Muscle supercompensation inspired high-strength partially dissolved-regenerated cellulose biochar as the matrix of phase change materials for thermal storage

Balsa wood is widely planted as a light wood and easily available. However, the low strength of balsa wood limits its application scenarios. Based on the concept of muscle supercompensation, we reported cellulose partial dissolution and regeneration methods of wood to synthesize high strength matrix for preparation of efficient shape-stable phase change materials (ss-PCMs). Notably, part of the cellulose of the balsa wood was deconstructed, and a nano-scale entangled regenerated cellulose structure was formed in ethanol. The obtained carbonized cellulose regeneration wood (CRW) shows a hierarchically porous network with high mechanical strength and the specific surface area of CRW was around 17 times higher than that of natural balsa wood. The CRW exhibited high adsorption capacity for tetradecanoic acid (TA), and the maximum content of TA adsorbed in CRW was calculated to be 90.3%. Moreover, the CRW based ss-PCMs (CRPs), prepared by using CRW as carrier and TA as core material, can effectively improve the photo-thermal conversion efficiency of CRPs to 83.6%. This "wood supercompensation" strategy has the merits of simple and degradability, which provides a new approach for the recycle of lignocellulose and a promising way for the production of ss-PCM with high strength and excellent energy storage capacity.