Reaching 90% Photoluminescence Quantum Yield in One-Dimensional Metal Halide C4N2H14PbBr4 by Pressure-Suppressed Nonradiative Loss
Citations Over TimeTop 10% of 2020 papers
Abstract
Low-dimensional perovskite-related metal halides have emerged as a new class of light-emitting materials with tunable broadband emission from self-trapped excitons (STEs). Although various types of low-dimensional structures have been developed, fundamental understating of the structure-property relationships for this class of materials is still very limited, and further improvement of their optical properties remains greatly important. Here, we report a significant pressure-induced photoluminescence (PL) enhancement in a one-dimensional hybrid metal halide C4N2H14PbBr4, and the underlying mechanisms are investigated using in situ experimental characterization and first-principles calculations. Under a gigapascal pressure scale, the PL quantum yields (PLQYs) were quantitatively determined to show a dramatic increase from the initial value of 20% at ambient conditions to over 90% at 2.8 GPa. With in situ characterization of photophysical properties and theoretical analysis, we found that the PLQY enhancement was mainly attributed to the greatly suppressed nonradiative decay. Pressure can effectively tune the energy level of self-trapped states and increase the exciton binding energy, which leads to a larger Stokes shift. The resulting highly localized excitons with stronger binding reduce the probability for carrier scattering, to result in the significantly suppressed nonradiative decay. Our findings clearly show that the characteristics of STEs in low-dimensional metal halides can be well-tuned by external pressure, and enhanced optical properties can be achieved.
Related Papers
- → Clarification of the relative magnitude of exciton binding energies in ZnO and SnO2(2022)19 cited
- → Interface-related effects on confined excitons in GaAs/AlxGa1−xAs single quantum wells(2002)9 cited
- → Exciton binding energy in V-shaped GaAs–Ga1−xAlxAs quantum wires(2001)4 cited
- → Exciton Binding Energies in Cd0.11Zn0.89S/Mg0.22Zn0.78S Quantum Wells Lattice-Matched to GaP Substrates(2009)
- → Modeling of Exciton Exchange Interaction in GaAs/AlGaAs Quantum Wells(2020)