How does the use of photocatalytic concrete reduce urban heat island effects?

Urban heat island (UHI) effects, where cities experience significantly higher temperatures than surrounding rural areas, are a growing concern due to climate change and urbanization. Photocatalytic concrete offers an innovative solution by actively reducing surface heat and improving air quality.

This specialized concrete contains titanium dioxide (TiO2), which acts as a photocatalyst when exposed to sunlight. The process triggers two key reactions:

1. Heat Reduction: The material reflects more solar radiation than traditional concrete, lowering surface temperatures by up to 10°C.

2. Pollutant Breakdown: It decomposes nitrogen oxides (NOx) and other pollutants, reducing smog formation that contributes to heat retention.

Additional benefits include:

- Improved albedo effect through light-colored surfaces

- Self-cleaning properties that maintain reflectivity

- Compatibility with existing infrastructure projects

Cities like Tokyo and Los Angeles have successfully implemented photocatalytic concrete in pavements and building facades, demonstrating measurable decreases in local temperatures. As urban areas expand, this technology presents a scalable approach to mitigate heat islands while addressing air pollution challenges.