Highly efficient CoOx/SBA-15 catalysts prepared by atomic layer deposition for the epoxidation reaction of styrene
Abstract
Co-based catalysts have been widely studied for the epoxidation reaction of styrene. Herein, we directly introduced CoOx species into SBA-15 by atomic layer deposition (ALD). The CoOx/SBA-15 catalysts exhibit remarkably higher activity and selectivity in epoxidation of styrene than the catalyst prepared by incipient wetness impregnation. This is due to the fact that CoOx nanoclusters were produced by ALD and uniformly dispersed in SBA-15. Furthermore, before the CoOx ALD process, an ultrathin TiO2 layer was coated onto SBA-15 firstly by ALD to modify the active species–support interaction precisely. The obtained catalysts show improved selectivity and stability compared to the unmodified catalysts. This is due to the appropriate interaction between the CoOx and support.