A facile route to a macroporous silver network for methanol oxidation

Abstract

A macroporous silver network was facilely synthesized using eggshell membrane as template and explored for methanol oxidation reaction, showing a significantly enhanced electrocatalytic ability compared with a traditional silver mirror electrode. The scanning electron microscopy observation showed a hierarchically ordered macroporous silver network because of the Ag⁺-protein binding. Energy dispersive X-ray spectrum, X-ray diffraction patterns and X-ray photoelectron spectra were used to characterize the resultant macroporous Ag network. The cyclic voltammetric studies at room temperature showed an excellent electrocatalytic activity for a methanol oxidation reaction in an acidic medium. The macroporous silver network was also checked in the electro-oxidation of methanol at high temperatures. A much higher electrocatalytic activity at 250 °C than that at 50 °C made them potential candidates for high-temperature proton exchange membrane fuel cells. The research opens a new insight to design low-cost, highly active and stable catalysts for methanol oxidation. The facile synthesis, excellent properties, alterable supports and low cost allow this material to be used in high-temperature direct methanol fuel cells.