Gold Nanoparticles Supported on Triazole-Functionalized Biochar as Nanocatalyst for Hydrogen Evolution from Aqueous Solution

Biochar is a material of great ecological interest obtained from the carbonization of biomass. Its structure is composed of graphene-like aggregates, and it contains useful functional groups such as carboxyl. Using these groups, biochar functionalization with triazole groups that improve support characteristics has been achieved to anchor and stabilize catalytically active gold nanoparticles (Au NPs). The Au NPs obtained were homogeneously distributed under biochar, with a size of 7.7 ± 3.5 nm. The efficiency of the nanomaterial was shown in nanogold-catalyzed hydrogen evolution from an aqueous solution containing B2(OH)4, with a maximum hydrogen generation of 715 mLH2 g-1 min-1 under optimized conditions (0.070 mmol of Au NPs and 0.300 mol L-1 of NaOH). This nanomaterial showed excellent efficiency in four successive catalytic cycles.