Structural characterizations of organic-based materials with extensive mechanoluminescence properties

The organic mechanoluminescent (ML) material europium-doped dibenzoylmethide triethylammonium (EuD4TEA) is known as a triboluminescent material. Our group has synthesized a novel ML material with the addition of 1-ethenylpyrrolidin-2-one [(polyvinylpyrrolidone) (PVP)], which changed the ligand of the mechanoluminescent material. This research investigated the ML material structure, molecular orbital electron distributions of the ligands, ML mechanism and enhancement in the photoluminescence (PL) intensity with PVP. For the first time, the ML material structure was characterized using nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Gaussian DFT/B3LYP/6-31G(d,p) software. The ML properties were characterized using a Hamamatsu Photonic Multichannel Analyzer (PMA). The material can be applied to the real-time visualization of the stress field near the tip of a crack, an ML light source, determination of laser and ultrasonic powers, secret message writing and earthquake detection sensors.