Smart Humidity Sensor Based on Cs₃Cu₂I₅ Nanorods for Real-Time Monitoring of Leakage of Respiratory Protective Equipment

The presence of leakage in respiratory protective equipment undermines its intended efficacy in protection. Therefore, the real-time monitoring of leakage in respiratory protective equipment is of paramount importance. In this work, a lead-free humidity sensor based on Cs3Cu2I5 nanorods was utilized to achieve the leakage detection of respiratory protective equipment. Addition of the organometallic ligand Al(acac)(3) improved the stability of the material and contributes to long-lasting stable applications. Cyclic response testing demonstrated rapid response/recovery times of 2.98/2.96 s in the humidity range 20 similar to 80% RH. Further explanation of the moisture sensitivity mechanism and rationalization of RPE leakage monitoring through humidity were explored by density functional theory calculation and computational fluid dynamics calculation. Then, the sensor array was integrated into the respirator and combined with a deep learning algorithm to detect leakage. The results showed that respirator leakage can be effectively identified with an average accuracy of 94.4%, which contributes to the protection of workers' health.