On August 25, 2024, Professor Fang Guohao research group published a research paper titled "Utilization of photocatalytic degradation and efficiency of engineered geopolymer composite tile doped with nano-particles under ultraviolet light" in the Journal of Cement and Concrete Composites(JCR Q1).The study examines the effects of nano-zinc oxide (ZnO) on the self-cleaning properties, life cycle assessment, and microstructural performance of engineered geopolymer composites (EGC) aimed at enhancing urban cleanliness.Eskinder Desta Shumuyeis the first author, Professor Fang is the corresponding author, the Institute for Advanced Study of Shenzhen University is the firstcompletion unit.

This research specifically investigates the uniform dispersion of nano-ZnO through ultrasonication to prevent agglomeration and examines its impact on the workability, setting time, mechanical properties, and microstructural characteristics of EGC. The results indicate that applying ZnO nanoparticles at concentrations of 5% and 10% as a surface coating on engineered geopolymer composites results in a highly efficient photocatalytic material. This improved composite exhibits a significant ability to degrade Rhodamine B (RhB) when exposed to UV light over 15-day period, effectively breaking down organic pollutants into simpler, potentially less toxic substances. The degradation efficiency is influenced by various factors, including the concentration of nano-ZnO, the intensity of UV radiation, and the initial concentration of the pollutant. The optimal nano-ZnO dosage in EGC is determined to be 0.5%, which enhances hydration and pozzolanic activity, leading to a more densified microstructure at the nanoscale. This innovative composite material holds promise as a self-cleaning finishing solution for urban buildings, potentially enhancing both aesthetics and environmental sustainability.

This research was supported by the National Natural Science Foundation andShenzhen Science and Technology Innovation Bureau. The original article can be found at:

https://www.sciencedirect.com/science/article/pii/S0958946524003020#ack0010

Fig.1 A new type of engineered geopolymer composite with properties of photocatalytic degradation