Highly durable Pt nanoparticle-supported carbon catalysts for the oxygen reduction reaction tailored by using an ionic liquid thin layer

Pt nanoparticles monodispersed in an ionic liquid (IL), which can be readily prepared by magnetron sputtering onto an IL, are a key material for tailoring highly durable Pt nanoparticle-supported carbon electrocatalysts, e.g., Pt nanoparticle-supported single-walled carbon nanotubes (Pt-SWCNTs) and Vulcan (R) XC-72 (Pt-Vulcan (R)), for the electrochemical oxygen reduction reaction. The durability largely surpasses that of one of the commercially available Vulcan (R) XC-72-based catalysts, TEC10V30E. The differences were very obvious from the results of electrochemical measurements, ex situ TEM observation, and in situ SEM/STEM observation; that is, considerable damage by carbon corrosion was recognized for the TEC10V30E, but it was not the case for the Pt-SWCNT and Pt-Vulcan (R). The unexpected high durability should be due to the suppression of carbon corrosion by the ionic liquid thin layer that exists between the Pt nanoparticles and carbon support.