ASSISTANT Professor Tan Swee Ching and his Ph.D. student Sai Kishore Ravi, from the Department of Materials Science & Engineering, have developed an innovative nanofibre solution that creates thin, see-through air filters that can remove up to 90 per cent of PM2.5 particles, and achieve high air flow of 2.5 times better than conventional air filters. This results in better breathability, and the particle filtration efficiency can be further enhanced, depending on the purpose and functionality of the air filter.
The NUS Engineering research team’s air filters are also eco-friendly and easy to produce – you simply apply the nanofibre solution onto ordinary non-woven mesh, and leave it to dry naturally. In addition, the eco-friendly air filters improve natural lighting and visibility, while blocking harmful ultraviolet (UV) rays.
Using phthalocyanine, a chemical compound commonly used in dyeing, the researchers modified organic molecules that could self-organise, similar to the stacking of building blocks, to form nanoparticles and subsequently, nanofibres. The nanofibres, which exist in the form of an organic solution, easily “cling” onto the non-woven mesh when dispersed onto the material.
The developed air filters, using the novel nanofibre solution, are two times better in quality than commercial ones, and are suitable for applications on windows and doors to improve indoor air quality. The novel air filters also have promising applications in respirators.
“Air pollution poses serious health threats. Therefore, there is a strong need for economical and effective technologies for air filtration. Currently, most nanofibres used in air filters are energy intensive to produce and require specialised equipment. Our team has developed a simple, quick and cost-effective way of producing high-quality air filters that effectively remove harmful particles and further improves indoor air quality by enhancing air ventilation and reducing harmful UV rays. In the long run, it may even be possible for a DIY (do-it-yourself) kit to be made available commercially for consumers to make air filters at home,” explained Asst Prof Tan, the lead researcher.
The research team has filed a patent for this novel invention, and is looking into adding more functionalities, such as anti-bacterial properties, into the air filters. The researchers also plan to work with industry partners to commercialise the novel technology.