Carbon black-heteroatom-doped graphene aerogel hybrid supported platinum nanoparticles as electrocatalysts for oxidation of methanol and formic acid

Supported catalysts are generally used for electrochemical reactions in fuel cells. Due to their superior properties in these reactions, platinum nanoparticles are preferred over carbon-structured support materials. Commercial carbon support material such as carbon black (Vulcan XC-72) is widely used alone for the deposition of platinum particles on the surface. But this support material when used alone is easily affected from the operating conditions of methanol and formic acid oxidation resulting from chemical reaction. Graphene aerogels (GA) are the graphene-based materials that are important discoveries in nanotechnology, recently. These materials are being investigated as support materials in fuel cell catalysts. In this study, carbon black was used together with GA and heteroatom-doped GA, as support materials. Three different hybrid carbon (50:50) supported Pt nanoparticles, namely, Pt/GA-C (carbon black and GA), Pt/NGA-C (carbon black- and nitrogen-doped GA), and Pt/BGA-C (carbon black- and boron-doped GA) were synthesized by using, first, the modified Hummers method, second, hydrothermal treatment for support materials, and microwave irradiation method for Pt nanoparticles formation on support materials. The hybrid supported catalysts were characterized using scanning electron microscope, energy dispersion spectroscopy, BET, X-ray diffractometer, transmission electron microscope, Raman, X-ray photoelectron spectroscopy, inductively coupled plasma mass spectrometry. The catalysts analysis was studied using cyclic voltammetry, impedance, and short-term durability. The Pt/BGA-C catalyst showed the highest catalytic activity for both formic acid and methanol oxidation.

Automated summary

Supported catalysts are widely used in fuel cells, and platinum nanoparticles are preferred as they have superior properties. Carbon black has commonly been used as a support material, but it is easily affected by the operating conditions. Graphene aerogels (GA) have recently been discovered to be important graphene-based materials in nanotechnology and are being investigated as support materials. In this study, carbon black was used together with GA and heteroatom-doped GA to synthesize three different hybrid carbon-supported Pt nanoparticles. The Pt/BGA-C catalyst showed the highest catalytic activity for both formic acid and methanol oxidation.