Oral Presentation Royal Australian Chemical Institute National Congress 2026

Controlling photoactivity in ZnO nanoparticles to improve safety and stability (136721)

Mina Mohebimorad 1 , Antonio (Tony) Patti 1 2 , Alison Funston 1 , John Warner 1 , Terry Turney 1 3
  1. Monash university, Clayton, VICTORIA, Australia
  2. ARC Industrial Transformation Training Centre, Green Chemistry in Manufacturing, Melbourne, victoria, Australia
  3. Micronisers Australasia , Melbourne, victoria, Australia

Ultraviolet (UV) radiation poses significant risks to both human health and the environment. Consequently, developing efficient UV-protective materials is of great importance to society. Zinc oxide (ZnO) is widely recognized as a highly effective UV filter and is commonly incorporated into sunscreens and personal care products, with toxicological studies indicating good biocompatibility even at the nanoscale. [1] ZnO functions as a physical shield by scattering and absorbing UVA and UVB radiation, thereby reducing skin damage and lowering the risk of UV-related carcinogenesis. [2]

Despite these advantages, the long-term industrial deployment of ZnO-based UV-blocking materials remain challenging due to its residual photocatalytic activity. With prolonged exposure, ZnO can degrade various organic contaminants, dyes, and certain inorganic compounds into less harmful species. [3] While this property is beneficial in applications such as water and air treatment, photodetectors, and solar energy devices, it presents a significant limitation for the use of ZnO in protecting organic materials, coatings, and polymer-based products from UV exposure. [4]

There is an urgent demand for improved formulations that deliver strong UV protection while limiting photo-oxidative degradation. This study focuses on tailoring the properties of ZnO nanoparticles to maintain their UV-shielding capability while reducing or eliminating photocatalytic activity, through the exploration of surface modifications, chemical additives, and a more detailed investigation of the underlying mechanisms. The objective is to enhance the longevity and performance of both personal care and industrial formulations, ultimately improving product reliability and consumer safety.

  1. [1]. Wright, P.F.A., Journal of Investigative Dermatology; 2019, 139, 277-278. [2]. Schneider, S. L., & Lim, H. W, Photodermatology, Photoimmunology & Photomedicine; 2018, 35(6), 442–446. [3]. Nagar, V., Singh, T., Tiwari, Y., Aseri, V., Pandit, P. P., Chopade, R. L., Pandey, K., Lodha, P., & Awasthi, G, Materials Today: Proceedings; 2022,69, 56–63. [4]. https://www.stratco.com.au/about/Blog/how-to-prevent-sunscreen-damaged-colorbond-steel/