A highly-specific photoelectrochemical platform based on carbon nanodots and polymers functionalized...

Herein, we reported the introduction of carbon nanodots (CNDs) and polyvinylidene fluoride (PVDF) as additives into perovskite CH₃NH₃PbI₃ through in situ synthesis to prepare PVDF-CH₃NH₃PbI₃@CNDs composite, which demonstrated improved water tolerance and mechanical stability. The application of PVDF-CH₃NH₃PbI₃@CNDs for photoelectrochemical sensing was then explored. A molecularly imprinted polymer (MIP) that could specifically recognize cholesterol (CHO) was anchored to PVDF-CH₃NH₃PbI₃@CNDs via a simple thermal polymerization process, followed by elution with hexane. A label-free and sensitive photoelectrochemical method for CHO detection was achieved by using the MIPs@PVDF-CH₃NH₃PbI₃@CNDs platform. The detection limit for CHO was 2.1 × 10^-14 mol/L, lower than most of the existing CHO detection methods. In our perception, this platform can be extended to numerous other analytes. This research result may provide a new understanding to improve the performance and broaden the application range of organic-inorganic perovskites.