Design of hybridized network structure and photoelectric thermal conversion performance of polyethylene glycol-based phase change composites

PEG60-polylactic acid (PLA40)-CNT0.6-X(y) phase-change energy storage composites were prepared in this paper by physically hybridizing carbon nanotubes (CNT) with BN, Al2O3, and copper powder (Cu), respectively, to investigate the effects of nanoparticles with different structures on the shape stability and photovoltaic conversion efficiency of polyethylene glycol (PEG) based phase-change composites. The incorporation of Al2O3 and Cu nano-fillers has a minor effect on the electrical conductivity of the PEG-PLA-CNT-X(y) composites. However, the introduction of BN drastically reduces the electrical conductivity of the composites. When the mass ratio of BN reaches 40%, the electrical conductivity of the PEG60-PLA40-CNT0.6-BN(40) composites is only 8.71×10−7 S/m, indicating obvious insulating properties. The spherical Al2O3 nanoparticles were found to be uniformly distributed inside the composites by SEM and EDS energy spectroscopy, and the thermal conductivity and enhancement factor (Φ) values of PEG60-PLA40-CNT0.6-Al2O3(40) composites were as high as 5.81 W/(m·K) and 363.6%, respectively. Compared to the PEG60-PLA40-CNT0.6 composites, the addition of Al2O3 improves the photothermal conversion efficiency (η), photo sensitive response rate, and current stability of PEG60-PLA40-CNT0.6-Al2O3(40) composites, raising the value from 42.9% to 79.9%. Moreover, composite materials exhibit higher sensitivity to light, faster response time, smoother current change curves, and excellent photoelectric conversion performance. © 2024 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.