Ruthenium Nanoparticles Confined in Covalent Organic Framework/Reduced Graphene Oxide As Electrocatalyst toward Hydrogen Evolution Reaction in Alkaline Media

Developing a highly efficient, nonprecious, and stable electrocatalyst toward hydrogen evolution reaction (HER) is important for the commercialization of water splitting technologies. The rational design of porous supports can effectively increase electric conductivity, active site exposure, and electrochemical active surface area of catalysts. Herein, we proposed a facile method for HER catalyst preparation, by which ruthenium nanoparticles can be incorporated into the hybrid of two-dimensional covalent organic framework/reduced graphene oxide (COF/rGO). The catalysts were synthesized through multirefluxing steps, the covalent organic framework was first supported on reduced graphene oxide, and ruthenium nanoparticles were then confined in the COF/rGO hybrid. The resulting catalyst exhibited a high HER performance with 42 mV of overpotential at 10 mA/cm2 and showed a low Tafel slope of 46 mV/dec in alkaline electrolyte. In addition, the catalyst exhibited good stability and durability during long-term discharging. These results indicated that the as-developing catalyst can be a viable alternative toward practical HER applications.