A novel Pt@Te-reduced graphene oxide/polyimide composite catalyst for hydrogen evolution

A promising Pt@Te nanoparticles catalyst has been synthesized on the surface of the reduced graphene oxide/polyimide (rGO/PI) substrate. First of all, Te was deposited on the rGO/PI using electrochemical deposition method to obtain Te-rGO/PI that has various morphologies. Secondly, a monolayer Pb film was deposited on the Te-rGO/PI by the similar electrochemical method to get a transition state material of Pb@Te-rGO/PI. Finally, the target Pt@Te catalyst on the rGO/PI with large surface area was obtained by a chemical oxidation method, in which Pb was stripped off from the Pb@Te-rGO/PI by an oxygenation of H2PtCl6, while the oxygenation process, Pt replaced Pb to be deposited on the surface of Te-rGO/PI to form Pt@Te-rGO/PI. Then the prepared Pt@Te-rGO/PI was used as a working electrode to study the hydrogen evolution behavior in 0.5 mol/l H2SO4. By comparison the catalyst of sole Pt-rGO/PI nanoparticles, Pt@Te-rGO/PI catalyst considerably abated the demanding of Pt. And it shows excellent HER activities with a low overpotential of 0.1 V. The Tafel slope of 55 mV dec−1 reveals most likely the Volmer-Heyrovsky mechanism for hydrogen evolution reaction (HER). On the other hand, the catalyst displays satisfactory stability. This work may pave a potential pathway for synthesizing multi-morphology nano-Pt catalyst with high surface area for application in the study of HER.