Biomolecule-Driven Supramolecular Gelation of Graphene Oxide: A Sustainable Route to Graphene–Metal Nanohybrid Gels with Catalytic Efficiency

A sustainable and efficient approach has been developed for the fabrication of graphene-based nanohybrid gels via supramolecular gelation of graphene oxide (GO) using uric acid as a biologically relevant cross-linker. Gelation occurred under mild aqueous conditions through non-covalent interactions between uric acid and oxygenated functional groups on GO. The resulting GO-based gel was subsequently transformed into a graphene-based nanohybrid gel embedded with noble metal nanoparticles (Au, Ag) through in situ co-reduction using ascorbic acid as an environmentally benign reducing agent. Comprehensive structural and morphological analyses confirmed the retention of the gel network post-reduction and the uniform distribution of metal nanoparticles. Among the synthesized materials, the Au nanoparticle containing graphene-based gel exhibited excellent catalytic activity in the reduction of 4-nitrophenol, demonstrating high efficiency, structural stability and recyclability. This work presents a green and scalable strategy for developing functional soft materials, offering significant potential for applications in catalysis and nanomaterial-based technologies.