano scale f-Ni(OH)(2) and carbon nanotubes (CNTs) into Nafion solution. The electrocatalytic oxidation of glucose in alkaline medium on the f-Ni(OH)(2)-CNT-Nafion composite (fNCN) modified glass carbon electrode (GCE) had been investigated. The prepared f-Ni(OH)(2)-CNT-Nafion / Glass Carbon electrode (fNCN/GCE) glucose sensor could produce large electrocatalytic oxidation current in glucose solution when the applied potential exceeds 0.32 V vs. SCE, which is much lower than the similar sensor based on Ni(OH)(2) nanosheets (s-Ni(OH)(2)) and is comparable to alpha-Ni(OH)(2) sensor. Amperometric measurements were done with different concentrations of glucose. The fNCN/GCE glucose sensor has high sensitivity and low detection limit at a potential of 0.45 V (vs. SCE). It showed a detection limit of 0.5 mu M (S/N = 3) and a sensitivity of 16.85 mu A mM(-1) (238.5 mu A mM(-1) cm(-2)) with a linear range from 0.1 to 1.1 mM. The K-m derived from Lineweaver-Burk equation is evaluated to be 4.25 mM, which is much lower than enzymatic glucose biosensor. (C) 2014 The Electrochemical Society. All rights reserved.