IIT Bombay’s new low-cost, thin coating material can reduce record heat

In a breakthrough in passive cooling, a team of engineers from IIT Bombay has developed a new low-cost, thin coating material that effectively reflects the sun’s heat, reducing heat absorption and providing thermal insulation. The material is hydrophobic, with fillers reducing heat conduction and imparting high infrared reflectance.

The researchers conducted tests where a coated surface was irradiated using an infrared lamp, decreasing the temperature by 15 to 21 degrees Celsius. This performance surpasses any previously reported coatings and boasts a high solar reflectance exceeding 72 per cent in the near-infrared region.

Prof. Smrutiranjan Parida from IIT Bombay stated, “Our work mainly prepared ‘active additives’ (called fillers), which can be added to a suitable resin to make a temperature shielding coating.” The coating includes two types of fillers – micron-sized silica-modified hollow microspheres and surface-modified Titanium dioxide nanoparticles.

Furthermore, the coating showed 99 per cent corrosion protection efficiency in tests involving exposure to Sodium Chloride solution, offering longevity and decreased maintenance costs for metal surfaces. The use of low-cost materials like hollow microspheres ensures an economically viable product in the market.

The team plans to enhance their coating material by adding fire-retardant properties and exploring the production of a VOC-free waterborne coating system for increased environmental friendliness. Their innovative approach may revolutionize the field of passive cooling technology and sustainable building materials.