An Abiotic Cu/COOH Nanozyme for Cellulose Depolymerization and One-Pot Conversion into a Triazole Surfactant in...

Cellulases employ a conserved pair of carboxylic acids to cleave the β-1,4-glycosidic bonds in cellulose with high selectivity under mild conditions, but enzyme cost, stability, and recyclability remain bottlenecks in biomass conversion. We report a molecularly imprinted nanozyme that cleaves cellulose in water through the cooperative action of a Cu(II) Lewis acid and a Brønsted acid (COOH). The abiotic catalytic dyad promotes efficient hydrolysis of cellulose over pH 4-7.5 and also in unbuffered water, following a mechanism similar to that in retaining glycosidases. A rate acceleration of 2.4 × 10⁷ relative to the uncatalyzed background is observed in 90 °C water, translating to a catalytic proficiency of 10¹¹ M^-1. The hydrolytic intermediate may be intercepted and funneled into CuAAC to furnish a nonionic triazole-linked surfactant directly from cellulose, i.e., 4-butyl-1-(β-d-glucopyranosyl)-1H-1,2,3-triazole. As a cross-linked polymeric nanoparticle, the nanozyme is thermally robust (no detectable loss of activity after 3 days in boiling water), tolerates 130 °C water, and is reusable (≈80% activity retained after 10 cycles). These results demonstrate a recyclable route to depolymerize and derivatize cellulose with enzyme-like acceleration and chemical-catalyst robustness.