InSe-Based Sensors and Related Sensing Systems for NO₂ Gas/Temperature Monitoring

High-sensitivity, multiparameter sensing is increasingly critical for environmental monitoring and electronics. Existing sensing platforms struggle to integrate precise, rapid, and stable monitoring of parts per billion-level hazardous gases and temperature within a single miniaturized device. This study developed a novel sensor based on two-dimensional (2D) indium selenide (InSe), complemented by first-principles density functional theory calculations elucidating the layer-dependent NO₂ adsorption mechanism. The sensor demonstrated exceptional dual-mode performance, achieving a 103.40% response to 2 ppm of NO₂ alongside a broad temperature detection range (25-150 °C) with high sensitivity. To enable practical applications, we further integrated the sensor into a portable intelligent monitoring system that features signal acquisition, processing, and alarm. This integrated bifunctional platform significantly advances miniaturized, multiparameter sensing technology, offering a powerful solution for next-generation environmental monitors and devices.