September 22, 2025
Smog-Eating Coatings: 5 Powerful Ways Delhi Could Breathe
Smog-Eating Photocatalytic Coatings
Delhi has long struggled with severe air pollution, particularly in winter due to stubble burning, vehicular emissions, industrial activity, and weather conditions that trap pollutants.
- To combat this, the Delhi government plans to study and potentially deploy a new technology involving titanium oxide-based photocatalytic coatings.
About the Technology:
Titanium Oxide-Based Photocatalytic Coatings:
- These are special coatings applied to roads and public surfaces.
- They use sunlight and ultraviolet light to trigger a chemical reaction that breaks down pollutants, including:
Nitrogen dioxide (NO₂)
Harmful hydrocarbons (HCs)
- Converts toxic gases into less harmful compounds, improving air quality in heavily populated or high-traffic areas.
Global Use:
- Successfully tested and used in some international cities.
- First time being studied for large-scale application in India, especially in Delhi.
Key Details of the Delhi Plan:
Step-by-Step Approach:
- Within 30 days → Selection of a scientific partner to evaluate the technology.
- Field trials → Conducted on real city road stretches.
- Final report within six months → Includes safety, sustainability, and cost-effectiveness assessment.
Deployment Strategy:
- If successful, a Cabinet proposal will be introduced for city-wide implementation.
Priority locations:
- Busy traffic corridors
- Markets
- Public spaces
Focus Areas for Evaluation:
- Safety – Ensure no harmful side effects.
- Sustainability – Long-term environmental impact.
- Cost-effectiveness – Feasibility of mass rollout.
- Supplier Mapping – Identify credible manufacturers.
Expected Benefits
- Reduction of key pollutants like NO₂ and hydrocarbons.
- Improved air quality in high-density urban areas.
- People-first gains, especially for:
- Children
- Elderly
- Daily wage workers
- Vulnerable communities
Challenges & Considerations:
- High cost of titanium oxide and application process.
- Durability of the coating under Indian weather conditions.
- Maintenance requirements over time.
- Need for scientific validation through field trials before large-scale adoption.
- Coordination with municipal bodies and road authorities.
Significance for Delhi & India:
- If successful, Delhi could become a model city for other polluted urban centers in India.
- Aligns with India’s National Clean Air Programme (NCAP) and global commitments like SDG 11 (Sustainable Cities and Communities).
Represents a scientific and innovative approach to pollution control, beyond just regulatory measures.