Influence of calcination temperature on the physicochemical properties of atomic/molecular layer deposited hybrid inorganic/organic ceramic nanofiltration membranes

Post-deposition calcination in the air of hybrid inorganic/organic layers is considered to remove the organic constituents and completely create a full inorganic membrane. This study aims to investigate to what extent such a removal occurs and the effect of remaining organic constituents on the physicochemical properties of the membrane layer. Three hybrid layers were deposited using trimethylaluminum, two aliphatic- (ethylene glycol and 1,6-hexanediol) and one aromatic alcohol (hydroquinone). The effects of the different calcination treatments on the physicochemical properties were investigated. Differential thermogravimetric analysis established that the maximum mass loss rate temperatures for the hybrid layers grown from the aliphatic alcohols are lower than those from the aromatic co-reactant. After 250 degrees C, water contact angles (WCAs) were between 46 degrees - 92 degrees and IR spectroscopy and XPS showed the presence of carbon. Calcination at 350 degrees C reduced the WCA to 0 degrees - 25 degrees and decreased carbon content.