Dual-electron-enhanced effect in K-doped MoS few layers for high electrocatalytic activity as the counter electrode in dye-sensitized solar cells

• Published in: Chemical communications (Cambridge, England) England), 2022-09, Vol.58 (77), p.1857-186
• Main Authors: Yan, Yuna, Shen, Gang, Song, Rui, Hong, Kunquan
• Format: Article
• ISSN: 1359-7345; 1364-548X
• DOI: 10.1039/d2cc04021b

Designing counter electrodes (CEs) with high efficiency and understanding the mechanism of dye-sensitized solar cells (DSSCs) are still challenges. In this paper, we synthesized K-doped molybdenum disulfide (K-MoS 2 ) with few layers and it has a great enhancement effect on the electrocatalytic activity compared to pure MoS 2 CE and reference Pt CE. A dual electron-path model is proposed to explain the mechanism, which is supported by first-principles calculations. When an electron in MoS 2 is transferred to the triiodide, the K atoms can act as an electron reservoir to provide another electron in a short time to improve the catalytic activity. So the proposed dual-electron effect in this paper is helpful to understand the charge transfer mechanism on the interfaces of these CEs and may be crucial for obtaining high photoelectric efficiencies in DSSCs. The dual-electron-path-enhancement effect enhances the electrocatalytic activity.