Adjusting Porosity and Pore Radius of Electrodeposited ZnO Photoanodes. Issue 9 (15th March 2019)

• Record Type: Journal Article
• Authors: Nguyen, Thi Hai Quyen; Ruess, Raffael; Schlettwein, Derck
• Is Part Of: Journal of the Electrochemical Society. Volume 166:Issue 9(2019)
• Page Start: B3040
• Page End: B3046
• Publication Date: 2019-03-15
• Subjects: Electrodeposition - semiconductors -- Films -- Photoelectrochemistry -- dye-sensitized solar cells -- pore structure -- zinc oxide; Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/2.0101909jes
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : The optimization of the porosity and pore radius of ZnO for the application in dye-sensitized solar cells is essential to enhance the cell performance. Porous ZnO films were fabricated by electrodeposition in the presence of eosin Y or in combination with eosin B which was used as a structure directing agent (SDA) for the first time. The influence of the deposition time and the SDA concentration on film porosity and pore radius was characterized by a combined electrochemical and atomic absorption spectroscopy analysis, and confirmed by gas sorption, optical spectroscopy and scanning electron microscopy. The combination of eosin Y with eosin B as SDA results in porous ZnO films with larger pore radius compared to the films prepared with eosin Y only. The larger pores showed a significantly decreased diffusion impedance leading to an increased photocurrent less hindered by mass transport. Successful application of these new ZnO films in dye-sensitized solar cells confirmed improved pathways for large complex ions as redox shuttles through the ZnO pore structure.