Wood-based composite for efficient cryogenic energy storage and thermoregulation in residential buildings in cold regions

Maintaining the temperature of residential buildings in cold areas is vital for saving energy and reducing CO2 emissions. To this end, a cryogenic energy-storage wood material (known as PPD) comprising polylactic acid (PLA), lauric acid (LA), capric acid (CA), polyethylene glycol (PEG), nanosized zinc oxide (nano-ZnO), and dehemicellulose Chinese fir (DCF) was synthesized herein. The polymer structure of PLA and porous architecture of wood considerably enhanced the encapsulation efficiency of the prepared energy-storage materials. PPD composites demonstrated an exceptionally high latent heat of 16.29-29.87 J & sdot;g- 1, which resulted in broad temperature regulation ability, ranging from-12.5 degrees C to 38.8 degrees C, and good recyclability for over 200 thermal cycles. Furthermore, PPD realized distinct solar-to-thermal energy conversion with a solar-absorption capacity of 18.5 %-40.8 % throughout the solar spectrum. In particular, the esterification reaction between the -COOH groups in the PLA molecular chain and -OH groups in the cellulose chains securely anchored PCMs within the lumens of the wood cells. This process enhanced the chemical stability of PPD. Life cycle assessment results indicated that the synthesis of PPD had a relatively minor overall environmental impact. Thus, this study introduces a pioneering method that employs wood-derived energy-storage materials as components suitable for portable energy-storage devices, passive cooling systems, and energy-storage devices in cold climates.