Zirconium doped TiO2 nano-powder via halide free non-aqueous solvent controlled sol-gel route

Novel TiO2 Photocatalyst Using Nonaqueous Solvent- Controlled Sol-Gel Route

“…XRD peaks of crystal planes of Zr doped TiO 2 (Figure 2(A)) shows red shift in 2θ values, which confirms the substitutional doping of Zr 4+ at Ti 4+ site [10]. The substitutional doping of Zr in TiO 2 results in an increase in cell parameter and cell volume as reported by Yu et al [68] and Wang et al [69] Thus, incorporation of large sized Zr results in lattice strain and hence leads to formation of oxygen vacancies and suppresses the grain growth.…”

“…Xie et al [65] who used aqueous sol-gel synthesis, reported that large size Na cannot substitute Ti and therefore migrates to TiO 2 surface forming Na-O bonds as there is no peak shift is observed in XRD patterns. Thus it appears that substitutional doping of Na at Ti in TiO 2 , as indicated by the XRD peak shifts in Figure 2(B), is facilitated by nonaqueous solvent controlled sol-gel route, which was used by Singh et al [10].…”

“…Also, pristine TiO 2 suffers from higher recombination rate of charge carriers (electron and hole) resulting in less photocatalytic efficiency. Metals [10,[47][48][49][50][51][52] and nonmetals [53][54][55][56][57][58] are well known for their ability to reduce the band gap of TiO 2 by generating energy states between valence band and conduction band. These energy states serve as charge carrier trapping center and therefore reduce the electron hole recombination rate.…”

“…In both, Zr doped TiO 2 and Na doped TiO 2 , the crystallite size reduces for certain dopant concentration and hence increases the surface area of nanoparticles. Additionally, A-R phase transformation temperature is increased due to doping Zr 4+ and Na +1 in TiO 2 matrix [10,65,68,69].…”

“…Metal oxide nanoparticles (MONPs) are well-known for their outstanding role especially for environmental, sensor, biomedical and energy applications [1][2][3][4][5][6][7][8][9][10]. Among MONPs, TiO 2 nanoparticles are least toxic [11] and therefore synthesis of nanostructured TiO 2 with tailored properties has been most extensively investigated in recent years.TiO 2 occurs in three different phases [12], anatase, rutile and brookite with rutile as most stable phase and anatase as most desirable phase.…”