Solvent-directed regeneration of nanocellulose with tunable morphology and interfacial properties

Dissolution-regeneration nanocellulose (DNCs) offer a sustainable alternative to conventional nanocellulose, yet precise control over morphology and interfacial properties remains a key challenge to its broader technological use. Here, we present a solvent-directed strategy that programs the structure of DNCs directly from a single biomass source. By varying the alkyl chain length in superbase-based ionic liquids (SILs), we modulated cellulose-solvent interaction, thereby controlling cellulose chain scissoring and reassembly. This yields tunable DNCs with prescribed degree of polymerization (DP), crystallinity (CrI), aspect ratio, and surface wettability. Longer-chain solvents exhibit lower mass transfer capacity and weaker hydrogen bonding with cellulose, which collectively suppress cellulose degradation and yield DNCs with higher aspect ratios and stronger interfacial affinity. As a compact validation, we use Pickering emulsions (PE) to quantify interfacial anchoring and network formation, observing reduced droplet sizes and enhanced stability with higher-aspect-ratio and more hydrophobic DNCs; we further illustrate utility by encapsulating phase-change materials with high enthalpy storage and minimal leakage. Together, by decoupling DNC property control from feedstock, this work delivers a general and solvent-programmable platform for tailored nanocellulose and bio-based interfacial systems.