Answer: Delhi
Notes: Delhi government and Indian Institute of Technology Madras are studying “smog-eating” photocatalytic road coatings to reduce air pollution. The coating neutralizes harmful gases like nitrogen dioxide and volatile hydrocarbons present in polluted air. It mainly uses Titanium dioxide which is low-cost, chemically stable and compatible with construction materials. Titanium dioxide-based materials help in gaseous depollution and environmental cleaning. Photocatalysis works by using light energy to break down harmful pollutants and organic waste into less toxic or harmless substances. This process helps improve air quality and contributes to cleaner environment.
