An all carbon counter electrode for dye sensitized solar cells

This article describes the design and operation of a dye sensitized solar cell with an all carbon counter electrode and plastic electrolyte. For the construction of the counter electrode, the conventional thin platinum catalytic layer was replaced by a novel large-effective-surface-area polyaromatic hydrocarbon (LPAH) film, and the fluorine doped tin oxide substrate was replaced by a graphite film. In this way the internal resistance of the cell was substantially reduced and the cell efficiency can reach nearly 9% using the masked frame measurement technique. To achieve such an efficiency, a series of experiments was carried out to assure that the LPAH layer possesses superior catalytic activity and energy efficiency compared to the commonly used carbon black. To this end a unique LPAH layer synthesis technique was developed. It involved the production of LPAH from a hydrogen arc along with the use of an amphiphilic triblock copolymer (P123) to improve the suspendability of LPAH to form a homogeneous catalytic layer. This layer was then attached to a graphite film to form the counter electrode for the dye sensitized solar cell. Details of the properties of the LAPH and the newly designed solar cell are reported herein.