By transforming chitin into a highly porous aerogel and subsequently carbonizing it, the researchers created an interconnected carbon framework capable of stabilizing molten phase change materials while maintaining high thermal storage capacity.
Latent heat storage using PCMs is widely regarded as a key technology for improving energy efficiency, especially in buildings, electronics cooling, and low-temperature thermal storage. While organic PCMs outperform many alternatives in safety and stability, leakage during melting remains a universal challenge. One promising strategy is to embed PCMs into porous solid supports, creating so-called shape-stabilized PCMs that rely on capillary forces and interfacial interactions to hold the liquid in place. Yet many existing supports—such as expanded graphite or metal–organic frameworks—are costly, energy-intensive to produce, or environmentally unsustainable. Biomass-derived carbon materials offer a greener alternative, but conventional structures often lack the pore architecture needed to hold large amounts of PCM without leakage.
A study (DOI: 10.48130/scm-0025-0010) published in Sustainable Carbon Materialson 29 December 2025 by Hui Li’s team, Shandong Jianzhu University, demonstrates that biomass-derived chitin carbon aerogels can simultaneously achieve leak-free stabilization, high thermal storage density, and long-term reliability in organic phase change materials, providing a sustainable and scalable solution for advanced thermal energy storage and thermal management applications.
The study first employed a systematic materials‐engineering and characterization approach to evaluate the thermal storage behavior of SA stabilized within chitin‐derived carbon aerogels (SA/CAX). Differential scanning calorimetry (DSC) was used to probe phase change temperatures, enthalpy, and supercooling behavior; thermal conductivity measurements assessed heat transfer efficiency; heating tests quantified leakage resistance; nitrogen adsorption–desorption, mercury intrusion porosimetry, SEM, FTIR, and XRD were applied to resolve pore architecture, morphology, and interfacial interactions; kinetic parameters were extracted using Kissinger analysis; and long‐term reliability was examined through repeated thermal cycling. These methods collectively revealed that encapsulating SA within CAX significantly modifies its thermal behavior. Compared with pure SA, SA/CAX exhibited slightly reduced melting temperatures and elevated freezing temperatures, leading to a markedly lower supercooling degree (<1.48 °C), which is attributed to enhanced heterogeneous nucleation enabled by the aerogel’s interconnected pore network. Although the measured phase change enthalpy of SA/CAX was lower than its theoretical value due to confinement effects, increasing the carbonization temperature weakened SA–support interactions and raised the melting enthalpy from 117.66 to 125.42 J g⁻¹. Thermal conductivity increased substantially from 0.180 W m⁻¹ K⁻¹ for pure SA to 0.291–0.439 W m⁻¹ K⁻¹ for SA/CAX, reflecting improved heat transport through graphitized carbon pathways. Heating tests showed that SA/CA500 achieved complete leakage suppression, whereas higher carbonization temperatures caused pore collapse and increased leakage. Comparative analysis demonstrated that SA/CA500 outperformed SA/CN500 by combining high enthalpy, superior shape stability, and enhanced thermal conductivity. Structural characterization confirmed that CA500 possesses large, interconnected macropores that accommodate SA molecules effectively, while nitrogen‐doped surfaces induce hydrogen bonding that further stabilizes the PCM. Kinetic analysis showed that CA500 increased the activation energy of SA from 347.5 to 442.6 kJ mol⁻¹, indicating improved thermal stability. Finally, SA/CA500 retained its phase change temperature and lost only ~3% enthalpy after 100 thermal cycles, demonstrating excellent cycling durability and suitability for practical thermal energy storage.
This leak-free, high-capacity thermal storage material opens new opportunities for sustainable energy technologies. Potential applications include thermal regulation in buildings, waste-heat recovery systems, solar energy storage, and thermal management of electronic devices. By using chitin—a renewable, widely available biomass—the approach also adds value to biological waste streams and reduces reliance on expensive or environmentally burdensome materials.
