Further advancements in OLED-based display performance are required, particularly in terms of energy effectiveness and colour purity, both of which have a direct impact on power usage. A group of researchers have proposed a number of new chemical compounds to act as OLED emitters.
An organic semiconductor layer sandwiched between two electrodes, one of which is transparent to allow light to pass through, makes up the light-emitting portion of an OLED. A group of researchers have proposed a number of new chemical compounds to act as OLED emitters. Dr Marcin Lindner of the Institute of Organic Chemistry, Polish Academy of Sciences, founded their research consortium.
Dr Lindner created a number of promising novel emitters based on aromatic electron-donating and -accepting moieties connected by an antiaromatic seven-membered ring, which launched this study. A moiety is a component of a molecule that has a name in organic chemistry because it is recognised as a component of other molecules as well.
The choice of the electron-donating group, a nitrogen-doped (or, N-doped) PAH moiety, is another novel feature of Dr Lindner’s design. The molecular skeleton takes on a concave, bowl-like form as a result of the nitrogen doping, which helps to lessen unwanted stacking interactions in the condensed phase.
Prof. Przemysaw Data, a spectroscopist from the Silesian University of Technology, comprehensively evaluated the optical and electrical characteristics of N-doped PAHs. Notably, Prof. Data’s research team assessed the energy levels of the molecular orbitals and captured the emission spectra of the N-doped PAHs under various sets of settings.
Prof. Data’s group also created prototype OLEDs with the novel chemicals and assessed the external quantum efficiencies of these devices (EQEs). It was discovered that the best-performing N-doped PAH had an EQE of 12 percent, which was higher than the EQE of comparable current donor-acceptor emitters.
The team, under the direction of Dr Adam Kubas, a theoretical chemist from the Institute of Physical Chemistry, Polish Academy of Sciences, supplemented the experimental work with quantum chemical calculations. Modern computer simulations of the structures and characteristics of the N-doped PAHs were conducted by Dr Kubas and his team.
The research consortium keeps working to create better emitters for OLED panels that consume less energy. Read their entire study here.