Super accelerator of photocatalytic disinfection protects our respiratory health

As global public health awareness continues to increase, the health risks brought about by bioaerosol transmission have become a hot topic of concern in the scientific research community. Traditional bioaerosol disinfection technology faces multiple challenges such as low efficiency, limited disinfection effect on specific microorganisms, susceptibility to environmental conditions, and safety hazards. Against the backdrop of the public's increasing demands for health, hygiene, and environmental protection, the development of efficient and environmentally friendly disinfection technology has become a top priority.

Photocatalytic technology, as a cutting-edge oxidation treatment technology, has shown rapid development momentum in many fields in recent years. However, in the field of bioaerosol disinfection, this technology still has room for further improvement. Against this background, a study conducted in collaboration between Professor Wang Can of the School of Environment at Tianjin University and Professor Shen Zhurui of the School of Environment at Nankai University has achieved important results, bringing new opportunities for efficient and environmentally friendly bioaerosol disinfection technology . - The study prepared a single-layer Ti3C2Tx by etching and peeling off Ti3AlC2, and synthesized TiO2/single-layer Ti3C2Tx (T/mT) by a one-step solvothermal method. The rich functional groups on the surface of Ti3C2Tx enhance the hydrophilicity and surface free energy of the material. The Schottky heterojunction formed with the traditional semiconductor TiO2 generates a built-in electric field, prolongs the lifetime of photogenerated electrons, and significantly improves the photocatalytic reaction activity.

The disinfection effect of T/mT is significantly better than that of TiO₂. At the same time, the monolayer Ti3C2Tx promotes the combination of photocatalysts and biological structures. T/mT binds tightly to E. coli cells, changes the particle size distribution, and has a high affinity for proteins in the main components of the cell membrane. Molecular docking calculations show that the 2MHL outer membrane protein of E. coli cells is more likely to bind to T/mT. The binding process involves multiple interactions, which promotes the adsorption of materials on the cell membrane and facilitates the destruction of biological structures by reactive oxygen species (ROS) generated by photocatalysis.

The TiO2/single-layer Ti3C2Tx two-phase produces a space charge layer under the action of the electric field, which promotes the effective separation and transfer of photogenerated electrons and holes, and the generated ·O2⁻ and ·OH promote the disinfection process. In addition, photocatalysis damages the biological structure of Escherichia coli, such as the destruction of key structural chemical bonds such as proteins, phospholipids, and polysaccharides, the gradual mineralization of the microbial structure, and the change of the binding energy of related chemical bonds, which proves the extensive destructive effect of ROS on cell structure.

This research result not only points out the direction for the molecular structure design of photocatalytic air disinfection technology, but also lays the foundation for in-depth exploration of photocatalytic disinfection interface reactions. It highlights the huge potential of advanced oxidation technology in the field of bioaerosol microbial treatment, and has far-reaching significance for promoting the advancement of air disinfection technology.

About the Author :

Professor Wang Can, male, is a professor and doctoral supervisor at Tianjin University and the director of the Department of Environmental Engineering at Tianjin University. He has been engaged in research on the utilization and control of environmental microorganisms for a long time.

Research team introduction :

The gas utilization and control team of Tianjin University, with environmental microorganisms as the core, develops efficient biological purification technology for environmental pollutants and biological control technology for harmful microorganisms. The research directions of team members include: biological purification technology for organic waste gas, detection and control of bioaerosols, water and air disinfection technology, the basis of catalytic reaction and its application in biological control, and wastewater recycling technology (membrane method/electrochemistry), mainly involving basic and applied research in environment, biology, chemistry, chemical engineering, materials, medicine and other aspects.

For details of the study, please see the original article:
Accelerating photocatalytic bioaerosol disinfection at catalyst-cell interface via monolayer Ti3C2Tx introduction. Science Bulletin. doi: 10.1016/j.scib.2025.01.023