Mechanochemical Forces as a Synthetic Tool for Zero- and One-Dimensional Titanium Oxide-Based Nano-photocatalysts

Abstract

A new field where the utilization of mechanochemistry can create new opportunities is materials chemistry, and, more interestingly, the synthesis of novel nanomaterials. Ball-milling procedures and ultrasonic techniques can be regarded as the most important mechanochemical synthetic tools, since they can act as attractive alternatives to the conventional methods. It is also feasible for the utilization of mechanochemical forces to act synergistically with the conventional synthesis (as a pre-treatment step, or simultaneously during the synthesis) in order to improve the synthetic process and/or the material’s desired features. The usage of ultrasound irradiation or ball-milling treatment is found to play a crucial role in controlling and enhancing the structural, morphological, optical, and surface chemistry features that are important for heterogeneous photocatalytic practices. The focus of this article is to collect all the available examples in which the utilization of sonochemistry or ball milling had unique effects as a synthesis tool towards zero- or one-dimensional nanostructures of a semiconductor which is assumed as a benchmark in photocatalysis, titanium dioxide.Graphical Abstract

When sonochemistry meets heterogeneous photocatalysis: designing a sonophotoreactor towards sustainable selective oxidation

“…3,[14][15][16][17] Highly photoactive materials are widely studied for application in environmental remediation in order to decompose/degrade hazardous compounds, but in most of the cases the outcome is complete and non-selective mineralization. 12,[17][18][19][20][21][22][23][24] The need for developing novel reactions for effective and selective valorization of organic compounds is in high demand, and two aspects can be assumed to be the most crucial: the development of a proper photoreactor and the use of a suitable photocatalyst for every specific photocatalytic reaction. Another strategy in order to elevate the photocatalytic reactions/transformations is to achieve process intensification by the application of alternative source of power.…”

Boosting the Photoactivity of Grafted Titania: Ultrasound‐Driven Synthesis of a Multi‐Phase Heterogeneous Nano‐Architected Photocatalyst

“…[12][13][14][15] The design and development of efficient and drawback-free TiO 2 -based catalysts is still an open and challenging issue, especially when selective photo-oxidation processes are targeted. [16,17] It has been shown that such features as porosity, morphology, surface chemistry heterogeneity, and size of particles have a decisive impact on the photoreactivity. [16] Mechanochemistry applied as a synthetic tool brings an advantage of altering and tuning these surface features on demand.…”

Recent advances on Bi2WO6-based photocatalysts for environmental and energy applications

“…Over the past few years, low dimensional (1D or 0D) nanomaterials have been widely used in the field of photocatalysis because of their unique optical and electronic properties [79][80][81][82][83]. 1D materials have the advantages of short diffusion path and easy strain relaxation, which are beneficial to the separation of photogenerated carriers.…”