Organic-inorganic hybrid materials have the potential of providing excellent properties and promising novel optical properties. This work focuses on the white light emission process of one-dimensional (1D) organic-inorganic perovskite (C12H18N)PbBr3 abbreviated as 4BPP[PbBr3]. Contrary to most organic-inorganic hybrid material, where the organic moieties act as barriers and the inorganic part play the role of quantum well, both organic and inorganic parts in 4BPP[PbBr3] are optically active, giving rise to a strong and large emission band covering a wide range of the visible spectrum that can be seen even with the naked eye at room temperature. The photoluminescence spectrum is composed of three bands located at 490 nm (P1), 550 nm (P2) and 600 nm (P3). The first and the second bands are attributed respectivelyto and intra-molecular charge transfer transition within the 4BPP organic cation whereas the third band is related to the inorganic Wannier exciton confined in lead bromide PbBr3 chains. This result was supported by density functional theory calculation. Moreover, the temperature dependence of the PL emission for each transition reveals a different behaviour. In fact, a negative thermal quenching (NTQ) is observed for P1 evolution at low temperature. This NTQ emission is interpreted in terms of transitions between excitonic states involving an exciton-phonon interaction. The P2 observed emission behavior is explained by a charge carrier transfer mechanism between two quantum dots population and the P3 temperature quenching was explained by an increased level of non radiative recombination caused by the phonon vibration (80 cm−1) which corresponds well to Pb-Br stretching vibration observed in Raman spectra.
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