Research on the Thermal Characteristics of NH2-MIL-125 (Ti)/Salt Composite Adsorption Material Open System: Low Temperature Adsorption and Storage for Solar Energy

Research Overview: According to the information published in Volume 310 of Solar Energy Materials and Solar Cells, authors N. Ferrigno, K. Johannes, P. Asinari, F. Kuznek, and others conducted an open system thermal characterization study on the composite material formed by NH₂– MIL-125 (Ti) and salts (CaCl₂, SrBr₂) for solar driven low-temperature adsorption and heat storage. This article was published on January 15, 2027. The research focuses on the adsorption and thermal storage behavior of metal organic framework NH₂– MIL-125 (Ti) combined with inorganic salts, and investigates its thermal properties under open system conditions. An open system means that materials directly exchange water vapor with the external atmosphere in the actual operating environment, which differs from closed testing conditions and has reference value for evaluating the performance of materials under real working conditions.

Material system and testing ideas

NH₂– MIL-125 (Ti) is a titanium based MOF material with amino modification, and its pore structure can provide sites for water molecule adsorption;

; CaCl₂and SrBr₂, as hygroscopic salts, can enhance the adsorption capacity of composite materials. Combining MOFs with salts is a technological approach for exploring high-energy density and low regeneration temperature materials in the field of adsorption thermal storage. The core of this study lies in the characterization method of thermal characteristics under the “open system”. Compared with a closed system, an open system is closer to the actual mass transfer conditions of the adsorption bed in a solar low-temperature adsorption thermal storage device, and the test results have more direct reference significance for material screening and system design. The article does not provide specific numerical performance data, so it is not yet possible to compare the thermal storage density or cycling stability of different salt composite formulations based on this.

Significance for the polymer additive industry

Adsorption thermal storage materials themselves belong to the category of inorganic and porous materials, but their engineering applications cannot be separated from supporting polymer materials.

. The sealing components, insulation layers, adsorption bed bonding and packaging materials in thermal storage devices are required to have weather resistance and stability due to long-term exposure to environments with water vapor and temperature fluctuations. In such scenarios, antioxidants and photostability systems can help packaging materials resist thermal oxidative aging and humid heat aging, extending the service life of components. From a broader perspective of new energy materials, there are similarities between the aging mechanisms faced by the peripheral polymer components of energy storage devices and photovoltaic backboards: both require exposure to ultraviolet radiation, humidity, and temperature fluctuations in outdoor environments. Photovoltaic backboards rely on weather resistant and stable formula systems to ensure long-term insulation and water resistance performance, and packaging materials for energy storage and adsorption heat storage devices also require similar stability design concepts. The open system thermal characterization method provided by this study also provides a methodological reference for evaluating the performance changes of packaging materials under wet hot alternating conditions. It should be pointed out that this study belongs to the basic characterization work of adsorption heat storage materials, and does not involve direct testing of polymer additive formulations or photovoltaic backboards and encapsulation films. For additive companies, their value lies more in indicating the demand direction for weather resistance and stability of supporting polymer materials in energy and heat storage scenarios, rather than providing directly applicable formula conclusions.

To be observed

The information in the original abstract is limited, and the specific boundary conditions for the adsorption capacity, thermal storage density, cyclic stability, and open system testing of composite materials have not been disclosed.

. Subsequent attention should be paid to the systematic data on salt content, composite ratio, and thermal characteristic parameters in the complete paper to determine the actual potential of this material system in solar low-temperature thermal storage.

Information source:Open-system thermal characterization of NH₂-MIL-125(Ti)/salt composites (CaCl₂, SrBr₂) for solar-driven low-temperature sorption heat storage， Organized by Herun Chemical.