Binder-Free Graphene Organogels as Cost-Efficient Counter Electrodes for Dye-sensitized Solar Cells. (10th February 2016)

• Record Type: Journal Article
• Authors: Pan, Dengyu; Feng, Chuanqi; Wang, Liang; Liu, Yuan; Chen, Zhiwen; Shi, Wenyan; Li, Zhen
• Is Part Of: Electrochimica acta. Volume 191(2016)
• Page Start: 946
• Page End: 953
• Publication Date: 2016-02-10
• Subjects: Graphene -- Organogels -- Solvent-exchange -- Dye-sensitized solar cells -- Counter electrodes; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.01.131
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: Graphene organogels (GOGs) filled with organic electrolytes may function as high-activity, low-cost electrodes for energy conversion and storage devices such as Li ion batteries, supercapacitors, and dye-sensitized solar cells (DSSCs), because of their ideal electron-transport and ion-diffusion pathways through an interconnected 3D porous framework self-assembled from highly conductive and high-specific-area graphene sheets. Here, graphene hydrogels prepared by a modified hydrothermal method are converted into organogels with a specific surface area up to ∼1298 m 2 g −1 by a simple solvent-exchange approach, and pressed onto titanium meshes to form GOG films as economical, wearable counter electrodes for DSSCs. Without optimizing TiO2 photoanodes, GOG-based DSSCs show a markedly enhanced short-circuit current density (16.34 mA cm −2 ) and thus an impressive power conversion efficiency of 7.2%, higher than those using graphene aerogels (11.6 mA cm −2, 5.9%) and commercial Pt films (10.2 mA cm −2, 5.9%) as counter electrodes under otherwise identical conditions. The improved efficiency is ascribed to a substantial reduction in charge-transfer resistance and series resistance, which is correlated with the high conductivity and high specific area of GOGs.