MOTIVATION AND GOAL
As modern people spend most of their time in indoor environments, the indoor air quality has emerged as one of the crucial concerns. The leading technology in market for removing indoor air pollutants is the adsorption technology using filtration media. However, there are various types of indoor air pollutants that has to be addressed using different types of technology. Our lab focuses on evaluating major pollution in indoor living environments and developing convergence technologies for treating air pollutants. Our future goal is to propose a new paradigm of “FIT-FOR-PURPOSE AIR PURIFICATION”.
ENVIRONMENTAL TECHNOLOGY (ET)
Advanced Oxidation Processes (AOPs)
AOPs are defined as processes which involve insitu generation of reactive oxygen species (ROS) to degrade environmental organic pollutants. Our aim is to develop various top-notch AOPs for treating environmental problems, especially for indoor air quality.
Photocatalysis is initiated by absorbing light with energy higher than the bandgap of semiconductors, thereby generate electrons and holes. Electrons react mainly with dioxygen to produce superoxide radicals and holes can be used for oxidizing water into hydroxyl radicals. The generated ROS react with adsorbed gas pollutants and mineralize them.
Photocatalytic air purification is an attractive technology since it can decompose gaseous pollutants directly into harmless CO2 and H2O under ambient conditions. It is particularly suitable to indoor environments where pollutants are present in sub-ppmv concentrations for which conventional adsorption filter technologies are not very efficient.
Single Atom Catalysts (SACs)
SACs represent a catalytic material which is engineered to exist as a ‘single atom,’ which is the theoretical limit in our endeavor to reduce the size of materials, resulting in improves catalytic performances. Since each atom in SACs is able to participate in catalytic reactions instead buried and inevitability wasted inside nanoparticles, the atomic efficiency reaches the theoretical maximum of 100%.
SACs can likewise be applied to environmental fields, opening a largely untapped opportunity and effortlessly incorporating catalysis into solving various challenging environmental problems.
GAS POLLUTION AND MATERIAL ANALYSIS TECHNIQUES
Taken in to account that gas density is much lower than aqueous molecules, it is difficult to measure the concentrations of gas pollutants accurately. Numerous monitoring techniques, including GC-MS, NDIR etc., as well as understanding on vacuum systems are required to evaluate efficiencies of developed technologies.
In addition, an understanding of the insitu-DRIFTs system that can reveal the degradation mechanisms of gas molecules is needed to predict the effective designs of environmental technologies
On top of the indoor air cleaner applications, our group is currently developing purification technologies for applying to operating rooms (surgery), gas masks, and mouth to treat bad breath.