Emerging nano-enabled gas sensor for environmental monitoring – perspectives and open challenges

Proper vigilance on the levels of various gases of concern, especially the toxic ones, is vital for reducing the risk of environmental damage. This impels the demand for highly accurate and adequate gas-sensing systems, which are in demand but not in practice. This gap can be filled by fifth-generation nano-enabled gas sensors, which can offer room-temperature sensing, flexibility, high-selectivity, low-cost, self-powered operation, humidity resistance, and portable size. These features are the key requirements for integrating gas sensors into modern Internet-of-things systems. This perspective highlights trends and progressions (2020–2023) in developing tailored nanomaterials to fabricate cutting-edge gas sensors for high performance in the desired manner and conditions, for example, point-of-care, and point-of-location testing. The challenges associated with such materials and the scientific endeavors to address such issues have also been discussed.