Subproject 3

SP3: Efficient Inactivation Technologies

SP3 will develop new filter designs and functional surfaces with efficient bioaerosol capture and inactivation properties. Several inactivation mechanisms will be investigated and optimized including catalytic action of TiO2-based nanomaterials, (bio)chemical functionalization, microwave heating and pulsed electromagnetic power, wet filtering, and direct airflow treatment. Together with the industrial partners, SP3 will offer a variety of products including: Membrane-based virus inactivating filters and sensors, photocatalytical inactivating surfaces, and air cleaning systems based on microwave-heating and wet filtering. 

Track-etched filters are ideal systems to investigate and optimize aerosol transport and interaction through porous systems. In addition, their surface can be functionalized in a controlled manner. The combination of surface functionalization and tailored pore geometry can be exploited to design filters with additional virus inactivation and virus detection capabilities.

Self-cleaning properties of photocatalytic materials like TiO2 can become invaluable tool to help combat the spread of the virus in high-traffic areas. Catalyst modification such as increasing reactive oxygen species (ROS) production or enhancing surface adsorption can be approached by self-doping of the catalyst and modification with metallic nanoparticles. In all these cases, the photocatalytic properties can be tailored by either modifying the band gap or inhibiting the recombination of charge carriers, subsequently leading to a greater amount of ROS at the surface and thus improves reaction kinetics.

Virus inactivation in filters based on microwaves, pulsed power and light aim to assess the fundamental applicability of microwave technology for air cleaning. A goal is an efficient in-situ virus inactivation that reduces hazards from active virus particles in filters and performs inactivation in a more efficient way.

Wet filtering and direct airflow treatment deals with options of filterless treatment of airborne pathogens. Wet filtering is known from non-medical aerosol removal tasks, e.g. in power plants. There, the airflow is guided through or along the surface of a liquid containing disinfectants. Furthermore, we investigate how air can be directly treated with infrared radiation. This concept is already used in KIT’s Aerobuster technology and will be further refined and assessed. Technologies will be transferred to Transfer Tandem Group.

Further developments into applicability of the technologies will be carried out in the work of the Transfer Tandem Group.