Recent Advances in Black TiO2 Nanomaterials for Solar Energy Conversion

Abstract

Titanium dioxide (TiO2) nanomaterials have been widely used in photocatalytic energy conversion and environmental remediation due to their advantages of low cost, chemical stability, and relatively high photo-activity. However, applications of TiO2 have been restricted in the ultraviolet range because of the wide band gap. Broadening the light absorption of TiO2 nanomaterials is an efficient way to improve the photocatalytic activity. Thus, black TiO2 with extended light response range in the visible light and even near infrared light has been extensively exploited as efficient photocatalysts in the last decade. This review represents an attempt to conclude the recent developments in black TiO2 nanomaterials synthesized by modified treatment, which presented different structure, morphological features, reduced band gap, and enhanced solar energy harvesting efficiency. Special emphasis has been given to the newly developed synthetic methods, porous black TiO2, and the approaches for further improving the photocatalytic activity of black TiO2. Various black TiO2, doped black TiO2, metal-loaded black TiO2 and black TiO2 heterojunction photocatalysts, and their photocatalytic applications and mechanisms in the field of energy and environment are summarized in this review, to provide useful insights and new ideas in the related field.

Understanding the pulsed laser‐induced modification processes of TiO2 nanomaterials in aqueous solution

“…For example, modification of TiO 2 using laser pulses has been also successfully employed to prepare visible responsive photocatalyst such as black TiO 2 15,16,28,29 . In this laser‐induced processes, 532 nm (or 355 nm) nanosecond laser pulses are directed to the TiO 2 particles suspended in water to produce black TiO 2 .…”

“…For example, modification of TiO 2 using laser pulses has been also successfully employed to prepare visible responsive photocatalyst such as black TiO 2 . 15,16,28,29 In this laser-induced processes, 532 nm (or 355 nm) nanosecond laser pulses are directed to the TiO 2 particles suspended in water to produce black TiO 2 . Black TiO 2 has been known to originate from the modification of the valence band edges induced by the structural disorder in the surface or defects (e.g., Ti 3+ and oxygen vacancies) 30,31 and often shows superior photocatalytic activities under visible light with excellent visible responses in dye degradation 16 as well as in hydrogen production.…”

All-inorganic lead halide perovskites for photocatalysis: a review

“…Besides dyes, the abuse of broad-spectrum antibiotics (ciprofloxacin, 305–307 norfloxacin, 308–311 2-mercaptobenzothiazole, 312 and tetracycline hydrochloride 313–315 ) causes harm to ecosystems and poses a threat to human health. Using all-inorganic lead halide perovskites, antibiotics can be successfully removed from water sources.…”

Au nanoparticle sensitized blue TiO2 nanorod arrays for efficient Gatifloxacin photodegradation

“…The oxygen vacancies in these materials can adjust the band structure, lower the band gap, enhance carrier separation and facilitate charge transfer, leading to enhanced catalytic activity. 17–19…”