Organic ligand-free PtIr alloy nanostructures for superior oxygen reduction and evolution reactions

In the thermal decomposition method, organic solvents, ligands, and compounds are usually used under an N 2 atmosphere to synthesize pure metal and alloy nanostructures with high specific surface areas. However, the organic materials, which are used during the synthesis of metallic nanostructures, need to be completely eliminated to obtain cleaned surface states for effective catalytic reactions in aqueous atmospheres. Herein, we synthesize PtIr nanostructures using a thermal decomposition method, followed by a heating process of the nanostructures under an air atmosphere to eliminate the organic materials covering the surface of PtIr catalysts. The heated PtIr alloy nanostructure catalysts represent the superior oxygen reduction and evolution performance due to an increased electrochemical active surface area caused by the complete removal of organic materials.