Magnetised titanium dioxide (TiO2) for water purification: preparation, characterisation and application

Abstract

The study of titanium dioxide (TiO 2 ) as a photocatalyst for water purification has attracted significant attention over the past four decades. However, the separation of photocatalyst from water suspension may be difficult, costly and jeopardize the use of this water treatment technology. Recently, the development and production of magnetised TiO 2 have been achieved to offer a solution for the photocatalyst separation problem. This paper discusses the preparation techniques, characterisation and the applications of magnetised TiO 2 . Many researchers have studied magnetised TiO 2 photocatalysts but the lack of articles discussing the water purification processes is still slowing any advance in this field. Here, the progress of the scientific research on preparation techniques to coat magnetic particles by materials such as organic polymers, silica, magnesia and alumina are reviewed to compare and discuss recent findings. The doping of photoactive TiO 2 photocatalyst into the magnetic coated particles is also emphasised. In addition, the characterisation of magnetised TiO 2 in terms of physicochemical properties and operating conditions produced by each technique are critically reviewed. Moreover, examples of applications of TiO 2 and magnetised TiO 2 photocatalyst in water purification are summarised. In general, the effectiveness of organic removal by magnetised TiO 2 is still lower compared to single phase TiO 2 . The future prospect of this field is deliberated to develop a novel, economic and efficient magnetised TiO 2 photocatalyst, which has high organic removal properties.

Dysprosium substituted nickel cobalt ferrite nanomaterials and their composites with reduced graphene oxide for photocatalysis

“…The conversion of bulk titanium dioxide into nanobelts makes it more efficient for the removal of dyes during water cleaning. Titanium dioxide was also coated converted into magnetic material for easy recovery and to facilitate its repetitive usage as a photocatalyst [6]. Titanium dioxide was also coupled with ferrites.…”

Magnetically Recoverable and Reusable Titanium Dioxide Nanocomposite for Water Disinfection

“…Akvarez et al prepared Fe 3 O 4 /TiO 2 and Fe 3 O 4 /SiO 2 /TiO 2 (referred to as MS-TiO 2 ) nanoparticles and reported that incorporating a silica layer between the Fe 3 O 4 core and photocatalyst shell not only reduced the negative effect of magnetite on the photocatalysis process of TiO 2 but also protected the magnetic core against oxidation, retaining magnetic properties of the nanocomposite and enriching its removal efficiency [28]. Recently, a few publications described the construction of recyclable photocatalytic nanocomposites of Fe 3 O 4 /SiO 2 /TiO 2 with core-shell structure using sol-gel methods [29][30][31][32][33][34]. These studies focused on the nanocomposite's ability to photodegrade various organic pollutants.…”

Tailoring the stability/aggregation of one-dimensional TiO2(B)/titanate nanowires using surfactants

“…Among the extensive variety of metal oxide nanomaterials, titanium dioxide nanomaterials (TNMs) (e.g., anatase, rutile, TiO 2 (B) and titanate) have attracted considerable attention because of their unique physicochemical properties compared to the bulk material. TNMs play an important role in various applications such as photocatalytic degradation of organic pollutants [1–2], sensors [3–4], solid oxide fuel cells [5], water purification [6–7], adsorption of radioactive and heavy metal ions [8], as well as antibacterial applications [9]. Their various applications can be divided into “energy” and “environment” related categories.…”