Novel composite phase change materials based on hollow carbon nanospheres supporting fatty amines with high light-to-thermal transition efficiency

The construction of high-performance materials with superior light-to-thermal conversion efficiency is of great importance for harvesting and utilization of solar energy. Hence, we report the creation of novel composite phase change materials (CPCMs) CPCMs by incorporating three kinds of organic phase change materials (PCMs), i.e. 1-Tetradecylamine (TDA), 1-hexadecanamine (HDA) and Octadecylamine (ODA), into hollow carbon nanospheres (HCNS) via a simple impregnation treatment for efficient light-to-thermal transition. Owing to their carbon in nature, the HCNS show better light absorption of higher than 90%. After incorporation of organic PCMs, their light absorption could still attain 62–70%, which can compete with the existing CPCMs. Beneficial from their abundant porosity and high specific surface areas, organic PCMs can be spontaneously diffused and immersed into the porous architecture of HCNS. In this way, the as-resulted CPCMs containing with TDA, HDA and ODA show high phase change enthalpy of 61.23J/g, 119.5J/g and 101.8J/g, respectively. The CPCMs also exhibit better thermal conductivity and excellent thermal stability, e.g., the enthalpy of HAD based CPCMs remains nearly unchanged even after 100 times of melting/freezing cycles. Under 1 sun irradiation, the light-to-thermal conversion efficiency of CPCMs containing with TDA, HDA and ODA were measured to be 73.04%, 74.46% and 71.74%, respectively, Thus showing great potential as a kind of promising photothermal conversion devices for solar or thermal energy storage applications. •A novel CPCMs was fabricated to improve light-to-thermal conversion efficiency.•The CPCMs can harvest and transfer visible light efficiently.•The CPCMs own excellent thermal stability and enhanced thermal conductivity.