Nanostructured Bi2S3/WO3 heterojunction films exhibiting enhanced photoelectrochemical performance

Abstract

To improve the photoelectrochemical activity of WO 3 , Bi 2 S 3 /WO 3 heterojunction films were designed by coupling WO 3 films with varying amounts of urchin-like Bi 2 S 3 nanospheres. The WO 3 films were composed of WO 3 nanoprism arrays, which were synthesized using a solvothermal method. After coating a single layer of Bi 2 S 3 on top of the WO 3 film, the resulting Bi 2 S 3 /WO 3 heterojunction film showed enhanced photoelectrochemical activity. At 1.2 V vs. Ag/AgCl, the initial photocurrent density of the Bi 2 S 3 /WO 3 heterojunction film with one layer of Bi 2 S 3 was 1.33 mA cm À2 in 0.1 M Na 2 SO 4 and 1.19 mA cm À2 in a 0.2 M NaCl mixed water-ethanol solution, which was 40% and 32% higher than the bare WO 3 film under the same conditions, respectively. The optimal number of Bi 2 S 3 layers for coupling with the WO 3 film was found to be 3 layers, which had the highest photocurrent density and IPCE values. The photoelectrochemical activity of Bi 2 S 3 /WO 3 heterojunction film was not stable for water oxidation due to photocorrosion in aqueous electrolyte, but it was stable in the NaCl mixed waterethanol solution and a non-aqueous solution containing iodide/triiodide as a redox couple. The origin of enhanced photoelectrochemical activity of the Bi 2 S 3 /WO 3 heterojunction film was primarily ascribed to the band potential matching between WO 3 and Bi 2 S 3 , which is advantageous for charge separation.

Tungsten-based nanomaterials (WO 3 & Bi 2 WO 6 ): Modifications related to charge carrier transfer mechanisms and photocatalytic applications

“…The modification of WO 3 with metal sulfides like CdS [164] or Bi 2 S 3 [165] resulted in extended visible light response and conventional charge transfer from metal sulfides to WO 3 CB.…”

Layer-controlled growth of MoS2 on self-assembled flower-like Bi2S3 for enhanced photocatalysis under visible light irradiation

“…6 Generally, the semiconductor that is incorporated as a cocatalyst to construct such a self-established heterojunction should possess good electric conductivity, a suitable energy structure and excellent electrochemical activity. [7][8][9][10][11] As a typical layered metal sulfide, MoS 2 has drawn increasing attention because of its layered structure similar to that of graphene, which is composed of three atom layers stacked together through Van der Waals interactions. 12,13 Such a two-dimensional (2D) layeredcrystal structure provides convenient electron transfer and many active sites for interfacial adsorption.…”

Photoelectrochemical biosensor for highly sensitive detection of microRNA based on duplex-specific nuclease-triggered signal amplification

“…Fig. 1 SEM images (a, b) and XRD pattern (c) of Bi 2 S 3 nanorods and Bi 2 S 3 -AuNPs Electrode characterization and detection feasibility assay It has been reported that the PEC response can be increased when the electrode was irradiated from the backside than the frontside [29]. For increasing the detection sensitivity, we investigated the effect of irradiation direction on the PEC response of Bi 2 S 3 /ITO.…”