Effect of Donor-Acceptor Concentration Ratios on Non-Radiative Energy Transfer in Zero-Dimensional Cs₄PbBr₆ Perovskite/MEH-PPV Nanocomposite Thin Films

Composite materials with different concentration ratios of a hybrid of zero-dimensional (0-D) Cs₄PbBr₆ perovskite, which acts as a donor (D), and poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV), which acts as an acceptor (A), were successfully prepared via a solution blending method prior to being deposited onto glass substrates by a spin-coating technique. The influence of acceptor content on the structural, optical, and energy transfer properties of the donor was investigated. The perovskite nanocrystals formed thin films without any chemical interactions within a matrix of MEH-PPV in the blend. The possibility of dipole-dipole (non-radiative) energy transfer from the 0-D Cs₄PbBr₆ to the MEH-PPV was proven. The energy transfer parameters such as R_o (critical distance of the energy transfer), k_app (apparent quenching constant), ∅DA (quantum yield of D in the presence of A), τDA (lifetime of D in the presence of A), P_DA (probability of energy transfer), η (efficiency of energy transfer), R_DA (energy transfer radius), k_ET (energy transfer rate constant), T_DR (total decay rate), A_o (critical concentration of A), and A_π (conjugation length) were calculated based on the absorption and emission measurements.