Highly efficient CoO_x/SBA-15 catalysts prepared by atomic layer deposition for the epoxidation reaction of styrene

Co-based catalysts have been widely studied for the epoxidation reaction of styrene. Herein, we directly introduced CoO_x species into SBA-15 by atomic layer deposition (ALD). The CoO_x/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 CoO_x nanoclusters were produced by ALD and uniformly dispersed in SBA-15. Furthermore, before the CoO_x 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 CoO_x and support.