Archive · 4 Oct 2026
Could Smog-Eating Paint Help Delhi-NCR Fight Air Pollution?
Smog-eating paint is a special coating, not ordinary paint that catches smog.
It often contains a material called titanium dioxide.
When sunlight shines on it, the material starts a chemical reaction.
That reaction can change some pollutants, including nitrogen oxides and certain gases, into other compounds.
Researchers want to find out how well this works on roads, pavements and other surfaces in Delhi-like conditions.
The results may depend on weather, dust and how much sunlight reaches the coating.
In March 2026, the Delhi government and IIT Madras agreed to study the idea.
The coating could be one extra way to help, but it cannot replace reducing pollution from vehicles, industry and construction.
Photocatalytic coatings, usually containing titanium dioxide, use sunlight to trigger reactions that can break down some pollutants.
Researchers are studying whether coated roads, pavements and other surfaces could reduce nitrogen dioxide and volatile organic compounds.
In March 2026, the Delhi government signed an MoU with IIT Madras to study these surfaces in local conditions.
Outdoor performance can vary with sunlight, humidity, temperature, wind, dust and how long pollutants contact the surface.
The coatings are being explored as an additional measure, not a replacement for cutting pollution at its sources.
- Who
- The Delhi government and IIT Madras are studying photocatalytic surfaces.
- What
- A study will examine whether titanium dioxide-based coatings can help reduce certain pollutants.
- When
- The Delhi government signed an MoU with IIT Madras in March 2026.
- Where
- Delhi and Delhi-NCR, under conditions relevant to the region.
- Why
- To assess whether sunlight-activated coatings on surfaces could help reduce pollutants such as nitrogen dioxide and volatile organic compounds.
Potential benefits
Limitations and cautions
Using city surfaces to reduce pollutants
Potential benefits
Coated roads, pavements and other surfaces could use sunlight to help break down some pollutants in the air.
Limitations and cautions
The effect outdoors varies with sunlight, humidity, temperature, wind, dust and the time pollutants remain in contact with the surface.
How much the technology can contribute
Potential benefits
The coatings could make existing urban surfaces an additional tool for cleaner air.
Limitations and cautions
They are not a replacement for reducing emissions from vehicles, industry, construction and other sources.
- Technology
- Photocatalytic coatings, typically containing titanium dioxide (TiO₂)
- How it works
- Sunlight triggers a reaction on the coating that can oxidise and transform some pollutants.
- Pollutants under study
- Nitrogen dioxide (NO₂) and volatile organic compounds (VOCs)
- Study partners
- Delhi government and IIT Madras
- Agreement date
- March 2026
- Potential surfaces
- Roads, pavements and other surfaces
- Key limitation
- Outdoor results vary with environmental conditions and contact between polluted air and the coated surface.
- Role in pollution control
- A possible additional measure, not a substitute for reducing emissions at their sources.