Facile synthesis of brookite TiO₂ nanoparticles

Abstract

A simple method has been developed for synthesis of phase-pure and highly crystalline brookite TiO2 nanoparticles from a broad range of titanium precursors.

Polymorphic control in titanium dioxide particles

“…The experimental conditions and parameters employed to isolate brookite phase TiO 2 nanoparticles using the PIT-nano-emulsion synthesis described here were compared to other reported methods (Supporting Information) to provide evidence of the ability of the described parameters to crystallize and isolate phase-controlled TiO 2 brookite nanoparticles with high purity employing fewer toxic compounds, reducing the quantity of starting materials, and with the minimum energy input when compared to other previously employed methods. [24][25][26] Rutile and Anatase Phases. The H 2 O:HNO 3 /Heptane (rutile) or H 2 O:NaOH/Heptane (anatase) emulsion systems were prepared and homogenized.…”

“…The addition of polymorph-regulating agents such as glycolic acid and NH 4 OH was coupled to the PIT-nanoemulsion synthesis to promote the formation of a titanium glycolate complex, as reported by Mamakhel et al 24 As an advantage of introducing the PIT-nano-emulsion method is formation of the complex inside of the aqueous nanospheres to control its particle size. Once formed, thermal treatment at 200°C inside of an digestion bomb was conducted for 20 h. 24 Here, the final experimental steps in the designed PIT-nano-emulsion synthesis after thermal treatment could lead the formation of highly-pure brookite phase nanoparticles employing fewer toxic compounds, reducing the quantity of starting materials, and with minimum energy input when compared to previously employed methods (Supporting Information). [24][25][26] Raman spectroscopy.…”

“…Once formed, thermal treatment at 200°C inside of an digestion bomb was conducted for 20 h. 24 Here, the final experimental steps in the designed PIT-nano-emulsion synthesis after thermal treatment could lead the formation of highly-pure brookite phase nanoparticles employing fewer toxic compounds, reducing the quantity of starting materials, and with minimum energy input when compared to previously employed methods (Supporting Information). [24][25][26] Raman spectroscopy.…”

DFT study of TiO2 brookite (210) surface doped with silver and molybdenum

“…Most investigations of TiO 2 photocatalysis have focused on rutile and anatase polymorphs, with very few attempts at brookite due to the fact that it is difficult to synthesize in the laboratory [10]. However, in recent years effective methods for synthesizing high-purity brookite TiO 2 have been developed, which has sparked an increasing amount of interest in the physicochemical characteristics and potential uses of this TiO 2 polymorph [29]. Some comparison studies have previously been carried out, the results indicating that brookite may have higher activity than rutile and anatase in photocatalysis, as well as in catalytic processes involving TiO 2 supported metal clusters [30][31][32].…”

Near-IR photoluminescence and structural properties of TiO2 powders with nanocrystalline anatase/brookite matrix

“…Until recently, major research attention has been dedicated to the creation of photoactive materials to be based on anatase and rutile polymorphs of titanium dioxide and on their combinations [1][2][3]. It is only over the last years that intensive studies have been under way, reporting one more low-temperature, metastable polymorph of titanium dioxide, namely, brookite and its combinations with anatase [4][5][6][7][8][9][10][11]. Brookite has an advantage that is perceived to be in having structural defects/electron traps with the energy depth greater than that of anatase and smaller than that of rutile, which favors a more effective process of separation of photogenerated electron-hole pairs and provides for a longer life of charge carriers [10].…”