3D Hierarchical Bi2S 3 Nanostructures by Polyvinylpyrrolidone (PVP) and Chloride Ion-Assisted Synthesis and Their Photodetecting Properties.

Taotao Ding,Changqing Chen,Wu Tian,Jiangnan Dai,Yanyan Fang,Jin Wang,Juan Xu,Kaifu Huo

doi:10.1186/s11671-015-0993-1

Abstract

A solvothermal method has been employed to synthesize bismuth sulfide (Bi2S3) with three-dimensional (3D) hierarchical architectures. The influences of different types of surfactants and Cl− species on the size and morphology were investigated. A possible formation mechanism was also proposed on the basis of time-dependent experiments. The photoresponse properties show that the conductivity of Bi2S3 micro-flowers is significantly enhanced and the photocurrent is approximately two orders of magnitude larger than the dark current. The response and decay times are estimated to be 142 and 151 ms, respectively. It is expected that hierarchical architectures Bi2S3 may provide a new pathway to develop advanced nanomaterial for high-speed and high-sensitivity photoelectrical switches and photodetecting devices.

Highlights

Bismuth sulfide (Bi2S3) that is an important member of group V–VI binary semiconductors, has drawn increasing attention in solar cells [1], photodetectors [2,3,4,5,6,7,8,9,10], gas sensors [11], Schottky diode [12], lithium-ion battery [13], X-ray computed tomography imaging (CT) [14], and thermoelectric devices [15]
The results show that the photocurrent is enhanced by two orders of magnitude compared with the dark current and the response time and decay time are estimated to be 142 and 151 ms, respectively, indicating promising applications of the as-prepared 3D hierarchical Bi2S3 for photodetecting and photoelectric switches
The pattern shown at the bottom is the standard X-ray powder diffraction (XRD) card of Bi2S3 (JPCDS no. 17-0320). b–d The full spectra, Bi2f, and S2s region of the X-ray photoelectron spectra (XPS) spectrum of V-Bi2S3, respectively kλ cosθ where D is the average crystalline size, k is a constant whose value is typically 0.9 of non-spherical crystals, B is the full width at half maximum (FWHM) of the diffraction peak that has the maximum intensity in the diffraction pattern, λ is the wavelength of incident X-ray beam (0.154184 nm), and θ is diffraction angle or Bragg angle

Summary

Introduction

Bismuth sulfide (Bi2S3) that is an important member of group V–VI binary semiconductors, has drawn increasing attention in solar cells [1], photodetectors [2,3,4,5,6,7,8,9,10], gas sensors [11], Schottky diode [12], lithium-ion battery [13], X-ray computed tomography imaging (CT) [14], and thermoelectric devices [15]. There is no report to prepare Bi2S3 nanostructures by introducing Cl− to monitor the morphology of Bi2S3 during solvothermal process. Jiang et al reported that they had synthesized flower-like Bi2S3 by an ionic liquid-assisted templating route [30]. In 2010, the flower-like Bi2S3 had been synthesized via a hydrothermal method by Tang et al [31]. The similar Bi2S3 had been obtained by Wang et al via the same hydrothermal method and assembled into the dye-sensitized solar cells with a good performance [32]. Chen et al reported that they had synthesized ultrathin Bi2S3 nanosheets via an organometallic synthetic route [10]

Methods

Results

Conclusion