The self-cleaning fabrics work using the photocatalytic properties of titanium dioxide, compound used in many new nanotechnology solar cell applications. The fabric is coated with a thin layer of titanium dioxide particles that measure only 20 nanometers in diameter. When this semi-conductive layer is exposed to light, photons with energy equal to or greater than the band gap of the titanium dioxide excite electrons up to the conduction band. The excited electrons within the crystal structure react with oxygen atoms in the air, creating free-radical oxygen. These oxygen atoms are powerful oxidizing agents, which can break down most carbon-based compounds through oxidation-reduction reactions. In these reactions, the organic compounds (i.e. dirt, pollutants, and micro organisms) are broken down into substances such as carbon dioxide and water. Since the titanium dioxide only acts as a catalyst to the reactions, it is never used up. This allows the coating to continue breaking down stains over and over.

Working of self cleaning textiles

2. Using microwaves

New technology attaches nanoparticles to clothing fibers using microwaves. Then, chemicals that can repel water, oil and bacteria are directly bound to the nanoparticles.These two elements combine to create a protective coating on the fibers of the material. This coating both kills bacteria, and forces liquids to bead and run off. The same technology, created by scientists working for the U.S. Air Force, has already been used to create t-shirts and underwear that can be worn hygienically for weeks without washing.