Study on Electrochemical Behavior of Methane at Nickel Electrode Modified with Nickel Hydroxide in Alkaline Solution

The nickel hydroxide modified nickel (NMN) electrode was prepared by cycling the potential of a nickel electrode in 1.0 molldrL^-1NaOH solution that exhibited better electro-activity for the oxidation of methane. The NMN electrode was investigated in varies alkaline conditions by cyclic voltammetry (CV) in detail. The related electrochemical oxidation reaction of methane at the NMN modified electrode was first proposed by normal pulse voltammetry (NPV) under the experiment condition. The results indicated that, in 1.0 molldrL^-1NaOH solution, scan rate 20 mVs^-1, the potential window 0.0~0.6 V, the gas flow rate 200 mLmin^-1, the oxidation peak current of the NMN electrode was increased by methane concentration. The anodic peak current increased linearly with the increase volume concentration of methane. A linear equation y=0.01059+0.0478x with a correlation coefficient of 0.990 is obtained in methane concentration range of 1.50 to 16.0% relative to Ag/AgCl reference electrode. The relative standard deviation is 1.80% (n=5) at room temperature.