Additive effect of phosphoric acid on phosphorus-containing mesoporous silica film formation

Transparent phosphorous-containing mesoporous silica films were successfully synthesized by two different processes using the phosphoric acid addition before and after the sol–gel based mesopore formation. In the X-ray diffraction patterns, the films prepared by the addition before the formation exhibited highly-ordered pore channels with a hexagonal structure parallel to a substrate surface, while those after the formation have the larger pores with worm-like structures. Therefore, the highly- and randomly-ordered nanostructures were prepared by the phosphoric acid additive processes before and after the mesopore formation, suggesting the doping inside the silica frameworks and the composite outside the silica mesopores, respectively. [Display omitted] •Preparation of phosphorous-containing mesoporous silica films were investigated.•The interaction between phosphoric acid and silica species were clarified.•The phosphorous-incorporated amount and mesostructures were controlled.