RuTe2 Decorated Carbon Nanofiber Electrocatalyst Synthesized via a Sustainable Method for Electrochemical Hydrogen Evolution in Acidic and Alkaline Electrolytes

A novel ruthenium ditelluride (RuTe2) catalyst supported by graphitized carbon nanofibers (GNF) has been synthesized developing a straightforward, environmentally friendly, and cost-effective method. Characterization studies indicated that the formation of crystalline RuTe2 nanoparticles uniformly immobilized at the step edges within the internal cavity of GNF support, with an average nanoparticle size of ~4 nm, as well as the external surface of GNF. The electrocatalytic performance of RuTe2/@GNF in the hydrogen evolution reaction was investigated in both acidic and alkaline mediums. The results were compared with those of commercial platinum nanoparticles on activated carbon (Pt/C), as well as with hollow GNF and GNF-supported metallic ruthenium nanoparticles. The results indicated that GNF-supported RuTe2 exhibited a comparable HER performance to state-of-the-art Pt/C catalyst and suppressed the HER activity of other control materials. Increased HER activity was attributed to the confined space of step edges enabled the robust and active catalytic sites and facilitated the HER in a nanoscale environment. Additionally, the highly conductive GNF support functioned as an effective electrical bridge between the nanoparticles and the macroscopic electrode. This configuration not only facilitated efficient charge transfer between the electrolyte and the catalyst but also enhanced overall performance. As a result, RuTe2/@GNF served as a bifunctional catalyst in both mediums, facilitating enhanced proton adsorption/desorption process and effectively overcoming water dissociation barriers. This study paves the way for developing novel sustainable ruthenium chalcogenide-based catalysts that are alternatives to traditional platinum catalysts, highlighting their potential use for efficient hydrogen generation.