The Research Of The Electrocatalytic Performance Of Nanostructured ZnO Towards Methanol

The growing global awareness of environment and sustainability triggered the research for future energy from clean power sources rather than pollutants. Direct methanol fuel cell (DMFC), which is a small, clean energy converter, is one of such promising candidates because of it’s less pollutant emission, low operating temperature, easy portability, and high energy conversion efficiency, and the high energy density and easy transportation of liquid methanol itself as fuel. However, DMFC is not yet commercially available, largely because of its low power density. With regard to the reasons for the low power density of DMFC, there are three strategies as following:(i) an enhancement of the activity of the anode catalyst for methanol oxidation, (ii) a low permeable electrolyte membrane to limit methanol crossover, and (iii) an improvement in the O2 reduction performance in the cathode, have been considered to decrease the over-potential. Among these considerations, the development of an efficient anode catalyst for methanol oxidation is the key issue for the enhancement of power density. As a result, not only Pt, Ru, Pd metalltic, but also Pt-based bimetallic catalysts (such as PtBi, PtNi, and PtRu) with various morphology have been used as an anode because of their outstanding performance in catalyzing the oxidation of methanol, and good results was achieved. However, the high cost and low utilization of these materials limit their commercial applications. Therefore, the development of an economic and efficient anode catalyst for methanol oxidation is still highly desired.Hence, in this paper, ZnO nanostructured arrays, nanorods and nanosheets, have been successfully grown on Ni foam by a simple hydrothermal growth method. Their electrocatalytic performance was investigated as oxidation catalysts of methanol in an alkaline media. The morphological characterization showed that the surface of Ni foams has been uniformly covered by nanostructured ZnO arrays. The ZnO nanorods were around 50 nm in diameter and lum in length. The thickness of the ZnO nanosheets was about 8 nm. The results showed that nanostructured ZnO nanorod has a good electrocatalytic activity for the methanol oxidation. Moreover, the electrocatalytic performance of ZnO nanorod and nanosheet were investigated in UV illumination and in dark. The results show that the catalytic performance of ZnO nanorod and ZnO nanosheet toward methanol can be enhanced by the UV illumination.