Reversible, Fast, and Wide‐Range Oxygen Sensor Based on Nanostructured Organometal Halide Perovskite

Abstract

Nanostructured materials characterized by high surface-volume ratio hold the promise to constitute the active materials for next-generation sensors. Solution-processed hybrid organohalide perovskites, which have been extensively used in the last few years for optoelectronic applications, are characterized by a self-assembled nanostructured morphology, which makes them an ideal candidate for gas sensing. Hitherto, detailed studies of the dependence of their electrical characteristics on the environmental atmosphere have not been performed, and even the effect of a ubiquitous gas such as O has been widely overlooked. Here, the electrical response of organohalide perovskites to oxygen is studied. Surprisingly, a colossal increase (3000-fold) in the resistance of perovskite-based lateral devices is found when measured in a full oxygen atmosphere, which is ascribed to a trap healing mechanism originating from an O -mediated iodine vacancies filling. A variation as small as 70 ppm in the oxygen concentration can be detected. The effect is fast (<400 ms) and fully reversible, making organohalide perovskites ideal active materials for oxygen sensing. The effect of oxygen on the electrical characteristics of organohalide perovskites must be taken into deep consideration for the design and optimization of any other perovskite-based (opto-) electronic device working in ambient conditions.

Porous Halide Perovskite–Polymer Nanocomposites for Explosive Detection with a High Sensitivity

“…Their extraordinary optoelectronic properties and solution processability can potentially lead to large area and high‐performance devices at a low cost. In parallel, using halide perovskites for detecting various gases and chemical species has been studied including oxygen, ozone, acetone, ethanol, ammonia, and explosive nitroaromatics …”

Superior Self‐Powered Room‐Temperature Chemical Sensing with Light‐Activated Inorganic Halides Perovskites

“…This still contribute to an increase in photocurrent by decreasing electron–hole recombination and allowing for more free charge carriers within CPB. Recently, it was observed that the MAPbI 3 perovskite demonstrates good gas sensing response to O 2 and it was proposed that the iodine anion vacancies in the perovskite play as the active sites for gas sensing process . Here, CPB demonstrates a similar gas sensing response to O 2 .…”

“…There is no orbital or electron contribution from the cation to the final electronic structure of lead halide perovskite, although the cation can still affect the electronic structure through the steric effect . Recently, it is pointed out that the surface trap sites in the perovskite play an important role in determining the optoelectronic properties . Meanwhile, it is also reported that a net positive charge formed at the perovskite surface due to the loss of bromide and undercoordination of the Pb atom at the surface, which causes the perovskite sensitive to the environmental gases.…”

Lasing Characteristics of CH3NH3PbCl3 Single‐Crystal Microcavities under Multiphoton Excitation

“…It is also observed that the reduction of temperature from room temperature to the cryogenic condition can change APbCl 3 from weak intensity emission to strong ASE respectively . Therefore, it is believed that the emission characteristics are in general sensitive to temperature and pressure . In this paper, we reveal the emission characteristics of APbCl 3 single crystals under the influence of temperature and pressure.…”