Effect of Sodium Terephthalate on the Electrocatalytic Performance of Active Self-Supporting Nanoporous PdAg Catalysts

Abstract

Direct-methanol fuel cells (DMFCs) have become a hot research topic in the energy field due to their excellent energy conversion efficiency and environmental sustainability. Optimization of catalyst preparation strategy is the key to enhance the performance of DMFC. In this study, melt quenching is employed to synthesize Al–Pd–Ag precursor alloy ribbons, and self-supported nanoporous Pd–Ag catalysts with high activity are successfully prepared by a precisely controlled dealloying process. The catalysts are characterized microstructurally and tested electrochemically, and their performance is compared with samples without sodium terephthalate addition and with commercial Pt/C and Pd/C catalysts. In the results, it is shown that the maximum peak current density of methanol electrocatalytic oxidation is significantly enhanced to 1451.16 mA mg⁻¹ with the addition of 15 mM sodium terephthalate, which is about 6.6 times higher than that of the unadded samples, and the catalytic performance is improved by a factor of 7.7 and 12.0, respectively, compared to those of commercial Pt/C and Pd/C. This remarkable performance enhancement is attributed to the innovative dealloying method, which not only refines the catalyst structure but also achieves a significant increase in catalytic performance through the assistance of active self-supporting nanoporous structures and interfacial synergistic effects between palladium and silver.