Improved Ethanol Adsorption Capacity and Coefficient of Performance for Adsorption Chillers of Cu-BTC@GO Composite Prepared by Rapid Room Temperature Synthesis

A composite of Cu-BTC and graphite oxide (GO) was prepared by rapid room-temperature synthesis method for thermally driven adsorption chillers (TDCs). A series of composites Cu-BTC@GO with varied GO loading were synthesized at room temperature within 1 min, and characterized by N₂ adsorption test, scanning electron microscopy, powder X-ray diffraction, and Fourier transform infrared analysis. The adsorption isotherms of ethanol on the composites were measured at different temperatures, and then, the isosteric heats of ethanol adsorption were estimated. The composite working capacities and coefficient of performance (COP) of the composite–ethanol working pair were calculated for the application of refrigeration. Results showed that Cu-BTC@GO possessed a superhigh adsorption capacity for ethanol up to 13.60 mmol/g at 303 K, which was attributed to introduction of GO leading to increases in the surface dispersive forces and the mesoporous volume of Cu-BTC@GO. The isosteric heat of ethanol adsorption on Cu-BTC@GO was slightly higher than that of Cu-BTC. The adsorption capacity of Cu-BTC@GO was higher than many other metal–organic frameworks (MOFs) under the application conditions of TDCs. The composites exhibited 5.8–17.4% higher working capacity and energy efficiency than parent Cu-BTC for the application of refrigeration. The rapid room-temperature synthesis approach has potential for the preparation of new MOF-based composites.