A nickel ion-incorporating zinc-mesoporous metal organic framework thin film nanocomposite modified glassy carbon electrode for electrocatalytic oxidation of methanol in alkaline media

In this work, we have successfully synthesized zinc-mesoporous metal-organic framework thin films (Zn-mMOFTFs) on the surface of a glassy carbon electrode (GCE) by self-assembly accumulation and electrochemical potentiostatic techniques. Then the electrodeposited Zn-MOFTFs were incorporated with Ni ions through the immersion of the obtained electrode in Ni(ii) solution to form the final modified electrode, Ni/Zn-mMOFTFs/GCE, which was characterized utilizing the various instrumental techniques. In electrochemical studies, the obtained modified electrode, Ni/Zn-mMOFTFs/GCE, showed enhanced electrocatalytic activity toward the oxidation of methanol (CH3OH) in alkaline media. The values of catalytic rate constant (k) and the electron transfer coefficient (alpha) for the electrooxidation of CH3OH on the Ni/Zn-mMOFTFs/GCE were obtained to be 1.43 x 10(4) cm(3) mol(-1) s(-1) and 0.56, respectively. The pseudo steady-state polarization method was employed for further investigation of the electrocatalytic oxidation of CH3OH on the Ni/Zn-mMOFTFs/GCE and the rate constant of the reaction k(2)Gamma = 2.866 x 10(-9) cm s(-1) and the ratio of k0-1/k01 = 2.08 x 10(8) were determined. These results showed that the incorporation of the Ni(ii) ions in the Zn-mMOFTFs produces a significant electrocatalytic activity toward the oxidation of CH3OH and consequently opens a new way to design a high-performance capable electrocatalyst for direct CH3OH fuel cell systems.

Automated summary

The study successfully synthesized Ni/Zn-mMOFTFs/GCE modified electrodes with enhanced electrocatalytic activity towards methanol oxidation. Further investigation revealed the potential application of these modified electrodes in direct methanol fuel cell systems.