Design of a Plastic Inorganic Semiconductor GaPS4-Based Gas Sensor for Conformal Monitoring of Gas Lines

TL;DR

This paper introduces the first plastic inorganic semiconductor-based gas sensor using GaPS4, capable of conformal, high-sensitivity NO2 detection on curved surfaces, advancing flexible gas monitoring technology.

Contribution

It pioneers the application of plastic inorganic semiconductors in gas sensing, demonstrating a flexible, conformal sensor with high sensitivity and potential for performance improvements through defect engineering.

Findings

Achieved high sensitivity and selectivity for NO2 detection.

Demonstrated exceptional flexibility and conformability on curved surfaces.

Established a linear response range from 1 to 10 ppm at room temperature.

Abstract

This paper reports the first gas sensor based on the plastic inorganic semiconductor GaPS4, pioneering the application of plastic inorganic semiconductors in the field of gas sensing. Unlike traditional rigid sensors, this device leverages the unique layered structure and ultra-wide bandgap of GaPS4 to achieve high sensitivity and selectivity in detecting NO2. The intrinsic plastic deformability of the material enables it to conform tightly to complex curved pipelines like an "electronic bandage," completely eliminating monitoring blind spots. Nanoindentation tests reveal that its extremely low hardness (0.20 GPa) confers exceptional flexibility while maintaining stable electrical characteristics even under bent states. The device exhibits a linear response to NO2 concentrations ranging from 1 to 10 ppm at room temperature. Although the limited defects in the single-crystal material result in pA-level response currents, defect engineering offers a viable pathway for performance enhancement. This study breaks through the conventional boundaries of plastic inorganic semiconductors confined to photoelectric and thermoelectric applications, opening new avenues for their use in gas sensing and advancing gas monitoring technology toward "conformal integration."