The Adsorption & Advanced Materials Laboratory (A2ML), Department of Chemical Engineering & Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge, CB3 0AS, UK.
Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and the Barcelona Institute of Science and Technology Campus UAB, Bellaterra, Barcelona, 08193, Spain.
Adv Mater. 2023 Jun;35(23):e2209104. doi: 10.1002/adma.202209104. Epub 2023 Apr 21.
Space cooling and heating, ventilation, and air conditioning (HVAC) accounts for roughly 10% of global electricity use and are responsible for ca. 1.13 gigatonnes of CO emissions annually. Adsorbent-based HVAC technologies have long been touted as an energy-efficient alternative to traditional refrigeration systems. However, thus far, no suitable adsorbents have been developed which overcome the drawbacks associated with traditional sorbent materials such as silica gels and zeolites. Metal-organic frameworks (MOFs) offer order-of-magnitude improvements in water adsorption and regeneration energy requirements. However, the deployment of MOFs in HVAC applications has been hampered by issues related to MOF powder processing. Herein, three high-density, shaped, monolithic MOFs (UiO-66, UiO-66-NH , and Zr-fumarate) with exceptional volumetric gas/vapor uptake are developed-solving previous issues in MOF-HVAC deployment. The monolithic structures across the mesoporous range are visualized using small-angle X-ray scattering and lattice-gas models, giving accurate predictions of adsorption characteristics of the monolithic materials. It is also demonstrated that a fragile MOF such as Zr-fumarate can be synthesized in monolithic form with a bulk density of 0.76 gcm without losing any adsorption performance, having a coefficient of performance (COP) of 0.71 with a low regeneration temperature (≤ 100 °C).
空间冷却和加热、通风和空调（HVAC）约占全球用电量的 10%，每年造成约 11.3 亿吨 CO 排放。基于吸附剂的 HVAC 技术长期以来一直被誉为传统制冷系统的节能替代品。然而，迄今为止，还没有开发出合适的吸附剂来克服与传统吸附材料（如硅胶和沸石）相关的缺点。金属-有机框架（MOFs）在水吸附和再生能源需求方面有数量级的提高。然而，MOF 在 HVAC 应用中的部署受到与 MOF 粉末处理相关的问题的阻碍。在此，开发了三种具有高密、成型、整体式 MOF（UiO-66、UiO-66-NH 和 Zr-富马酸盐），其具有出色的体积气体/蒸气吸收能力，解决了 MOF-HVAC 部署中的先前问题。使用小角 X 射线散射和格子气体模型可视化了介孔范围内的整体结构，对整体材料的吸附特性进行了准确预测。还证明了即使是脆弱的 MOF（如 Zr-富马酸盐）也可以以 0.76 gcm 的体密度整体合成，而不会损失任何吸附性能，其性能系数（COP）为 0.71，再生温度低（≤100°C）。
