Current photocatalytic applications of nano-scaled titanium dioxide in the new era of “smart” technologies

Over the past decades, nanotechnology has increasingly developed and reached to monopolize almost all of the human activity areas. Materials with nanoscaled dimensions are not only developed for technological or medical purposes, but also, they can be found in daily commercial products. So, nanoparticles' applications found a welldefined place in our modern life. Almost 70% of global pigment production is based on titanium dioxide (TiO 2 ), which represents also one of the top five nanoparticles used in consumer products. TiO 2 surrounds our lives, being always present whether we want to take care of our health, wash our teeth or protect ourselves from harmful ultraviolet (UV) radiation. Moreover, TiO 2 is commonly used as a white pigment in different inks, paints, varnishes, plastics, papers, cosmetic products, also being the most common food additive (E171). But, the main perspectives of TiO 2 nanoparticles are related to different photo-induced phenomena, leading to the complete mineralization of pathogens and toxic non-biodegradable compounds, with low costs and high efficiency. Here, the authors aimed to present a brief review mainly focused on the ability of TiO 2 to create surfaces with self-cleaning, anti-fogging and antibacterial properties, as well as on the current photocatalytic applications of TiO 2 in new medical sanitizing techniques and biomedical devices development, wastewater management and air purification, energy and hydrogen production, and for obtaining "smart" clothes.