Catalysis of oxygen reduction on electrochemically activated polycrystalline gold by Pd nanoislands in alkaline solution

Hydrogen Evolution on Reduced Graphene Oxide-Supported PdAu Nanoparticles

Hydrogen evolution reaction (HER) was investigated on reduced graphene oxide (rGO)-supported Au and PdAu nanoparticles in acid solution. The graphene spread over glassy carbon (rGO/GC) was used as a support for the spontaneous deposition of Au and Pd. The resulting Au/rGO and PdAu/rGO electrodes were characterized using atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) techniques. Phase AFM images have shown that the edges of the rGO sheets were active sites for the deposition of both Au and Pd. XPS analysis revealed that the atomic percentages of both Au and PdAu nanoparticles were slightly higher than 1%. The activity of the PdAu/rGO electrode for the HER was remarkably high, with the overpotential close to zero. HER activity was stable over a 3 h testing time, with a low Tafel slope of approx. −46 mV/dec achieved after prolonged hydrogen evolution at a constant potential.

Pd nanoparticles loaded onto a TiO2–C heterostructure via a photochemical strategy for efficient oxygen reduction reaction

In this paper, we successfully reduced Pd to TiO2–C heterostructure (Pd/TiO2–C catalyst) by photochemical reduction method. The directional transfer of electrons from TiO2–C to Pd catalyst strengthens MA and improves the durability of ORR.