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Updated: Dec 15, 2025
Development of Efficient OLEDs from Solution Deposition
Published on: November 4, 2022
Tunable exciton binding energy in 2D hybrid layered perovskites through donor-acceptor interactions within the
James V Passarelli1, Catherine M Mauck2,3, Samuel W Winslow2
1Department of Chemistry, Northwestern University, Evanston, IL, USA.
Abstract:
The strength of electrostatic interactions within semiconductors strongly affects their performance in optoelectronic devices. An important target is the tuning of a material's exciton binding energy-the energy binding an electron-hole pair through the electrostatic Coulomb force-independent of its electronic band gap. Here, we report on the doping of a family of two-dimensional hybrid perovskites, in which inorganic lead halide sheets alternate with naphthalene-based organic layers, with tetrachloro-1,2-benzoquinone (TCBQ). For four out of seven n = 1 perovskites, the incorporation of the electron-accepting TCBQ dopant into the organic sublattice containing the electron-donating naphthalene species enabled the tuning of the materials' 1s exciton binding energy. The naphthalene-TCBQ electron donor-acceptor interactions increased the electrostatic screening of the exciton, in turn lowering its binding energy relative to the undoped perovskite-by almost 50% in one system. Structural and optical characterization showed that the inorganic lattice is not significantly perturbed even though the layer-to-layer spacing increases upon molecular dopant incorporation.
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