Abstract
The phase change materials (PCMs) used in medium-temperature thermal energy storage can store and release a large amount of latent heat. However, their use in real-world applications is often limited by poor thermal conductivity and degradation stability during repeated heating cycles. Therefore, improving the thermal reliability and kinetic behaviour of PCMs is essential for advancing high-performance energy storage systems. This research assessed the thermal stability and degradation kinetics of pure D-mannitol and its graphene nanoplatelet (GNP)-reinforced composites. It introduced a new combination of model-free kinetic modelling and machine-learning-based predictions for evaluating the thermal reliability of nano-enhanced PCMs. Five different PCM compositions (containing 0, 0.25, 0.5, 0.75, and 1 wt% GNP) were prepared using ultrasonic-assisted dispersion. Non-isothermal thermogravimetric analysis (TGA) was performed at five different heating rates (10–25 °C·min⁻¹), and the activation energies (Eₐ) were determined using the Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), and Starink model-free methods. The Starink model yielded the lowest Eₐ for pure D-mannitol (61.99 kJ·mol⁻¹ at α ≈ 0.1), while the KAS and FWO models provided mean values of 137.62 kJ·mol⁻¹ and 141.48 kJ·mol⁻¹, respectively. Incorporating GNP improved thermal stability across all compositions, with Eₐ ranging from 123.67 to 149.08 kJ·mol⁻¹. The random forest regression model achieved the best predictive accuracy (R² = 0.99, RMSE = 0.0002), outperforming both linear and polynomial models. Overall, the addition of graphene nanoplatelets significantly enhances both chemical and thermal stability, confirming their role as effective nano-additives for PCM improvement and enabling the design of thermally stable “smart” energy storage systems for solar and sustainable applications. The thermal stability of Graphene Nanoplatelets (GNP)-enhanced D-Mannitol was determined through non-isothermal TGA analysis at heating rates between 10–25 °C min-1. The decomposition behaviour of the GNP-enhanced D-Man was characterized using Model-Free Kinetic Methods and Machine Learning Models to determine the accuracy of predicting the thermal stability of the D-Man using the most significant thermal parameters.
Keywords
D-Mannitol, Graphene Nano platelets, Thermal Decomposition, Activation Energy, Machine learning,Downloads
References
- L.E.A. Wijkhuijs, P. Schmit, I. Schreur-Piet, H. Huinink, R. Tuinier, H. Friedrich, Graphene nanoplatelet distribution governs thermal conductivity and stability of Paraffin-Based PCMs. Nanomaterials, 15(8), (2025) 587. https://doi.org/10.3390/nano15080587
- Z. Said, A. Pandey, A.K. Tiwari, B. Kalidasan, F. Jamil, A.K. Thakur, V. Tyagi, A. Sarı, H.M. Ali, Nano-enhanced phase change materials: Fundamentals and applications. Progress in Energy and Combustion Science, 104, (2024) 101162. https://doi.org/10.1016/j.pecs.2024.101162
- L. Yang, N. Zhang, Y. Yuan, X. Cao, B. Xiang, Thermal performance of stearic acid/carbon nanotube composite phase change materials for energy storage prepared by ball milling. International Journal of Energy Research, 43(12), (2018) 6327–6336. https://doi.org/10.1002/er.4352
- A. Shama, A.E. Kabeel, B.M. Moharram, H.F. Abosheiasha, Improvement of the thermal properties of paraffin wax using high conductive nanomaterial to appropriate the solar thermal applications. Applied Nanoscience, 11(7), (2021) 2033–2042. https://doi.org/10.1007/s13204-021-01903-7
- M. Aqib, A. Hussain, H.M. Ali, A. Naseer, F. Jamil, Experimental case studies of the effect of Al2O3 and MWCNTs nanoparticles on heating and cooling of PCM. Case Studies in Thermal Engineering, 22, (2020) 100753. https://doi.org/10.1016/j.csite.2020.100753
- L. Zhang, P. Zhang, F. Wang, M. Kang, R. Li, Y. Mou, Y. Huang, Phase change materials based on polyethylene glycol supported by graphene-based mesoporous silica sheets. Applied Thermal Engineering, 101, (2016) 217–223. https://doi.org/10.1016/j.applthermaleng.2016.02.120
- R.K. Kottala, B.K. Chigilipalli, S. Mukuloth, R. Shanmugam, V.C. Kantumuchu, S.B. Ainapurapu, M. Cheepu, Thermal degradation studies and machine learning modelling of Nano-Enhanced Sugar Alcohol-Based phase change materials for medium temperature applications. Energies, 16(5), (2023) 2187. https://doi.org/10.3390/en16052187
- L. Sun, Y. Qu, S. Li, Co-microencapsulate of ammonium polyphosphate and pentaerythritol and kinetics of its thermal degradation. Polymer Degradation and Stability, 97(3) (2011) 404–409. https://doi.org/10.1016/j.polymdegradstab.2011.12.003
- A.J. Otaru, Kinetics study of the thermal decomposition of date seed powder/HDPE plastic blends. Bioresource Technology Reports, 29, (2025) 102028. https://doi.org/10.1016/j.biteb.2025.102028
- K.P. Venkitaraj, S. Suresh, Experimental thermal degradation analysis of pentaerythritol with alumina nano additives for thermal energy storage application. Journal of Energy Storage, 22, (2019) 8–16. https://doi.org/10.1016/j.est.2019.01.017
- L. Xiang, D. Luo, J. Yang, X. Sun, Y. Qi, S. Qin, Preparation and Comparison of Properties of Three Phase Change Energy Storage Materials with Hollow Fiber Membrane as the Supporting Carrier. Polymers, 11(8), (2019) 1343. https://doi.org/10.3390/polym11081343
- T. Ahmad, H. Chen, Y. Guo, J. Wang, A comprehensive overview on the data driven and large scale based approaches for forecasting of building energy demand: A review. Energy and Buildings, 165, (2018) 301–320. https://doi.org/10.1016/j.enbuild.2018.01.017
- D.K. Bhamare, P. Saikia, M.K. Rathod, D. Rakshit, J. Banerjee, A machine learning and deep learning based approach to predict the thermal performance of phase change material integrated building envelope. Building and Environment, 199, (2021) 107927. https://doi.org/10.1016/j.buildenv.2021.107927
- A. Basem, H.K. Abdulaali, A. Alizadeh, P.K. Singh, K. Parashar, A.E. Anqi, H. Rajab, P. Cajla, H. Maleki, Integrating artificial Intelligence-Based metaheuristic optimization with Machine learning to enhance Nanomaterial-Containing latent heat thermal energy storage systems. Energy Conversion and Management X, 25, (2025) 100835. https://doi.org/10.1016/j.ecmx.2024.100835
- R. Jia, K. Sun, R. Li, Y. Zhang, W. Wang, H. Yin, D. Fang, Q. Shi, Z. Tan, Heat capacities of some sugar alcohols as phase change materials for thermal energy storage applications. The Journal of Chemical Thermodynamics, 115, (2017) 233–248. https://doi.org/10.1016/j.jct.2017.08.004
- T. Wu, N. Xie, J. Niu, J. Luo, X. Gao, Y. Fang, Z. Zhang, Preparation of a low-temperature nanofluid phase change material: MgCl2–H2O eutectic salt solution system with multi-walled carbon nanotubes (MWCNTs). International Journal of Refrigeration, 113, (2020) 136–144. https://doi.org/10.1016/j.ijrefrig.2020.02.008
- R.P. Singh, S. Kaushik, D. Rakshit, Melting phenomenon in a finned thermal storage system with graphene nano-plates for medium temperature applications. Energy Conversion and Management, 163, (2018) 86–99. https://doi.org/10.1016/j.enconman.2018.02.053
- B. Dong, C. Cao, S.E. Lee, Applying support vector machines to predict building energy consumption in tropical region. Energy and Buildings, 37(5), (2004) 545–553. https://doi.org/10.1016/j.enbuild.2004.09.009
- L. Wei, W. Tian, E.A. Silva, R. Choudhary, Q. Meng, S. Yang, Comparative Study on Machine Learning for Urban Building Energy Analysis. Procedia Engineering, 121, (2015) 285–292. https://doi.org/10.1016/j.proeng.2015.08.1070
- H. Bagheri-Esfeh, H. Safikhani, S. Motahar, Multi-objective optimization of cooling and heating loads in residential buildings integrated with phase change materials using the artificial neural network and genetic algorithm. Journal of Energy Storage, 32, (2020) 101772. https://doi.org/10.1016/j.est.2020.101772
- Y. Lin, W. Yang, Application of Multi-Objective Genetic Algorithm Based Simulation for Cost-Effective Building Energy Efficiency Design and Thermal Comfort Improvement. Frontiers in Energy Research, 6, (2018) 25. https://doi.org/10.3389/fenrg.2018.00025
- X. Xiao, Q. Hu, H. Jiao, Y. Wang, A. Badiei, Simulation and machine learning investigation on thermoregulation performance of phase change walls. Sustainability, 15(14), (2023) 11365. https://doi.org/10.3390/su151411365
- L.G. Socaciu, P.V. Unguresan, Using the Analytic Hierarchy Process to Prioritize and Select Phase Change Materials for Comfort Application in Buildings. Scientific Journal. Series Mathematical Modelling in Civil Engineering, 10(1), (2014) 21–28. https://doi.org/10.2478/mmce-2014-0003
- P. Erdinç, Z. Buduneli, Ç. Gerşil, C. Erton, M. Paldrak, E. Staiou, (2024). Analytic Hierarchy Process (AHP) and Goal Programming Approach for a Real-Life Supplier Selection Problem. In Lecture notes in mechanical engineering, Springer. https://doi.org/10.1007/978-3-031-53991-6_53
- F. Nurprihatin, R. Antonius, G.D. Rembulan, R. Djajasoepena, E. Sulistyo, Analytical Hierarchy Process And Topsis Approach To Perform Supplier Selection In Construction Industry. Jiems (Journal of Industrial Engineering and Management Systems), 15(2), (2023). https://doi.org/10.30813/jiems.v15i2.4124
- F.M. Monticeli, R.M. Neves, H.L.O. Júnior, Using an artificial neural network (ANN) for prediction of thermal degradation from kinetics parameters of vegetable fibers. Cellulose, 28(4), (2021) 1961–1971. https://doi.org/10.1007/s10570-021-03684-2
- J.P. Martin, B.J. Rasor, J. DeBonis, A.S. Karim, M.C. Jewett, K.E. Tyo, L.J. Broadbelt, A dynamic kinetic model captures cell-free metabolism for improved butanol production. Metabolic Engineering, 76, (2023) 133–145. https://doi.org/10.1016/j.ymben.2023.01.009
- N.A. Van Riel, Dynamic modelling and analysis of biochemical networks: mechanism-based models and model-based experiments. Briefings in Bioinformatics, 7(4), (2006) 364–374. https://doi.org/10.1093/bib/bbl040
- K. Patidar, A. Singathia, M. Vashishtha, V. Kumar Sangal, S. Upadhyaya, Investigation of kinetic and thermodynamic parameters approaches to non-isothermal pyrolysis of mustard stalk using model-free and master plots methods. Materials Science for Energy Technologies, 5, (2022) 6-14. https://doi.org/10.1016/j.mset.2021.11.001
- E. Tarani, K. Chrissafis, Isoconversional methods: A powerful tool for kinetic analysis and the identification of experimental data quality. Thermochimica Acta, 733, (2024) 179690. https://doi.org/10.1016/j.tca.2024.179690
- L. Feng, J. Zheng, H. Yang, Y. Guo, W. Li, X. Li, Preparation and characterization of polyethylene glycol/active carbon composites as shape-stabilized phase change materials. Solar Energy Materials and Solar Cells, 95(2), (2011) 644-650. https://doi.org/10.1016/j.solmat.2010.09.033
- I.A. Laghari, M. Samykano, A. Pandey, Z. Said, K. Kadirgma, V. Tyagi, (2022). Thermal conductivity and Thermal properties enhancement of Paraffin/ Titanium Oxide based Nano enhanced Phase change materials for Energy storage. 2022 Advances in Science and Engineering Technology International Conferences (ASET), IEEE, Dubai, United Arab Emirates. https://doi.org/10.1109/aset53988.2022.9735037
- B.S. Jinshah, R.K. Kottala, K.R. Balasubramanian, A. Francis, Experimental analysis of phase change material integrated single phase natural circulation loop. Materials Today: Proceedings, 46, (2021) 10000-10005. https://doi.org/10.1016/j.matpr.2021.04.251
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