Efficient Pt electrocatalysts supported onto flavin mononucleotide–exfoliated pristine graphene for the methanol oxidation reaction

Due to its large surface area, high electrical conductivity as well as mechanical and thermal stability, pristine graphene has the potential to be an excellent support for metal nanoparticles (NPs), but the scarce amount of intrinsic chemical groups/defects in its structure that could act as anchoring sites for the NPs hinders this type of use. Here, a simple strategy based on the stabilization of pristine graphene in aqueous dispersion with the assistance of a low amount of flavin mononucleotide (FMN) is shown to yield a material that combines high electrical conductivity and abundance of extrinsic anchoring sites, so that pristine graphene–metal (Pd and Pt) NP hybrids with good dispersion and metal loading can be obtained from FMN–stabilized graphene. The activity of these hybrids towards the methanol oxidation reaction (MOR) both in acidic and alkaline media is studied by cyclic voltammetry (CV) and their stability investigated by chronoamperometry. The pristine graphene–Pt NP hybrid prepared by this simple, eco–friendly protocol is demonstrated to outperform most previously reported pristine graphene– and reduced graphene oxide–metal NP hybrids as electrocatalyst for the MOR, both in terms of catalytic activity and stability, avoiding at the same time the use of harsh chemicals or complex synthetic routes.Financial support from the Spanish Ministerio de Economía y Competitividad (MINECO) and the European Regional Development Fund (FEDER) through projects MAT2015-69844-R and MAT2016-76595-R is gratefully acknowledged. We also acknowledge partial funding by Plan de Ciencia, Tecnología e Innovación 2013-2017 del Principado de Asturias and FEDER through grant GRUPIN14-056. M.A-V. is thankful to MINECO and for his pre-doctoral contract. R.R.R acknowledges financial support from MINECO through “Juan de la Cierva” program (JCI-2012-12664)