Bartlomiej GAIDA1, Jan KONDRATOWICZ2, Samantha PIPER2, Anna CHROBOK1, Douglas MACFARLANE2, Karolina MATUSZEK2, Alina BRZECZEK-SZAFRAN1
1Silesian University of Technology, Faculty of Chemistry, Department of Organic Chemical Technology and Petrochemistry, Gliwice, Poland
2Monash University, School of Chemistry, Melbourne, Australia
Replacement of fossil fuels-based technologies for energy generation with sustainable energy sources is indispensable to lower the CO2 emission. Continuous development of solar and wind energy-harvesting technologies that suffer from the intermittent character, requires economic and efficient energy storage systems. In this regard phase change materials (PCMs) capable of reversibly storing and releasing thermal energy in the form of latent heat during the phase transitions can become an attractive solution. Depending on the transition temperature, PCMs might be used for various applications and energy generation scenarios [1].
The development of phase change materials (PCMs) that melt in the range of 100-220 °C can significantly contribute to the prevalence of energy storage from solar-thermal, or other forms of renewable heat. In this temperature range sugar alcohols such as mannitol, galactitol, and erythritol, reveal as promising materials with the highest energy-storage density among all organic compounds. However, supercooling, crystallization issues and poor stability under operating conditions excludes them from use as PCMs in the pure form [2].
Although, sugar derivatives are cheap, biodegradable and non-toxic, what makes them attractive precursors for development of advanced, sustainable materials. Up to date, different approaches have been used to tune and/or improve the properties of sugar alcohols such as formation of binary sugar alcohols eutectic mixtures, formation of composite materials based on sugar alcohols and polymers, porous carbonaceous material, zeolitic imidazolate frameworks (ZIFs), inorganic porous materials, addition of metal powders (Cu/Al), as well as sugar alcohols nanoencapsulation. An alternative strategy for the sugar alcohols’ thermal properties improvement is their chemical modification.
We synthesized various ionic compounds based on natural carbohydrate derivatives (methyl-α-?-glucopyranoside, ?-mannitol, tartaric acid) (Figure 1). Herein we present an insight into their thermal characteristics and corresponding molecular interactions, supported by a crystallographic study. We believe that the investigation of interactions between anions and cations (also via hydrogen bonding) strongly govern properties, which are crucial for potential PCMs (melting enthalpy, crystallizability). Ionic compounds and low melting organic salts were recently recognized as promising materials for solar energy storage, hence detailed study on these new PCM candidates may deliver valuable information for the future design of sustainable PCMs.
References:
[1] Matuszek K.; Kar M.; Pringle J. M.; MacFarlane D. R.; Chem. Rev. 2022, doi.org/10.1021/acs.chemrev.2c00407
[2] Matuszek, K.; Vijayaraghavan, R.; Forsyth, C. M.; Mahadevan, S.; Kar, M.; MacFarlane, D. R. ChemSusChem 2019, 12, 1–7.