Hydrophilic cellulose nanocrystals (CNC) are typically poorly dispersed in non-polar polymer matrices and, hence, a method for the surface modification of CNC is developed for improving this dispersion. This method included an esterification reaction with acetic anhydride, butyric anhydride, and caproic anhydride. The particle size distribution (range of sizes: 80–310 nm) of CNC was determined. The SEM-EDAX indicated that (i) the structure of CNC was maintained even after incorporation of the acid anhydride and (ii) the carbon C content of modified-CNC was higher than that of pure CNC. The chemical structure of modified-CNC was identified via FT-IR and ¹³C NMR spectroscopy. The contact angle of CNC and modified-CNC with water and methylene iodide was measured. The surface energy of modified-CNC was lower than that of pure CNC. Thermal-property measurements indicated that the initial decomposition temperature (based on 5 wt%) of the modified-CNC was slightly higher than that of CNC. Poly(butylene succinate) (PBS) composites were obtained by mixing modified-CNC into a PBS matrix via simple melt blending of a double screw. The PBS/modified-CNC composites were investigated via DSC and XRD. Tensile testing indicated that the tensile modulus improved gradually with increasing modified-CNC content, whereas the elongation at fracture decreased.

Integration of thermoelectric generators with phase change materials (PCMs) is expected to be a promising technology for harvesting and converting waste heat to electricity, thus alleviating energy shortage and ecological damage. However, the low output electricity and inherent hardness of PCMs have limited their wide application. Herein, a multifunctional phase-change organohydrogel filled with paraffin wax (PW) microspheres is prepared using Pickering emulsion technology and UV-initiated polymerization. The PW was encapsulated in cellulose nanofibril (CNF)–MXene–Fe₃O₄ hybrid shells and then inlaid into a flexible polyacrylamide (PAAm) matrix. This unique structural feature provides enhanced thermoelectric conversion, superior shape stability, and excellent mechanical properties. The resultant organohydrogel can continuously harvest waste heat, transfer it into a thermoelectric generation system, and output electrical energy. The generated output voltage and power can reach 627.0 mV and 65.7 mW, respectively. The thermoelectric generator also exhibited good thermal cycling stability (for more than 50 cycles). Besides, the composite organohydrogel possesses satisfactory thermosensing capacity to monitor real-time temperature variation and hot steam behavior. This work opens up opportunities for highly efficient conversion of waste heat to electricity.

Antimony sulfide (Sb2S3) has been applied in photoelectric devices for a long time. However, there was lack of information about Sb2S3 quantum dots (QDs) because of the synthesis difficulties. To fill this vacancy, water-soluble Sb2S3 QDs were prepared by hot injection using hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) mixture as anionic-cationic surfactant, alkanol amide (DEA) as stabilizer, and ethylenediaminetetraacetic acid (EDTA) as dispersant. Photoelectric properties including absorbing and emission were characterized by UV-Vis-IR spectrophotometer and photoluminescence (PL) spectroscopic technique. An intensive PL emission at 880 nm was found, indicating Sb2S3 QDs have good prospects in near-infrared LED and near-infrared laser application. Sb2S3 QD thin films were prepared by self-assembly growth and then annealed in argon or selenium vapor. Their band gaps (E g s) were calculated according to transmittance spectra. The E g of Sb2S3 QD thin film has been found to be tunable from 1.82 to 1.09 eV via annealing or selenylation, demonstrating the good prospects in photovoltaic application.