One-step stabilizer-free synthesis of porous bimetallic PdCu nanofinger supported on graphene for highly efficient methanol electro-oxidation

Abstract

Labor-saving preparation of highly active electrocatalysts for electrochemical energy conversion is extremely critical to the development of portable electronic devices. In this work, a hybrid catalyst of porous bimetallic PdCu nanofinger supported on graphene was simply synthesized by a one-step stabilizer-free method. The described method, carried out under room temperature without complicated procedures, not only abandoned the electrochemically hindered organic stabilizers during the synthesis, but also made the as-prepared catalyst with bimetallic composition strongly couple to graphene nanosheets. Meanwhile, it also provided the catalyst with large surface area and hierarchical pore structures via the spatially interconnected finger-like nanoparticles. As a result, the catalyst exhibited a synergistically enhanced electrocatalytic activity (2025.6 mA/mgPd) and stability for methanol electro-oxidation reaction, which was superior to the commercial Pd/C catalyst and the other reported Pd-based catalysts. In addition, the electrocatalytic performances could be easily adjusted by regulating the catalyst composition via this facile synthesis. These findings suggested a straightforward method to prepare the practical electrocatalysts with low cost and high activity for the fuel cell technologies.