IoT-Based Environmental Monitoring and Nano-Photocatalytic Air Purification for Indoor Stadium Applications

Amid increasing concerns regarding airborne pollutant accumulation and pathogen transmission in densely occupied indoor sports arenas, this research investigates the integration of Internet of Things (IoT)-based environmental monitoring with nano-photocatalytic surface treatments for indoor air quality (IAQ) management in indoor stadiums. Zinc oxide (ZnO)-based nanophotocatalytic coatings were applied to interior walls, seating, and ventilation-adjacent surfaces within scaled stadium simulation models designed to replicate high-occupancy indoor conditions. Photocatalytic activation was achieved using controlled Ultraviolet Light Emitting Diode (UVLED) illumination to enhance degradation of airborne contaminants. An IoT-enabled sensing framework consisting of PM 2.5 , PM 10 , CO 2 , temperature, humidity, NO 2 , and volatile organic compound (VOC) sensors was deployed for continuous monitoring and wireless data transmission to a cloud-based analytics platform. Indoor air quality measurements were conducted during controlled 10-hour simulation cycles under varying occupancy and ventilation conditions. The experimental results confirmed that the integrated IoT and ZnO nano-photocatalytic framework achieved significant indoor pollutant reduction, including PM 2.5 (57.75–69.82%), PM 10 (62.66–75.31%), NO 2 (43.13–46.15%), VOCs (34.27–38.54%), microbial particles (33.50-43.95%), and AQI improvement up to 47.73%. Additionally, high IoT sensing accuracy (94.9–98.2%), stable cloud transmission (96.8–99.0%), and optimized airflow velocity conditions demonstrated effective environmental monitoring and sustainable indoor air quality management in indoor stadium environments. However, pollutant resuspension caused by crowd movement and fluctuating ventilation efficiency influenced treatment stability under peak occupancy scenarios. The findings confirm that combining IoT-based sensing technologies with nano-photocatalytic surface engineering provides a promising smart infrastructure solution for sustainable, energyefficient, and health-oriented air quality management in large indoor stadium environments.