Photocatalytic evaluation of self-assembled porous network structure of ferric oxide film fabricated by dry deposition process

• Published in: Materials chemistry and physics Vol. 181; pp. 241 - 247
• Main Authors: Park, Yunchan, Kim, Hyungsub, Lee, Geon-Yong, Pawar, Rajendra C., Lee, Jai-Sung, Lee, Caroline Sunyong
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.09.2016
• Subjects: Ceramic; Coating; Electrochemical properties; Porous materials; Ceramic; Electrochemical properties; Coating; Porous materials
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2016.06.055

Ferric oxide powder in the alpha phase (α-Fe2O3) was deposited on an aluminum oxide (Al2O3) substrate by a nanoparticle deposition system using the dry deposition method. X-ray diffraction (XRD) images confirmed that the phase of the deposited α-Fe2O3 did not change. The deposited α-Fe2O3 was characterized in terms of its microstructure using scanning electron microscopy (SEM). A porous network microstructure formed when small agglomerates of Fe2O3 (SAF) were deposited. The deposition and formation mechanism of the microstructure were investigated using SEM and three-dimensional (3D) profile analysis. First, a dense coating layer formed when the film was thinner than the particle size. After that, as the film thickness increased to over 5 μm, the porous network structure formed by excavating the surface of the coating layer as it was bombarded by particles. Rhodamine B (RhB) was degraded after 6 h of exposure to the Fe2O3 coating layer with SAF, which has good photocatalytic activity and a high porous network structure. The kinetic rate constants of the SAF and large agglomerates of Fe2O3 (LAF) were calculated to be 0.197(h−1) and 0.128(h−1), respectively, based on the absorbance results. Using linear sweep voltammetry, we confirmed that the photoelectric effect occurred in the coating layer by measuring the resulting current under illuminated and dark conditions. Self-assembled porous photocatalytic film fabricated by dry deposition method for water purification. [Display omitted] •Different sizes of Fe2O3 agglomerates were used to form porous network structure.•Fe2O3 agglomerate particles were deposited using solvent-free process.•Self-assembled porous network microstructure formed better with small agglomerates of Fe2O3.•Fabricated porous network structure showed its potential to be used for photocatalyst.