Structural and Optical Characteristics of TiO₂Nanoparticles-Containing Mesoporous Silica (SBA-15) Thin Films

Atomic Layer Deposited (ALD) TiO2 on Fibrous Nano-Silica (KCC-1) for Photocatalysis: Nanoparticle Formation and Size Quantization Effect

“…In the case of heated samples, the band at 202–230 nm was very weak, indicating the presence of very few tetrahedral Ti sites, and most of them converted into octahedral Ti sites (Figure d). We also observed a red shift in the band at 250–370 nm with an increase in ALD cycles, which may be due to the formation of larger nanoparticles at higher ALD cycles, forming Ti sites with increased coordination numbers. ,, …”

“…Interestingly, after heat treatment at 700 °C, we observed the formation of small and monodispersed TiO 2 nanoparticles (NPs) of these ALD coated samples of KCC-1 (Figure ). − Heat treatment fragmented the amorphous TiO 2 layers, and crystalline NPs were formed. A detailed investigation of the NP size and dispersion was performed using STEM analysis.…”

“…We also observed a red shift in the band at 250−370 nm with an increase in ALD cycles, which may be due to the formation of larger nanoparticles at higher ALD cycles, forming Ti sites with increased coordination numbers. 57,72,73 To study the change in band gap of these KCC-1-based materials, we analyzed them using UV-DRS. Band gap measurement using Tauc plots suggested that there is an indirect band gap present in all of these materials (Figure 5e,f).…”

Synthesis of uniformly dispersed anatase nanoparticles inside mesoporous silica thin films via controlled breakup and crystallization of amorphous TiO2 deposited using atomic layer deposition

“…15 In many photoactive mesoporous silica thin lms, the TiO 2 nanoparticles are part of the mixed titania-silica matrix composing the walls of the porous structures. [19][20][21][22][23][24][25][26][27] Free standing silica lms containing titania nanoparticles of less than 10 nm were synthesized via co-condensation of Ti and Si precursors in the presence of a structure directing polymer followed by evaporation induced self assembly. [19][20][21][22] Similar thin lms supported on substrates with TiO 2 nanocrystals of 5-15 nm were obtained by a strategy in which a suspension of preformed colloidal titania nanoparticles mixed with silica precursor and polymeric templates were spin coated or dip coated on substrates, followed by thermal treatment.…”

“…In two reports the creation of nanosized TiO 2 crystals inside the pores of hexagonally ordered mesoporous lms was achieved by impregnation of the Ti precursor in the mesoporous silica followed by thermal treatment. 26,27 Atomic layer deposition is a thin lm deposition technique which can be used as a post synthesis modication for mesoporous materials for tailoring the internal surface. 28 The capabilities of ALD in creating heterostructured materials with interesting energy and environmental applications including photocatalysis are highly appreciated.…”