Deep eutectic solvents as a versatile platform for wood modification: Lignocellulosic regulation and functional...

Deep eutectic solvents (DESs) have emerged as a highly versatile platform for wood modification and biomass processing due to their compositional tunability, mild reaction conditions and capacity for selective regulation of lignocellulosic components, thereby enabling the subsequent structural engineering and functionalization of wood. Compared to thermal treatment, chemical modification and impregnation techniques, DES modification can selectively remove lignin and hemicellulose, rearrange cellulose microstructures and reconstruct the cell-wall pore architecture while largely preserving the hierarchical structure of wood. This review systematically summarizes the major classes of DESs and their mechanisms of action in wood, establishing a treatment-structural regulation-performance modulation-application pathway and linking DES-induced lignocellulosic component regulation and cell-wall structural evolution to changes in wood properties and functional applications. It also evaluates key process parameters, including DES composition, water content, treatment temperature and duration, as well as synergistic intensification strategies such as thermal treatment, hot pressing and densification). Based on recent research progress, this review identifies the major challenges facing DES-modified wood, including environmental sustainability, solvent recovery, process stability and scale-up potential. Overall, DES-based modification has the potential to develop from a laboratory-scale approach into a platform for high-performance, low-carbon wood materials and sustainable bio-based engineering products.