Black Titanium Dioxide Nanomaterials in Photocatalysis

Abstract

Titanium dioxide (TiO 2 ) nanomaterials are widely considered to be state-of-the-art photocatalysts for environmental protection and energy conversion. However, the low photocatalytic efficiency caused by large bandgap and rapid recombination of photoexcited electrons and holes is a challenging issue that needs to be settled for their practical applications. Structure engineering has been demonstrated to be a highly promising approach to engineer the optical and electronic properties of the existing materials or even endow them with unexpected properties. Surface structure engineering has witnessed the breakthrough in increasing the photocatalytic efficiency of TiO 2 nanomaterials by creating a defect-rich or amorphous surface layer with black color and extension of optical absorption to the whole visible spectrum, along with markedly enhanced photocatalytic activities. In this review, the recent progress in the development of black TiO 2 nanomaterials is reviewed to gain a better understanding of the structure-property relationship with the consideration of preparation methods and to project new insights into the future development of black TiO 2 nanomaterials in photocatalytic applications.

Photoelectrochemical properties of “increasingly dark” TiO2 nanotube arrays

“…It was suggested in Ref. [10] that surface oxygen vacancies and Ti 3+ states are responsible for the increased photocatalytic activity (via facilitating charge carrier separation), while in the bulk these defects act as trap states and charge carrier recombination centers. Thus, in our case it is possible that hydrogenation at moderate temperatures (below 500°C) induces the formation of defects mainly on the surface of the TNTAs, which leads to the enhanced IPCE.…”

“…Defective TiO2 nanomaterials can be synthesized by numerous methods, which have been well-reviewed in [10][11][12][13]. For instance, intrinsic defects can be introduced into crystallized TiO2 by applying reductive treatments (e.g.…”

Titanium Dioxide Photocatalysis

“…Strategies including doping; self-doping; and the realization of composites with plasmonic materials, 2D materials, other semiconductors, and quantum dots are of particular interest [1,2]. Black-TiO 2 visible light active photocatalysts [5], antimicrobial materials [6], photoelectrochemical devices for water splitting, and CO 2 photoreduction [7] are among the hot topics. The rational design elements of interests for efficient TiO 2 catalysts are optical properties, nanocrystal shape, and organization in superstructures.…”

Photo-Stabilisation and UV Blocking Efficacy of Coated Macro and Nano-Rutile Titanium Dioxide Particles in Paints and Coatings

“…Titanium dioxide exists in three crystalline modifications, rutile, brookite, and anatase, all of which have been prepared synthetically in various combinations and polymorphs [1][2][3][4][5][6][7][8][9][10]. It has the highest average refractive index known.…”