Perovskite-based electrochemical sensing of ion and gas molecules: An overview

Perovskite materials, the most versatile class of materials among the entire crystal family, have been broadly employed for the sustainable development of society over the last few decades. They have gained much attention due to the unique characteristics of this crystal system, such as ease of structural modulation with tunable properties and flexibility in doping of new elements in the parent system. The diverse features make the perovskite materials extensively used in the fields of green energy harvest, photocatalysts, optoelectronics, sensors, and transducer applications. This chapter provides a brief overview of the newly developed perovskite oxide-based electrochemical sensors, present status, limitations, and future perspectives for research and development. Currently, a handful of perovskite-based sensing devices are capable of detecting metals or heavy metals, different anions, gas molecules, and other contaminants in the environment. Robust features like defects with a high tolerance, the confined and movable defects inside the structure that modify valance and conduction band properties, can result in a strong quantum turn out. Also, the overlapped band structure of perovskite nanomaterials effectively lowers the bandgap energy, which supports sensing applications. Perovskite property variation on A site and B site metal ion incorporation, sensing mechanisms, and parameters affecting sensing are the major focus of this chapter. Further, we have mentioned sensors recently developed by many research groups based on their changes in optical, electrical, and real-time monitoring of analytes. To conclude this chapter, pros and cons of perovskite oxide-based sensors and future prospects are discussed.