Experimental Study on the Influence of Metal Doping on Thermophysical Properties of Porous Aluminum Fumarate

Metal-organic frameworks (MOFs) are emerging as potential adsorbents for adsorption based systems intended for various applications. Aluminum fumarate is one of the promising MOFs for being used as an adsorbent for water-based adsorption heat pumps. Though there have been a lot of studies regarding water adsorption characterization of aluminum fumarate, there is hardly any literature addressing the thermophysical properties. A green synthesis process is developed to enhance the thermophysical properties of MOFs. Transition metals (Nickel and Cobalt) are doped with parent aluminum fumarate at different weight percentage (5 wt%, 10 wt% and 20 wt%) during the synthesis. We measured and compared the specific heat capacity and thermal conductivity of parent aluminum fumarate and the six other modified samples. The current study shows that the specific heat capacity decreases whereas the thermal conductivity increases in accordance with the doping concentration. Among the studied samples, 20 wt% Cobalt-doped aluminum fumarate is found to have the lowest specific heat capacity and the highest thermal conductivity. These findings are crucial for the design and performance prediction of adsorption heat pumps.