Photoanodic Properties of Sol−Gel-Derived Fe₂O₃ Thin Films Containing Dispersed Gold and Silver Particles

Abstract

α-Fe2O3 films containing dispersed Au and Ag particles 5−20 nm in size were prepared on nesa silica glass substrates by the sol−gel method, using solutions of a mole ratio Fe(NO3)3·9H2O: (HAuCl4·4H2O or AgNO3):CH3COCH2COCH3:CH3OCH2CH2OH = 1:0.06:2:20 as the coating solution. The anodic photocurrent−potential characteristics and the action spectra were investigated in a three-electrode cell employing the film electrode as the working electrode. When the film electrode was illuminated with intense white light, the embedded metal particles did not affect the photoanodic properties of the electrode significantly. When the film electrode was illuminated with weak white light or weak monochromatic light, the metal particles, especially Au particles, enhanced the anodic photocurrent; the Au particles embedded in the electrode enhanced the quantum efficiency, IPCE, by about 8 times at a wavelength of 400 nm. Deposition of Au particles just on the surface of the Fe2O3 film also increased the photoanodic current, suggesting that the enhanced photocurrent is provided by the Au particles on the electrode surface, which are supposed to catalytically promote the transfer of the hole in the conduction band of Fe2O3 to the electrolyte.

Photoelectrocatalytic degradation of bisphenol A in aqueous solution using a Au–TiO2/ITO film

“…The XRD results showed that both anatase and rutile were present in the Au-TiO 2 /ITO films. In addition, the crystalline Au can only be found in the Au-TiO 2 /ITO films with a Au content higher than 1.5% as a broad peak at around 2 = 44 °, according to Watanabe et al [36]. [18,37,38].…”

α‐Fe2O3 Nanoflakes as an Anode Material for Li‐Ion Batteries

“…[2][3][4][5][6][7][8][9] In addition, it is possible for many of these oxides to intercalate-deintercalate Li ions into the layered (2D) or network (3D) structure. [1,3] In recent years, nanoparticles, nanotubes, and thin films of a-Fe 2 O 3 (hexagonal corundum structure) have been studied for their magnetic properties, [10] photoelectrochemical splitting of water to hydrogen, [11] photoanodic properties, [12] field-emission behavior, [13] use as potential gas sensors [14] and as electrodes for LIB applications. [14][15][16][17][18][19] Larcher et al [16] have shown that 0.5 moles of Li can be reversibly intercalated into nanoparticles (20 nm) of a-Fe 2 O 3 in the potential range 1.5-4.0 V (vs. Li).…”

Manufacture and investigation of nanoporous titanium oxide photoelectrodes

“…1 Introduction Efforts in the field of development of new technologies for manufacturing of nanostructured photoelectrodes and investigations of peculiar properties of their photoelectrochemical behaviour became especially more active in last years (see, in particular, [1][2][3][4]). Thin film photoelectrodes with nanoporous structure are desirable for photoelectrochemical splitting of water due to their large surface area and high catalytic activity.…”