Solvent effect on nucleation-growth of titanium-oxo-alkoxy nanoparticles

Nucleation and growth of mixed vanadium-titanium oxo-alkoxy nanoparticles in sol-gel synthesis

“…(which corresponds to H-h * =0.8 in Fig. 4) TOA induction rate of 0.1 min -1 has been observed [14], while the extrapolation of our experimental data predicts the rate of ~10 -4 min -1 , which according to Eq. 2 results in a much smaller induction rate of ~0.006 min -1 in the experimental conditions with 2 times higher Ti precursor concentration (similar to that of VTOA).…”

“…This model has been later refined [12] and extended to zirconium oxo-alkoxy (ZOA) system [13]. The TOA nucleus size 2R=2.5 nm proposed in early studies has been later revised: 2R=3.2 nm [14], which has been independently supported by HRTEM analysis of the titania-based organic-inorganic hybrid materials [15].…”

Titanium phosphonate oxo-alkoxide “clusters”: solution stability and facile hydrolytic transformation into nano titania

“…The size of these "clusters" were dependent on the organic solvent used, being 5.2 nm and 3.8 nm for isopropanol and n-propanol, respectively, illustrating hydrolytic transformation into nuclei of oxide phases in contact with water. 51 The transformation from the oxo-alkoxide complex into the oxide phase is facilitated by the acidity of the replacing ligands. Fornasieri and co-workers reported the substitution of ethoxide ligands in the Ti 16 O 16 (OEt) 32 complex were more facile for protic ligands with lower pKa-values and lesser steric hindrance.…”

Memristive TiO2: Synthesis, Technologies, and Applications

“…In the classical concept of sol–gel, the phase purity, size, and shape of synthesized TiO 2 nanoparticles are considered in relation to the hydrolysis and condensation reactions, the reactivity and concentration of the precursor (titanium alkoxide or TiCl 4 ), the solvent type, and the temperature (Cargnello et al, 2014 ). In addition, the early-stage processes such as nucleation, crystal growth, and aggregation (Teychené et al, 2020 ) may play a crucial role in the sol–gel synthesis of TiO 2 nanoparticles (Cheng et al, 2017 ). The memristive devices fabricated using the sol–gel method have various areas of application and operate at a threshold voltage ranging from ~0.5 V (Abunahla et al, 2018 ) to 1.5 V (Vilmi et al, 2016 ; Hu et al, 2020 ) or higher (Illarionov et al, 2019 ) with a resistive switching ratio R OFF / R ON of 10 1 -10 5 ( Table 1 ).…”