Optical and morphological features of poly(vinyl carbazole)/ferrite composites for potential opto-electronic applications

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2021-11, Vol.127 (11), Article 855
• Main Authors: Tavares, Tiago B., de Sousa, Francisco F., Sales, Maria J. A., Paterno, Leonardo G., Paschoal, Waldomiro, Moreira, Sanclayton G. C.
• Format: Article
• Language: English
• Subjects: Applied physics; Blue shift; Carbazoles; Characterization and Evaluation of Materials; Condensed Matter Physics; Emission analysis; Emission spectra; Energy gap; Ferrites; Iron oxides; Machines; Manufacturing; Materials science; Morphology; Nanotechnology; Optical and Electronic Materials; Optical properties; Optoelectronics; Physics; Physics and Astronomy; Polyvinyl carbazole; Processes; Scanning electron microscopy; Spectrum analysis; Surfaces and Interfaces; Thin Films
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-021-04975-y

In this work, three composite films built upon poly(vinyl carbazole) (PVK) and Fe 3 O 4 , FeLiO 2 and (La 0.6 Sr 0.4 ) (Co 0.2 Fe 0.8 )O 3 (LSCF) ferrites were produced by sonication and drop-casting. The optical absorption, emission, and band gap properties of all samples were investigated using optical spectroscopy techniques and morphological analysis by scanning electron microscopy (SEM). After introducing the ferrites, the optical absorbance of PVK in the range between 280 and 400 nm increased, whereas its bandgap systematically reduced. On the other hand, emission spectra of PVK were broadened with all ferrites and blue-shifted only in the presence of FeLiO 2 . Meanwhile, PVK excited state lifetimes were significantly shortened, thereby suggesting the creation of donor/acceptor states in the bandgap, which ultimately suppress the PVK emission. Although SEM images showed the presence of aggregated ferrites, most of them were readily dispersed in the PVK matrix.