Synthesis and photoluminescence properties of polycarbazole/tin oxide (PCz/SnO2) polymer nanocomposites

FRET mechanism to enhance the quantum yield of the PCz/gC3N4 nanocomposite, an emissive material for OLED applications

Conjugated polymers such as polycarbazole (PCz) have captivated more attention than other carbazole-based derivatives due to their superior electrical and optical properties. Accordingly, we synthesized PCz/gC3N4 nanocomposites via the in situ polymerization method using FeCl3 as the oxidative reagent. The synthesized nanocomposites were subjected to characterization techniques to examine their optical and electrical parameters and decide whether the materials were suitable as emissive materials. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) were carried out to ascertain the crystalline or amorphous nature, surface interactions, and functional groups present in them. The surface microstructural and topographical investigations were conducted using field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (HRTEM) techniques. Optical parameters, such as refractive index ∼2.06, optical absorbance, optical band energy ∼2.77 eV, and the photoluminescence emission range, were studied using UV-Visible and photoluminescence spectrometry. The theoretical relative emission quantum yield of ∼67.9% and 87.7% energy transfer from the donor to the acceptor ion via the Förster energy transfer mechanism are illustrated by the PL data. The Förster energy transfer mechanism has been elaborated. The carrier mobility ∼32.03 m2 V-1 S-1, sheet resistance ∼1.6977 × 102 Ω m, carrier density ∼11.96 × 1014 cm-3 and conductivity ∼5.90 × 10-3 S cm-1 were computed using Hall effect measurements. The dielectric constant, dielectric loss, and IV characteristic curve were estimated by the LCR and Four-probe IV measurement methods. The high PL emission intensity, CIE coordinates in the blue emission region, and the CCT value indicate that it is a suitable emissive layer material for OLED applications.

Ternary Electrical Memory Devices Based on Polycarbazole: SnO2 Nanoparticles Composite Material

In this paper, a D–A polymer (PIB) containing carbazole as the donor group in the main chain and benzimidazole benzisoindolinone as the acceptor group was synthesized by Suzuki reaction. The Suzuki reaction, also known as the Suzuki coupling reaction, is a relatively new organic coupling reaction in which aryl or alkenyl boronic acids or boronic acid esters react with chlorine, bromine, iodoaromatic hydrocarbons or alkenes under the catalysis of zerovalent palladium complexes cross-coupling. A series of devices were fabricated by a spin-coating approach, and the devices all exhibited ternary resistance switching storage behavior. Among them, the composite device with the mass fraction of SnO₂ NPs of 5 wt% has the best storage performance, with a threshold voltage of −0.4 V and a switching current ratio of 1:10^1.5:10^4.5. At the same time, the current of the device remained stable after a 3-h test. Furthermore, after 10³ cycles, the current has no obvious attenuation. The device has good stability and continuity. Moreover, the conduction mechanism is further revealed. Inorganic nanoparticle composite devices have splendid memory performances and exhibit underlying application significance in storing data.