Open Access Nano Express

3-D solar cells by electrochemical-deposited Se layer as extremely-thin absorber and hole conducting layer on nanocrystalline TiO2 electrode

Duy-Cuong Nguyen1, Souichirou Tanaka1, Hitoshi Nishino2, Kyohei Manabe2 and Seigo Ito1*

Author Affiliations

1 Department of Electric Engineering and Computer Sciences, University of Hyogo, Shosha 2167, Himeji, Hyogo, 671-2280, Japan

2 Energy Technology Laboratories, Osaka Gas Co. Ltd, 6-19-9, Torishima, Konohana-Ku, Osaka, 554-0051, Japan

For all author emails, please log on.

Nanoscale Research Letters 2013, 8:8  doi:10.1186/1556-276X-8-8

Published: 3 January 2013

Abstract

A three-dimensional selenium solar cell with the structure of Au/Se/porous TiO2/compact TiO2/fluorine-doped tin oxide-coated glass plates was fabricated by an electrochemical deposition method of selenium, which can work for the extremely thin light absorber and the hole-conducting layer. The effect of experimental conditions, such as HCl and H2SeO3 in an electrochemical solution and TiO2 particle size of porous layers, was optimized. This kind of solar cell did not use any buffer layer between an n-type electrode (porous TiO2) and a p-type absorber layer (selenium). The crystallinity of the selenium after annealing at 200°C for 3 min in the air was significantly improved. The cells with a selenium layer deposited at concentrations of HCl = 11.5 mM and H2SeO3 = 20 mM showed the best performance, resulting in 1- to 2-nm thickness of the Se layer, short-circuit photocurrent density of 8.7 mA/cm2, open-circuit voltage of 0.65 V, fill factor of 0.53, and conversion efficiency of 3.0%.

Keywords:
3-D solar cells; Nanocrystalline TiO2 electrode; Se layer