A5063218435- Organic Light-Emitting Diodes Research
- Organic Electronics and Photovoltaics
- Perovskite Materials and Applications
- Conducting polymers and applications
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Quantum Dots Synthesis And Properties
- Semiconductor materials and devices
- Luminescence and Fluorescent Materials
- Chalcogenide Semiconductor Thin Films
- Thin-Film Transistor Technologies
- Molecular Junctions and Nanostructures
- Semiconductor materials and interfaces
- Transition Metal Oxide Nanomaterials
- Electron and X-Ray Spectroscopy Techniques
- Silicon Nanostructures and Photoluminescence
- Electronic and Structural Properties of Oxides
- Porphyrin and Phthalocyanine Chemistry
- Crystallography and molecular interactions
- ZnO doping and properties
- Gas Sensing Nanomaterials and Sensors
- Semiconductor Quantum Structures and Devices
- Solid-state spectroscopy and crystallography
- Graphene research and applications
- Electrochemical Analysis and Applications
University of Toronto
2016-2025
Yunnan University
2016-2025
Soochow University
2022-2025
Tsinghua University
2017-2024
Jilin Normal University
2024
Wuhan University
2024
Bridge University
2024
Institute of High Energy Physics
2024
University of Chinese Academy of Sciences
2024
Guangxi University
2024
Planar perovskite solar cells (PSCs) made entirely via solution processing at low temperatures (<150°C) offer promise for simple manufacturing, compatibility with flexible substrates, and perovskite-based tandem devices. However, these PSCs require an electron-selective layer that performs well similar processing. We report a contact-passivation strategy using chlorine-capped TiO2 colloidal nanocrystal film mitigates interfacial recombination improves interface binding in low-temperature...
A two-step ligand-exchange strategy is developed, in which the long-carbon- chain ligands on all-inorganic perovskite (CsPbX3 , X = Br, Cl) quantum dots (QDs) are replaced with halide-ion-pair ligands. Green and blue light-emitting diodes made from halide-ion-pair-capped exhibit high external efficiencies compared untreated QDs.
Abstract Transition metal oxides are capable of a wide range work functions. This quality allows them to be used in many applications that involve charge transfer with adsorbed molecules, for example as heterogeneous catalysts, charge‐injection layers organic electronics, and electrodes fuel cells. Chemical structural factors can alter transition‐metal oxide functions, often making their functions difficult control. Little is known about the effects cation oxidation state point defects on...
Perovskite light-emitting diodes (PeLEDs) have shown excellent performance in the green and near-infrared spectral regions, with high color purity, efficiency, brightness. In order to shift emission wavelength blue, compositional engineering (anion mixing) quantum-confinement (reduced-dimensionality) been employed. Unfortunately, LED profiles increasing driving voltages due either phase separation or coexistence of multiple crystal domains. Here we report color-stable sky-blue PeLEDs...
Closer matching of the energy levels transparent electrodes and active materials in organic light-emitting diodes improves efficiency.
Strain-stabilized perovskites The perovskite materials used for solar cells and light-emitting diodes (which are black in color) generally less stable at room temperature than the electronically inactive nonperovskite phases yellow color). Steele et al. show that CsPbI 3 , strain induced a thin film after annealing material to 330°C then rapidly cooling it kinetically trapped phase. Grazing-incidence wide-angle x-ray scattering revealed crystal distortions texture formation created by...
Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, low photoluminescence quantum efficiencies, especially low-excitation regimes, limit efficiency light emission. Consequently, perovskite light-emitting devices operated under high injection, regime which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into small subpopulation...
Thin-film metal oxides are among the key materials used in organic semiconductor devices. As there no intrinsic charge carriers a typical semiconductor, all charges device must be injected from electrode/organic interfaces, whose energetic structure consequentially dictates performance of The energy barrier at interface depends critically on work function electrode. For this reason, various types thin-film can as buffer layer to modify electrode function. This paper provides review recent...
Abstract When transition metal oxides are used in practical applications, such as organic electronics or heterogeneous catalysis, they often must be contact with a metal. Metal contacts can affect an oxide's chemical and electronic properties within the first few nanometers of contact, resulting changes to reactivity, conductivity, energy‐level alignment properties. These effects alter ability perform its intended function. Thus, choice contacting becomes important design consideration when...
Over the span of past decade, carbon dots (CDs) synthesized from renewable organic resources (organic CDs) have gathered a considerable amount attention for their photoluminescent properties. This review will focus on CDs using clean chemistry and conventional synthetic sources fluorescence mechanisms, such as quantum confinement effect surface/edge defects, before outlining performance in electronic applications, including photovoltaic devices, light-emitting biosensors, supercapacitors,...
Abstract The all‐inorganic nature of CsPbI 3 perovskites allows to enhance stability in perovskite devices. Research efforts have led improved the black phase films; however, these strategies—including strain and doping—are based on organic‐ligand‐capped perovskites, which prevent from forming close‐packed quantum dot (QD) solids necessary achieve high charge thermal transport. We developed an inorganic ligand exchange that leads QD films with superior increased atomic‐ligand‐exchanged...
Blue-emitting perovskites can be easily attained by precisely tuning the halide ratio of mixed (Br/Cl) (MHPs). However, adjustable hinders passivation Cl vacancies, main source trap states leading to inferior performance blue MHP light-emitting diodes (LEDs). Here, we report a strategy for passivating vacancies in quantum dots (QDs) using nonpolar solvent-soluble organic pseudohalide [n-dodecylammonium thiocyanate (DAT)], enabling LEDs with greatly enhanced efficiency. Density functional...
The first examples of BMes(2)-functionalized NHC chelate ligands have been achieved. Their Pt(II) acetylacetonate complexes synthesized and fully characterized. These NHC-chelate compounds display highly efficient blue or blue-green phosphorescence in solution (Φ = 0.41-0.87) the solid state 0.86-0.90). Highly electroluminescent devices based on these new also fabricated.
The density of trap states within the bandgap methylammonium lead iodide single crystals is investigated. Defect close to both conduction and valence bands are probed. Additionally, a comprehensive electronic characterization carried out, including measurements electron hole mobility, energy landscape (band diagram) at surface.
Abstract Reduced-dimensional perovskites are attractive light-emitting materials due to their efficient luminescence, color purity, tunable bandgap, and structural diversity. A major limitation in perovskite diodes is limited operational stability. Here we demonstrate that rapid photodegradation arises from edge-initiated photooxidation, wherein oxidative attack powered by photogenerated electrically-injected carriers diffuse the nanoplatelet edges produce superoxide. We report an...