Flexible fiber-shaped CuInSe2 solar cells with single-wire-structure: Design, construction and performance

Fiber-shaped solar cells (FSCs) have attracted increasing interest in recent years due to their numerous advantages. Herein we report the first prototype of highly flexible all-solid-state single-wire FSCs by using CuInSe2 (CIS) as the model photoactive semiconductor. CIS layer is electrodeposited on a flexible Mo wire as the substrate. Subsequently, CdS, ZnO and ITO layers are orderly deposited on the Mo/CIS wire, and each upper layer ensures full contact with the underlying layer, resulting in an excellent structural uniformity along circumference of the FSC. This Mo/CIS/CdS/ZnO/ITO single-wire FSC exhibits a power conversion efficiency of 2.31%, which is one of the highest values in all reported FSCs. More importantly, the present all-solidstate single-wire FSC exhibits stable conversion efficiency (2.16-2.32%) during rotation (0 similar to 360 degrees), bending (0 similar to 360 degrees) and long-time aging (stored at 60 degrees C for 600 h). processes, which makes it possible to fabricate very long single-wire FSC with stable efficiency for weaving large-area devices and/or the stereoscopic cell textiles. Our method provides a new and general approach for fabricating flexible single-wire FSC with various kinds of photovoltaic semiconductor materials, and it also would be applicable to develop other flexible electronic circuits. (C) 2012 Elsevier Ltd. All rights reserved.