▎ 摘　　要

NOVELTY - Gas sensor comprises a hybrid material comprising metal halide perovskite nanocrystals and graphene deposited on a substrate with electrodes where the perovskite nanocrystals are embedded in graphene. USE - Gas sensor used for gas detection (claimed). ADVANTAGE - The gas sensor achieves highly reproducible, reversible, sensitive and ultra-fast detection at room temperature. The low noise levels in the response demonstrate that detection at trace levels (ppb) is possible. The perovskite nanocrystals are embedded in graphene and improves the sensitivity and performance of the sensor. Sensor life is improved. DETAILED DESCRIPTION - Gas sensor comprises a hybrid material comprising metal halide perovskite nanocrystals, of formula ABX3 and graphene deposited on a substrate with electrodes where the perovskite nanocrystals are embedded in graphene. INDEPENDENT CLAIMS are included for: (1) method for obtaining a sensor which involves (a) preparing a graphene dispersion; (b) exfoliating the graphene from the previous dispersion; (c) adding and mixing the perovskite nanocrystals to the exfoliated graphene solution to obtain a hybrid material of graphene and perovskite; (d) depositing the hybrid graphene and perovskite material on a substrate containing electrodes; and (2) gas detection method which involves (a) placing the sensors in a chamber through which the gas flow passes, and (b) measuring the variation in resistance after the passage of gas.