Spin‐Coated Bismuth Vanadate Thin Film as an Alternative Electron Transport Layer for Light‐Emitting Diode Application

Abstract

This study describes the bismuth vanadate thin films (BVO) as an alternative electron transport layer for widely used LiF for the electron‐only device (EODs) application. The BVO thin film is spin‐coated on a glass substrate as a function of solution concentration. The X‐ray diffraction pattern of the film deposited from 10 × 10−3m (BVO1) to 150 × 10−3m (BVO4) solution concentration possesses the BiVO4 phase with a tetragonal structure, whereas the film deposited at 200 × 10−3m (BVO5) shows the Bi2V4O11 phase with an orthorhombic structure. The surface morphology of the films confirms nanoparticle formation with the lower surface roughness. The UV–visible studies show the average transmittance of the films decreases with increasing solution concentration and the maximum average transmittance of 86% is obtained in BVO1 film. This oxygen vacancy promotes the charge transfer process very effectively. The EODs fabricated using BVO1 film (BiVO4 phase) exhibits the maximum current density of 59.2 mA cm−2 with a turn‐on voltage of 4.09 V, whereas the EOD device fabricated using BVO5 film (Bi2V4O11 phase) possesses the current density of 5.9 mA cm−2 with a turn‐on voltage of 4.09 V. Hence, the fabricated EODs using the BVO electron transport layer shows applicability in the OLED device.

Enhanced Solar‐Photo(Electro)catalysis of Microwave‐Hydrothermal Synthesized BiVO4, ms‐BiVO4/Reduced Graphene Oxide/Ag3PO4 Nanohybrid: Crystalline Phase‐Dependent Interfacial Charge Carrier Dynamics

“…We found that the anticipated TC hkl values of B‐2 and B‐1 photoanode films are textured along (040) and (112) planes with values of 1.4 and 1.09 (Figure S3c, Supporting Information), which proves that the increase in TC value facilitates the grain growth in fovorable planer direction and the decrease in grain boundries. [ 39,40 ]…”

“…We found that the anticipated TC hkl values of B-2 and B-1 photoanode films are textured along (040) and ( 112) planes with values of 1.4 and 1.09 (Figure S3c, Supporting Information), which proves that the increase in TC value facilitates the grain growth in fovorable planer direction and the decrease in grain boundries. [39,40] Raman studies have been taken to analyze the microstructure and phase confirmation of B-1, B-2, B-4, and GB-4 photoanodes (Figure 1f ). Raman shift at 212, 325, 367, 644, 710, and 826 cm À1 in B-2, B-4, and GB-4 films assured ms-BiVO 4 crystalline phase.…”