Toward Robust and Discriminative Chemiresistive Gas Sensors: A Materials Perspective

Abstract Chemiresistive gas sensors are playing increasingly important roles in a wide range of applications, including environmental monitoring, clinical diagnostics, and industrial safety systems due to their inherent simplicity, scalability, and cost-effective signal transduction mechanisms. This perspective evaluates the evolution of sensing materials used in chemiresistors, spanning traditional semiconducting metal oxides to room temperature operating conducting polymers and carbon-based materials, as well as emerging metal−organic-frameworks. Despite significant advancements in their development, intrinsic selectivity and long-term operational stability remain significant challenges. Emerging strategies including hybrid composite materials, and artificial intelligence-driven design methodologies, alongside advances in fabrication techniques that govern microstructure, defect density, and interfacial properties, are discussed as promising avenues for developing robust, deployable sensing platforms. Finally, this perspective stresses the need for data sharing, rigorous validation protocols, and reproducible benchmarking procedures to ensure reliable performance comparisons and facilitate the transition from laboratory research to practical, real-world applications.