Are you an EPFL student looking for a semester project?
Work with us on data science and visualisation projects, and deploy your project as an app on top of Graph Search.
Cobalt sulphide (CoS) films are potentiodynamically deposited on fluorine-doped tin oxide (FTO) coated glass substrates employing one, three and five sweep cycles (CoS-I, CoS-III and CoS-V respectively). Analysis of the CoS-III film by impedance spectroscopy reveals a lower charge transfer resistance (R-CT) than that measured for Pt CE (0.75 Omega cm(-2) and 0.85 Omega cm(-2), respectively). The CoS films are used as counter electrodes (CE) in dye-sensitized solar cells (DSSCs) featuring the combination of a high absorption coefficient organic dye (C218) and the cobalt-based redox electrolyte Co(bpy)(3). DSSCs fabricated with the CoS-III CE yield the highest short-circuit current density (J(SC)) of 12.84 mA cm(-2), open circuit voltage (V-OC) of 805 mV and overall power conversion efficiency (PCE) of 6.72% under AM 1.5G illumination (100 mW cm(-2)). These values are comparable to the performance of an analogous cell fabricated with the Pt CE (PCE = 6.94%). Owing to relative lower cost (due to the inherit earth abundance of Co) and non-toxicity, CoS can be considered as a promising alternative to the more expensive Pt as a CE material for next-generation DSSCs that utilize organic dyes and cobalt-based redox electrolytes. (C) 2014 Elsevier B.V. All rights reserved.
Shaik Mohammed Zakeeruddin, Jean-David Décoppet
Ulf Anders Hagfeldt, Thomas Moehl, Kazuteru Nonomura, Lorenzo Veronese
Shaik Mohammed Zakeeruddin, Jacques-Edouard Moser, Yuhang Liu, Ulf Anders Hagfeldt, Ladislav Kavan, Jingshan Luo, Chenyi Yi, Yiming Cao, Yasemin Saygili, Weiwei Zhang, Yinghui Wu, Heewon Bahng