Photocatalytic
Air-Purifying Concrete Block
Dhaka ranks among the most polluted cities in the world, with toxic vehicle emission gases (NOx) posing grave health risks. AeroStone is an innovative, cost-effective construction block embedded with Anatase Titanium Dioxide (TiO₂) nanoparticles that degrades airborne nitrogen oxides into safe nitrates using sunlight.
Observed under simulated peak solar UV index inside a closed test reactor.
Requires no power grid, battery, or chemical consumables. Driven strictly by sunlight.
Nano-powder mix (5-7% dry weight cement) cures securely without washing off.
Nitrates are stored safely on the surface and wash away during precipitation.
Photocatalysis Chemistry
TiO₂ Photocatalysis Simulation
Interactive micro-level visualization of air purification on the concrete surface.
Photocatalytic Reaction Process
How to use this simulation:
Turn UV Active on or off, adjust the slider to see how solar radiation speed increases electron excitement, and click the steps to view chemical actions.
Environmental Impact Calculator
Ecological Impact Calculator
Adjust environmental variables to estimate nitrogen oxide (NOx) removal rates and AQI improvement.
Environmental Inputs
Tree Equivalent Filter
257 Mature Trees
Daily pollution filtering match.
Vehicle NOx Offset
9.6 Cars / Day
Offsets vehicle NOx emissions.
Purification Output
15,429 mg
NOx destroyed per day.
Degradation Efficiency
12.86 mg/m²/h
Calculated kinetic rate constant.
Air Quality Index (AQI) Impact
Estimated micro-climate local AQI drop.
24h Local AQI Curve Analysis
Note: Sunlight filter active from 8 AM to 4 PM (simulated peak UV at 12 PM).
Mix Design & Specs
Detailed chemical mix ratio of AeroStone block.
The concrete blocks utilize standard aggregate binding with a custom additive layer of Titanium Dioxide (TiO₂) in the anatase crystalline structure to guarantee photocatalytic activity.
| Material | Ratio % | Purpose |
|---|---|---|
| Portland Cement | 15.0% | Base hydraulic binder |
| Fine Aggregate (Sand) | 30.0% | Ensures micro-structural stability |
| Coarse Aggregate (Gravel) | 45.0% | Core structural block load support |
| TiO₂ (Anatase Nano) | 1.0% (Total Weight) | Catalyst agent (5-7% of Cement) |
| Water / Admixture | 9.0% | Hydration & flow enhancement |
Fabrication & Testing
Methodology and real-world science fair validation.
Mechanical Mixing: Aggregates, cement, and Anatase TiO₂ nanoparticles are thoroughly dry-mixed to prevent catalyst clumping before introducing water.
Vibratory Compaction: The mixture is placed in block molds and compressed using a vibratory compaction table to eliminate air voids and secure catalyst encapsulation.
Curing & Activation: The blocks undergo a 28-day water curing process. Post-curing, the block surface is lightly washed with weak acid to expose the TiO₂ nanoparticles.
Exhibition Laboratory Results:
We tested the AeroStone block inside a custom 50L acrylic chamber using a simulated gas input (800 ppb NO₂). Under a 150W UV bulb, the concentration dropped below 150 ppb (Good air quality limit) in just 35 minutes.