可调节的低压水吸附在稳定的多变体金属有机框架中,以促进以水为基础的超低温驱动制冷
Chen-Han Guo1, Feng-Fan Lu1, Enyu Wu1
1State Key Laboratory of Silicon and Advanced Semiconductor Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|January 15, 2024
概括
新的多变体金属有机框架 (MTV-MOFs) 显著提高了近零碳吸附制冷的水吸收. 这一突破提高了低温的冷却效率,提供了一个有前途的绿色冷却解决方案.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 可持续能源 可持续能源
背景情况:
- 使用水作为制冷剂的吸附制冷是接近零碳冷却的关键策略.
- 现有的金属有机框架 (MOFs) 通常显示在P/P0 = 0.2以下的水吸收量有限,阻碍了冷却性能.
- 改善低压水吸收对于提高制冷中的性能系数 (COP) 至关重要.
研究的目的:
- 开发多变量MOF (MTV-MOF),增强低压水吸收,以改善制冷.
- 通过修改MIL-125-NH2结构来设计和合成新的MTV-MOF.
- 评估这些MTV-MOF在水基吸附制冷系统中的性能.
主要方法:
- 配合物交换被用来修改原始的MIL-125-NH2 MOF,创建带有裸体位的MTV-MOF.
- 在298K和不同相对压力 (P/P0) 测量了吸水能力.
- 在65°C的超低驱动温度下,评估了吸附制冷性能,包括COP和工作能力.
主要成果:
- 合成的MIL-125-NH2 / MD-5%呈现出显著增强的水吸收0.39 g g-1在P/P0 = 0.2,比原始的MOF高三倍.
- 这种MTV-MOF的吸水量与KMF-1和MIP-200等基准材料的吸水量相当.
- MIL-125-NH2/MD-5%实现了0.8的高COP和0.24gg-1的工作能力,在超低驱动温度下表现优于其他MOF.
结论:
- 开发的MTV-MOF,特别是MIL-125-NH2 / MD-5%,有效地提高了吸附制冷的低压水吸收.
- 这些材料提供了出色的稳定性,快速吸附动力学和低温再生能力.
- MIL-125-NH2/MD-5% 是一种高效的吸附剂,用于实际的超低温驱动绿色冷却应用.
相关概念视频
01:23States of Water
Water exists in any one of the three classical states: solid (ice), liquid (water), and gas (steam or water vapor). The state of water depends on i) the intermolecular forces that draw molecules together and ii) the kinetic energy that leads to movements that pull them apart.
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
03:28Vapor Pressure Lowering
The equilibrium vapor pressure of a liquid is the pressure exerted by its gaseous phase when vaporization and condensation are occurring at equal rates: Dissolving a nonvolatile substance in volatile liquid results in a lowering of the liquid’s vapor pressure. This phenomenon can be explained by considering the effect of added solute molecules on the liquid's vaporization and condensation processes. To vaporize, solvent molecules must be present at the surface of the solution. The presence of...
03:12Freezing Point Depression and Boiling Point Elevation
Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...