Perovskite based photosensor for electrochemical studies

摘要

Photosensors are used for the detection of analytes in microfluidic devices. In order to detect materials with low concentrations, a sensor with high sensitivity is required. Perovskite has been studied extensively as a photoactive material in solar cells due to its wide absorption spectrum and low recombination rate of charges which also make it a suitable candidate for photosensors. In this work, the photoconductivity of the material in a thin-film resistor is studied. The resistance of the device is measured at different wavelengths and intensities. A significant change of the resistance is observed upon illumination indicating the adequacy of the device to serve as a photosensor. However, in this case, the perovskite layer must be protected with an insulating thin film to avoid undesired reactions and contacts. The perovskite film was also tested as an electrochemical photosensor. The current-voltage characteristics of the device showed a diode rectifying response both in dark and under illumination. In this case, the photo response of the device established promising results for applications in photosensors with a relatively high stability in a liquid media.