A Review on Nano TiO₂—A Repellent in Paint

Many technologies had origin through the continuous and careful observation of unnoticed features of the species present in our nature. The self cleaning property of lotus leaves is a remarkable one among them, known in the name “lotus effect”. It has found a huge place in the civil industry. The exterior house paints are always subjected to wide fluctuation in atmospheric temperature conditions such as exposure to winters, hot summers, raining, etc. which reduces its durability and causes algal growth. Thus by effective incorporation of nanotechnology with this lotus effect, it has become able to provide self-cleaning ability along with air purification and antibacterial performance to construction materials like paint, tiles, etc. Nanomaterials like silicon, Titanium Dioxide etc. help to improve functionalities like water or stain resistance, UV protection, scratch resistance etc. When nano TiO₂ was added to paint it degraded the polluting compounds at material surface by photocatalysis. Addition of it with cementitious materials displayed multiple photocatalytic functions and self cleaning properties. This review paper throws light into the repellent property of nano TiO₂ when used in paint thereby enhancing aesthetic appearance of surfaces and effectively reducing the cost of routine maintenance. Rhodamine B removal ability of nano TiO₂ is reviewed.