Hexagonal FeS nanosheets with high-energy (001) facets: Counter electrode materials superior to platinum for dye-sensitized solar cells

详细信息    查看全文

• 作者：Xiuwen Wang ; Ying Xie ; Buhe Bateer ; Kai Pan ; Yangtao Zhou ; Yi Zhang…
• 关键词：FeS nanosheets ; high ; energy facets ; counter electrode ; first ; principles calculation ; catalytic reduction
• 刊名：Nano Research
• 出版年：2016
• 出版时间：October 2016
• 年：2016
• 卷：9
• 期：10
• 页码：2862-2874
• 全文大小：2,613 KB
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Chinese Library of Science
  Chemistry
  Nanotechnology
  
• 出版者：Tsinghua University Press, co-published with Springer-Verlag GmbH
• ISSN：1998-0000
• 卷排序：9

文摘

The catalytic activity of materials is highly dependent on their composition and surface structure, especially the density of low-coordinated surface atoms. In this work, we have prepared two-dimensional hexagonal FeS with high-energy (001) facets (FeS-HE-001) via a solution-phase chemical method. Nanosheets (NSs) with exposed high-energy planes usually possess better reaction activity, so FeS-HE-001 was used as a counter electrode (CE) material for dye-sensitized solar cells (DSSCs). FeS-HE-001 achieved an average power conversion efficiency (PCE) of 8.88% (with the PCE of champion cells being 9.10%), which was almost 1.15 times higher than that of the Pt-based DSSCs (7.73%) measured in parallel. Cyclic voltammetry and Tafel polarization measurements revealed the excellent electrocatalytic activities of FeS-HE-001 towards the I₃–/I– redox reaction. This can be attributed to the promotion of photoelectron transfer, which was measured by electrochemical impedance spectroscopy and scanning Kelvin probe, and the strong I₃– adsorption and reduction activities, which were investigated using first-principles calculations. The presence of high-energy (001) facets in the NSs was an important factor for improving the catalytic reduction of I₃–. We believe that our method is a promising way for the design and synthesis of advanced CE materials for energy harvesting.