Extensive CsAg ₂ I ₃ Microwire Array for Rapid-Response and Durable Humidity-Triggered Noncontact Sensors

Respiratory monitoring and fruit wax detection offer significant potential for personal health assessment, disease diagnosis, and the prevention of lethal virus transmission. Perovskites, recognized for facilitating the surface dissociation of water molecules, are widely employed in humidity-responsive electronics. However, inherent crystal defects critically compromise perovskite structural stability and charge transfer efficiency, degrading the device performance. To overcome these limitations, we utilized template-confined growth technology to fabricate CsAg₂I₃ perovskite microwires, achieving enhanced crystallographic stability and superior charge transport. This strategy yielded a highly stable, ultra-moisture-resistant noncontact humidity sensor exhibiting a 6.62 s response time, 4.26 s recovery time, and 5% RH detection limit. Remarkably, the sensor-maintained functionality for >60 days at 70% RH. It enables noncontact detection of finger perspiration and fruit surface moisture while achieving gesture recognition with ultrasensitive response kinetics. These capabilities establish a versatile platform for long-term respiratory monitoring, fruit wax detection, and human-computer interaction.