Tuning Fluorescence\nResonance Energy Transfer in Cadmium\nTelluride-Diketopyrrolopyrrole Hybrids via Bandgap Engineering

Fluorescence resonance energy transfer (FRET) has been\nproven to\nbe an efficient sensitization method to construct broad-spectrum responsive\norganic–inorganic hybrid systems for efficient conversion and\nutilization of solar energy. To investigate the effect of the inorganic\nmaterial bandgap on FRET dynamics and mechanism, we have constructed\na series of cadmium telluride (CdTe) quantum dot (QD)-diketopyrrolopyrrole\n(DPP) hybrids via QD bandgap engineering. Steady-state and transient\nspectroscopy revealed that a fast and efficient FRET process was proceeded\nin these systems. Via controlling the spectral overlap degree between\nthem by adjusting the CdTe QD size, the FRET dynamics and direction\ncould be controlled effectively. A large spectral overlap integral\nbetween the emission of the donor and the absorption of the acceptor\nis crucial for realizing efficient and rapid FRET. These insights\ngained from this study contribute to the advancement of QD–dye\nnanocomposite materials, facilitating their application in a wide\nrange of fields.