Supramolecular Gelation of Hydrogen Peroxide: Reconciling Safety and Reactivity

Hydrogen peroxide (H₂O₂) is a versatile green oxidant, but its industrial application is plagued by safety risks due to impurity-induced exothermic decomposition and leakage. Conventional stabilizers compromise reactivity, creating a persistent safety-reactivity paradox. Herein, this challenge is resolved through a supramolecular gelation strategy using a glycyrrhizic acid (GA) and polyvinyl alcohol (PVA) binary system, transforming aqueous H₂O₂ into mechanically robust gels. The resulting gel exhibits exceptional mechanical strength (storage modulus >3600 Pa), thixotropy, and long-term stability (>6 months), effectively eliminating leakage. Crucially, the gel matrix suppresses H₂O₂ decomposition by up to 212-fold in the presence of metal contaminants (e.g., Fe³⁺, Cu²⁺, MnO₂) by slowing convective mixing and isolating impurities via a bubble barrier, thereby preventing thermal runaway. Remarkably, the shear-thinning properties of the gel enable the release of H₂O₂ with uncompromised reactivity, achieving efficient sulfoxidation and alcohol oxidation with yields comparable to those of liquid H₂O₂. This work establishes supramolecular gelation as a transformative platform for the safe utilization of H₂O₂ in industrial processes without sacrificing oxidative efficiency.