Andrey V. Kalinichev, Daniel E. Lucani, Klaus Koren
Chemical sensors have the potential to transform how we monitor the world. When connected through the Internet of Things (IoT), they could enable real-time tracking of a wide range of phenomena, from air pollution to personal health. While physical sensors for temperature and motion have scaled with ease, chemical sensors have not. They drift, degrade, require calibration, and often respond to multiple parameters. Their performance outside the lab remains inconsistent, and their integration into real-world IoT systems remains limited, despite decades of research. This Perspective review examines why progress has been so difficult. We explore key technical challenges, including the difficulty of managing chemical data on a large scale. What we have observed is that the obstacles are not only technical but also structural. Chemistry, engineering, and computing continue to evolve in isolation, with few shared standards and limited cross-disciplinary coordination. We argue that building reliable chemical sensor networks will require a shift in mindset. Sensors must be reliable. Data must be meaningful. Systems must work together. The only way forward is through coordination across fields and institutions. The Perspective is structured in three parts. First, we outline the main barriers holding back scalable chemical sensing. Next, we highlight practical opportunities for progress. Finally, we offer a forward-looking outlook on where the field is heading and what must change. Our vision, from the ground to the data cloud, is a future where chemical sensors become fully trusted, interoperable nodes in global digital ecosystems.