Black titania; novel researches in synthesis and applications

Today, white Titania (W-TiO2) is very important photocatalyst because of its outstanding applications like production of H-2 using the sunlight and also to remove organic contaminants from the environment. Titanium dioxide is cost-effective in usage with useful chemical and biological properties and high oxidizing power. But, the significant drawbacks of using Titania for photocatalysis applications is in the transition energy gap between valence and conduction bands. Only UV photons can displace TiO2 valence layer electrons because of their high energy range and only use about 5% of solar radiation. To address this problem, the synthesis of hydrogenated titanium dioxide or black titania (B-TiO2) has been reported in 2011. Hydrogenation of titania can change several properties such as chemical, electronic, structural and optical absorption domain of nano-TiO2 extended to the IR region. These improved properties have led to new researches about the nano-black TiO2. There are many practical methods to produce black TiO2 and nowadays numerous applications have been reported for black TiO2 nanomaterials in various fields for example, in the field of medical applications for cancer treatment. The present study summarizes the novel and attractive ways to synthesize and new practical applications of black TiO2.