A new lead halide perovskite-graphene hybrid applied to gas sensing has been developed. Ultra-fast sensors able to work at room temperature have been developed and the role in the gas sensing mechanisms of different ions in perovskite nanocrystals decorating graphene elucidated. Our invention shows for first time that the anion and cation in the perovskite structure (ABX3) have a significant effect on gas sensing performance. In particular, gas sensors employing graphene decorated with different perovskite configurations were successfully employed to detect voc vapours at ppm levels.
Description of the technology
The devices developed achieve highly reproducible, reversible, sensitive and ultrafast detection of vocs at room temperature. The low noise levels in sensor responses indicate that trace detection (at ppb levels) of VOCs would be possible. These results pave the way towards the development of reliable, inexpensive, durable and low-power chemiresistive sensors.
Monitoring aromatic VOCs is of interest due to their dangerousness (e.g. benzene is carcinogenic), and their detection at trace levels in the environment is very relevant for the petrochemical industry or air quality monitoring. Additionally, some VOCs constitute potential biomarkers for the detection of diseases at an early stage. For instance, the occurrence of some VOC concentration patterns in exhaled breath have been associated to sub-clinical lung cancer.
Current development status
The application can be the commercialisation of a new generation of low-cost gas sensors operating at room temperature (ultra-low power). Such sensors do not exist in the market. The use of different lead halide perovskites embedded in graphene flakes opens the possibility of fine tuning their gas sensing properties resulting in ameliorated selectivity. A small array of gas sensors with different perovskites can be used for detecting VOCs or other toxic species with enough sensitivity and specificity. The sensors offer great stability in humid air. The range of applications is wide from breath analysis (medical technologies), environmental monitoring (detection of NO2 and toxic VOCs), agro food industry (NH3 detection) and security (in petrochemical industry). Their stability and low cost make these gas sensor devices suitable for mobile gas detection in portable units, tags or wearables.
Desired business relationship