Dodecylamine/Ti3C2-pectin form-stable phase change composites with enhanced light-to-thermal conversion and mechanical properties.

The development of high-performance form stable phase change materials (FSPCMs) with higher optical absorbance and phase change enthalpy is of great significance to building energy conservation. A kind of Ti 3 C 2 /pectin aerogels was prepared by self-assembly of pectin and MXene nanosheet (Ti 3 C 2) by solution blending method. These aerogels were directly dipped in the molten dodecylamine (DDA) as the phase change material. The results show that the PCM composites with 3 wt% Ti 3 C 2 have a phase change temperature of 25.47 °C (at which the human body feels comfortable), latent heat of phase change of 218.8 kJ kg−1, and thermal conductivity of 0.1817 W/(m K). The prepared FSPCMs have the characteristics of suitable phase change temperature, high latent heat, good melting/freezing cycle reliability, strong mechanical properties, significant photothermal energy conversion capacity (more than 92%), and good thermal insulation performance. Therefore, the corresponding pectin-based composites with better light absorption and mechanical properties are expected to have broad application prospects in energy conversion and building energy conservation. • Aerogels with enhanced mechanical properties were prepared by self-assembly of Ti3C2 and pectin. • The addition of Mxene effectively improved the solar-thermal conversion efficiency (92.6%) of composites. • The form-stable PCM composite has a phase change enthalpy of 196.3 kJ kg-1 (after 200 cycles). • The dodecylamine used in building energy storage has a suitable phase transition temperature (25.18 °C). [ABSTRACT FROM AUTHOR]