Biochar decorated with gold nanoparticles for electrochemical sensing application

To distribute gold nanoparticles uniformly into porous biochar, a facile pyrolysis approach was developed. Dracaena sanderiana was first soaked in an aqueous solution of HAuCl4 as a precursor and then pyrolysed under a nitrogen atmosphere at high temperatures. The morphologies, structures, and properties of the gold nanoparticle-decorated biochar (Au-NPs/BC) nanocomposites were characterized by various electron microscopy, spectroscopic, and electrochemical methods. As-synthesized Au-NPs/BC nanocomposites possessed high porosities, large specific surface areas, and excellent electrical conductivities. Moreover, the preparative strategy was facile and cost-effective. Further, the potential applications of these Au-NPs/BC nanocomposites for electrochemical sensing of hydroquinone and catechol were explored. Sensitive and simultaneous determination of hydroquinone and catechol was realized with very low detection limits (in the nanomolar range) and high sensitivities.