fotoluminescentiekwantumopbrengst
Fotoluminiscencia, or photoluminescence, is the emission of light by a material after it absorbs photons. The process begins when a substance absorbs energy, promoting electrons to higher electronic states, and ends with the release of part of that energy as photons as the system relaxes to lower energy states. Photoluminescence occurs without the need for external electrical current and is driven by optical excitation.
Two primary forms are fluorescence and phosphorescence. In fluorescence, emission occurs rapidly, typically within nanoseconds, and
Mechanistically, after absorption a molecule undergoes vibrational relaxation to the lowest excited singlet state (S1). Radiative
Materials that exhibit photoluminescence include organic dyes and polymers, inorganic phosphors, quantum dots, and perovskite-based systems.
Applications span lighting and displays (LEDs and OLEDs), fluorescent labeling and bioimaging, chemical and biological sensing,