Chem Soc Rev
February 2023
Correction for 'Atomically flat semiconductor nanoplatelets for light-emitting applications' by Bing Bai , , 2023, , 318-360, https://doi.org/10.1039/D2CS00130F.
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January 2023
The last decade has witnessed extensive breakthroughs and significant progress in atomically flat two-dimensional (2D) semiconductor nanoplatelets (NPLs) in terms of synthesis, growth mechanisms, optical and electronic properties and practical applications. Such NPLs have electronic structures similar to those of quantum wells in which excitons are predominantly confined along the vertical direction, while electrons are free to move in the lateral directions, resulting in unique optical properties, such as extremely narrow emission line width, short photoluminescence (PL) lifetime, high gain coefficient, and giant oscillator strength transition (GOST). These unique optical properties make NPLs favorable for high color purity light-emitting applications, in particular in light-emitting diodes (LEDs), backlights for liquid crystal displays (LCDs) and lasers.
View Article and Find Full Text PDFSignificant advancements in perovskite light-emitting diodes (PeLEDs) based on ITO glass substrates have been realized in recent years, yet the overall performance of flexible devices still lags far behind, mainly being ascribed to the high surface roughness and poor optoelectronic properties of flexible electrodes. Here, we report efficient and robust flexible PeLEDs based on a mixed-dimensional (0D-1D-2D-3D) composite electrode consisting of 0D Ag nanoparticles (AgNPs)/1D Ag nanowires (AgNWs)/2D MXene/3D poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). Our designed MXene-based electrodes combine the advantages of facile formation of a film of low-dimensional materials and excellent optical and electrical properties of metal, inorganic, and organic semiconductors, which endow the electrodes with high electrical/thermal conductivity, flexibility, a smooth surface, and good transmittance.
View Article and Find Full Text PDFAlthough excellent performance such as high efficiency and stability have been achieved in quantum dot (QD)-based light-emitting diodes (QLEDs) possessing an organic/inorganic hybrid device structure, the highly expected all-inorganic QLEDs remain at the bottleneck stage in recent years, resulting from the luminance quenching of QDs caused by inorganic hole transport layer (HTL) and unbalanced charge injection due to large energy barrier for injecting holes from HTL to QDs. Here, it is reported that the solution-processed inorganic environmentally friendly chloride (Cl)-passivated tungsten phosphate (Cl@TPA) films serve as HTL. The incorporation of Cl in TPA effectively passivates the oxygen vacancies, which not only avoids the luminescence quenching of QDs by reducing carrier concentration but also facilitates the hole injection from HTL to QDs with a favorable electronic band alignment, thus achieving the record external quantum efficiency of ≈9.
View Article and Find Full Text PDFColor-saturated red light-emitting diodes (LEDs) with emission wavelengths at around 620-640 nm are an essential part of high-definition displays. Metal halide perovskites with very narrow emission linewidth are promising emitters, and rapid progress has been made in perovskite-based LEDs (PeLEDs); however, the efficiency of the current color-pure red PeLEDs-still far lags behind those of other-colored ones. Here, a simple but efficient strategy is reported to gradually down-shift the Fermi level of perovskite nanocrystals (NCs) by controlling the interaction between NCs and their surface molecular electron acceptor-benzyl iodide with aromatic rings-and realize p-doping in the color-saturated 625 nm emitting NCs, which significantly reduces the hole injection barrier in devices.
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