Related papers: Highly efficient light-emitting diodes based on in…
Organic light-emitting diodes (OLEDs) must be engineered to circumvent the efficiency limit imposed by the 3:1 ratio of triplet to singlet exciton formation following electron-hole capture. Here we show the spin nature of luminescent…
Organic light-emitting diodes (OLEDs) have redefined lighting with their environment-friendliness and flexibility. However, only 25 % of the electronic states of organic molecules can emit light upon electrical excitation, limiting the…
The development of luminescent organic radicals has resulted in materials with excellent optical properties for near-infrared (NIR) emission. Applications of light generation in this range span from bioimaging to surveillance. Whilst the…
In this study, we develop a steady state and time-dependent exciton diffusion model including singlet and triplet excitons coupled with a modified Poisson and drift-diffusion solver to explain the mechanism of hyper triplet-triplet fusion…
Organic light-emitting diodes (OLEDs) are central to modern display technologies and are promising candidates for low-cost energy-efficient lighting. Their performance is determined by numerous, intricate fabrication parameters, but not…
The efficiency of an organic light-emitting diode (OLED) depends on the microscopic orientation of transition dipole moments of the molecular emitters. The most effective materials used for light generation have threefold symmetry, which…
Spin triplet exciton formation sets limits on technologies using organic semiconductors that are confined to singlet-triplet photophysics. In contrast, excitations in the spin doublet manifold in organic radical semiconductors can show…
Utilization of triplet excitons, which generally emit poorly, is always fundamental to realize highly efficient organic light-emitting diodes (LEDs). While triplet harvest and energy transfer via electron exchange between triplet donor and…
Electroluminescence in organic light emitting diode (OLED) materials occurs via the recombination of excitonic electrons-hole pairs Only the singlet excitons of commonly used OLED materials, e.g., Aluminum trihydroxyquinoline (AlQ$_3$),…
Singlet-polaron and triplet-polaron annihilation mechanisms are the most detrimental exciton quenching processes that lower the efficiency of organic light-emitting diodes (OLEDs) at high current densities, causing so-called efficiency…
We develop a general theory of electron--hole recombination in organic light emitting diodes that leads to formation of emissive singlet excitons and nonemissive triplet excitons. We briefly review other existing theories and show how our…
The use of a thin mixed layer consisting of an inert diluent material and a light emitting material between the hole-transport layer and electron-transport layer of organic light-emitting diodes leads to an increase in the external quantum…
We have measured the ratio, r = $\sigma_S/\sigma_T$ of the formation cross section, $\sigma$ of singlet ($\sigma_S$) and triplet ($\sigma_T$) excitons from oppositely charged polarons in a large variety of $\pi$-conjugated oligomer and…
In this study, we fabricated hybrid white organic light-emitting diodes (WOLEDs) based on triplet harvesting with simple structure. All the hole transporting material and host in emitting layer (EML) of devices were utilized with same…
We fabricate OLEDs using a stable neutral {\pi} radical, BDPA, as the emitter. There is only one electron in the singly occupied molecular orbital (SOMO) of this open-shell molecule. This feature makes the excited state of open-shell…
We extend our theory of electron--hole recombination in organic light emitting diodes to investigate the possibility that high energy singlet and triplet excited states with large electron--hole separations are generated in such processes,…
Recent reports indicate that perovskite based light emitting diodes (LEDs) have achieved an external quantum efficiency (EQE) of 32% - rather an internal quantum efficiency close to 100%. Much of this improved performance is attributed to…
The quest for a spin-polarized organic light emitting diode (spin-OLED) is a common goal in the emerging fields of molecular electronics and spintronics. In this device two ferromagnetic electrodes are used to enhance the…
Controlling light-matter interactions is emerging as a powerful strategy to enhance the performance of organic light-emitting diodes (OLEDs). By embedding the emissive layer in planar microcavities or other modified optical environments,…
The power conversion efficiency of organic solar cells has recently improved beyond 20%. The active layers of these devices comprise of at least two organic semiconductors, forming a type II heterojunction. Hereby, the device performance is…