Metal-Organic Frameworks for Ammonia-Based Thermal Energy Storage
Guoliang An1, Xiaoxiao Xia2, Shaofei Wu1
1Institute of Refrigeration and Cryogenics, Key Laboratory of Power Machinery and Engineering of MOE, Shanghai Jiao Tong University, Shanghai, 200240, China.
Small (Weinheim an Der Bergstrasse, Germany)
|September 23, 2021
Summary
Metal-organic frameworks (MOFs) show promise for thermal energy storage. MIL-101(Cr)-ammonia pairs offer high capacity and stability, outperforming water pairs for efficient energy storage.
Area of Science:
- Materials Science
- Chemical Engineering
- Energy Storage
Background:
- Metal-organic frameworks (MOFs) are increasingly explored for thermal energy storage applications.
- MOF-ammonia systems have potential for thermal energy storage, but require experimental validation.
Purpose of the Study:
- To experimentally assess the feasibility of seven MOF-ammonia working pairs for thermal energy storage.
- To identify MOF-ammonia pairs with high sorption stability, capacity, and energy storage density.
Main Methods:
- Ammonia sorption stability and thermodynamics of seven MOF-ammonia pairs were evaluated.
- MIL-101(Cr) and ZIF-8(Zn) were tested under specific condensation/evaporation temperatures (30 °C/10 °C).
- Sorption capacity, stability, hysteresis, thermal energy storage density, and coefficient of performance were analyzed.
Main Results:
- MIL-101(Cr) demonstrated high ammonia sorption stability and the highest sorption capacity (≈0.76 g g-1).
- The MIL-101(Cr)-ammonia pair showed over three times higher sorption capacity than the MIL-101(Cr)-water pair at temperatures below 8.4 °C.
- MIL-101(Cr)-based systems exhibited superior thermal energy storage density (>1200 kJ kg-1) and coefficient of performance compared to ZIF-8(Zn).
Conclusions:
- MIL-101(Cr) and ZIF-8(Zn) are promising MOF-ammonia working pairs for thermal energy storage.
- The MIL-101(Cr)-ammonia system is particularly effective for conditions requiring low evaporation and high condensation temperatures.
- This research supports the development of efficient and stable MOF-ammonia thermal energy storage systems.
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