Investigating various copper oxides-based counter electrodes for dye sensitized solar cell applications

Abstract

Due to the rapid increase in their efficiencies, third generation photovoltaics rose to prominence in recent years, and became serious competitors to conventional silicon based and thin film solar cells. This work investigates various techniques to grow and/or deposit copper oxide (CuO) on a copper substrate for utilization as a counter electrode in dye sensitized solar cell (DSSC) applications. Copper has many attractive thermal, electrical and mechanical properties and is widely used in solar thermal applications, but its use is limited in solar photovoltaic cells. The experimental results reported herein have proven the success of growing an intrinsic copper oxide layer on a pure copper substrate. Among the methods, the chemical ageing process followed by heat treatment has resulted in a homogenous and adherent oxide layer that attenuated the electronic conductivity and chemical reactivity of pure, bare copper electrodes. These electrodes are incorporated into solar cells that are constructed and tested against a platinum reference cell. The cells showed comparable short circuit current to their platinum counterparts, with efficiencies of 0.2% compared with 0.5% for platinum under the same conditions. The copper counter electrode with the CuO deposition exhibited good promise, especially when comparing figures of merit (power generated/price) as a cheap and effective alternative to platinum in third generation solar cell applications.