Large photoluminescence enhancement in the chlorophyll from the energy transfer in perovskite–chlorophyll hybrid derivatives

Determining the photophysical processes for biomaterial–semiconductor systems has been beneficial for developing optoelectronic devices that exhibit biodegradability and biocompatibility. Here, we systematically investigated the optical properties and photophysical mechanisms of CsPbBr3 nanoparticles (NPs)-incorporated chlorophyll material. Steady-state photoluminescence (PL) studies reveal a large fluorescence enhancement in the chlorophyll once the perovskite was incorporated in the pristine chlorophyll with an associated PL quenching of the CsPbBr3 emission. A spectral overlap was measured from the PL and absorption spectra of CsPbBr3 NPs and chlorophyll indicative of a Förster-type resonance energy transfer (FRET). Using time-resolved PL, faster PL decay curves were observed from the CsPbBr3 NPs in the mixture suggesting that most of its energy was transferred to the chlorophyll. The corresponding Jablonski diagram was built and the energy transfer parameters, such as FRET efficiencies and transfer rates, were calculated to fully explain the FRET process. Slow PL degradation for the mixtures was also observed, highlighting the advantage of the FRET proposed. The demonstration of the photophysical mechanism in biomaterial–semiconductor systems is influential in improving the performance of emerging bio-inspired optoelectronic devices.