Plasma-Assisted Fabrication of Biomass-Derived Nanocomposite Catalysts for Tetrazole Production

A plasma-assisted strategy was developed for the synthesis of tetrazole derivatives using carbon-based nanocatalysts derived from biomass. Coconut coir was employed as a renewable carbon source to prepare a porous catalyst support, which was subsequently functionalized via N₂/H₂ nonthermal plasma treatment to introduce amino and carboxylic acid groups. The incorporation of TiO₂ and CuO nanoparticles further enhanced the catalytic performance by increasing surface acidity and electron density. The resulting catalysts efficiently promoted a multicomponent reaction between acetoacetanilide, aromatic aldehyde derivatives, and 5-aminotetrazole, affording tetrazole products in high yields (up to 96%) under mild conditions in an ethanol-water mixture. This approach provides a sustainable, recyclable, and efficient route for tetrazole synthesis, highlighting the synergistic effect of plasma activation and biomass-derived nanostructures.