en.Wedoany.com Reported - A novel core-shell structured titanium dioxide photocatalytic material, jointly developed by China Railway Shanghai Design Institute Group Co., Ltd. and Zhejiang Sci-Tech University, has been put into use on the "Star of the Yangtze River Delta," the first comfortable tourist train in the region. The train recently departed from Shanghai, carrying nearly 200 tourists on an 18-day journey to Xinjiang. According to Li Wei, Director of the Health Environment Research Institute at China Railway Shanghai Design Institute, the team applied a photocatalytic dispersion spray to the train just before departure to optimize cabin air quality, thereby building a health barrier for passengers, who are predominantly elderly.
Photocatalytic materials, represented by nano-titanium dioxide, have been recognized by the international scientific community since 1972 for their strong ability to degrade organic matter, decompose organic nutrients required by bacteria and viruses, and maintain stable physical and chemical properties while being harmless to humans. The industrialization of traditional photocatalytic materials has long faced two major bottlenecks: they only function under ultraviolet light, making them unsuitable for scenarios such as rail transit cabins and large office spaces; and they lack suitable organic carriers, limiting their daily application expansion.
The new photocatalytic material overcomes these challenges by constructing a "bird-in-cage" structure. Professor Wang Sheng from Zhejiang Sci-Tech University explains that titanium dioxide acts as the "bird," while a porous silica coating forms the "cage" around it. Gaseous pollutant molecules are drawn into the interior through small pores in the shell, where they come into contact with the photocatalytic material and are decomposed into carbon dioxide and water, which are then released through the pores, creating a purification cycle. This nanoscale core-shell structure not only resists photocorrosion and enhances material stability but also extends the photocatalytic application range from ultraviolet light to visible light.
This material can also be attached to organic flexible carriers such as textiles and films, avoiding the corrosion issues of traditional photocatalytic materials on carriers, thereby expanding its use to products like antibacterial clothing and filters for household appliances. On the bedding of the "Star of the Yangtze River Delta" train and the "Yangtze River Delta" silver-haired tourism special train to Xinjiang, the antibacterial rate remains stable at 99% after 50 washes. In tests on residential model rooms, indoor formaldehyde concentrations remain stably below national standard limits.
At the end of 2024, Zhejiang Sci-Tech University and China Railway Shanghai Design Institute jointly established a Space Purification New Materials R&D Center. The team completed the finalization and demonstration application of the core product, the "Photocatalytic Air Purification Device," within one year, and promoted the material to fields such as building decoration materials, health textiles, and functional lighting products. Li Wei stated that future efforts will focus on optimizing material performance, improving visible light utilization, reducing costs, expanding the product matrix, developing an "photocatalytic + intelligent" smart air treatment system, and promoting the establishment of industry standards.
