Expanding Horizons of Metal Oxide-based Chemical and Electrochemical Sensors

Metal-oxide (MOx) are widely used in electrical/electrochemical sensors owing to their quick-response ability, High surface-to-volume ratio, matching lateral-dimensions with surface-charge zone and modifiable with dopants significantly enhances their sensing performance. Typically, MOx-based sensors are used in gaseous-analytes for monitoring environmental-pollutants and gas-leakage. Tuning the properties of nanostructured-metal-oxides advanced their applications beyond environmental-monitoring. This review focuses on the emerging-dimensions of MOx-based sensors in hazard-surveillance and risk-investigation like in deployment to detect fire-hazards, chemical-warfare agents, oil-spills and explosives. Recent advances of using MOx-based sensors as electronic-tongue and electronic-nose for non-invasive health monitoring and MOx-based sensor mobile robots for remote surveillance is also discussed.