Self-limited pore size reduction of mesoporous silica membranes via pyridine-catalyzed silicon dioxide ALD

The pore size of mesoporous silica membranes is reduced using pyridine-catalyzed SiO2 ALD within the mesoporous matrix. The use of pyridine to catalyze the ALD results in lowering the reaction temperature to 80 degreesC. It also self-limits the pore size reduction as shown in gas permeation experiments. The self-limiting aspect of the deposition, controlled by size exclusion of catalyst from the pore, has the potential of controlling the pore size within the membrane. The paper concludes that this technique may prove useful as a general technique for healing defects in membranes.