Methanol adsorption on HKUST-1 coatings obtained by thermal gradient deposition (TGD)

Adsorption-driven heat transformation has been reported as one of the most promising areas to bring metal-organic frameworks (MOFs) into industrial application. The vast majority of evaluated systems apply water as the working fluid. Since the use of water comes with many drawbacks, short-chained alcohols have been proposed as an alternative working fluid. In this contribution, the working flow from adsorbent (HKUST-1) characterization up to technical application is presented. Beginning with the thorough characterization of the process of direct crystallization on different structures, the results of methanol adsorption measurements are presented. Coatings are evaluated by applying the Dubinin-Astakhov approach to describe adsorption data and to calculate a coefficient of performance (COP). The maximum methanol uptake of the coatings was approximately 0.6 gMeOH/gMOF, leading to a COP of 1.5 at given temperatures. With respect to the cyclic application, the stability of HKUST-1 and methanol has also been investigated.