Development and evaluation of low cost dye sensitized solar cells for energy conversion applications

Abstract

Worldwide power consumption is expected to be double in the next three decades. Presently, the global energy supplies depend predominantly on fossil fuels (e.g. oil, natural gases and coal) and nuclear technologies. The ever increasing power demands results in pressure on the conventional energy sources. The fossil resources are in limited quantity which may exhaust in near future. Consequently, there is a need to search an alternative energy sources which can be environment friendly and reliable. Sun is one of the biggest sources of renewable energy, the power from the sun is intercepted by earth is about 1.8×1011 MW, is many thousands times greater than the current power consumption from all sources. Hence, the conversion of solar energy into electrical energy became important. Solar cells are effective devices in conversion of solar energy into electricity exclusive of any environmental pollution, and which address the ever growing energy demands. Solar cells are dominated by expensive solid-state photovoltaic cells. To develop an alternate efficient low cost solar cells are necessary. The dye sensitized solar cell (DSSC) is an interesting emerging technology, due to low-cost, easy to fabricate and environmentally pleasant than the conventional solid-state photovoltaic devices. The DSSC is mainly based on the cheap starting materials and inexpensive fabricate process and are likely to be a significant contributor to the future commercial photovoltaic technology portfolio. This offers numerous areas for improvement, both electronically and optically. The main components in DSSC is photo electrode (dye adsorbed nano crystalline TiO2 on FTO), counter electrode (platinum (Pt) coated on FTO) and an electrolyte of redox couple (I - / and#8722; 3 I ). The counter electrode plays an significant role in DSSC. Generally, counter electrode is prepared with a thin layer of platinum (Pt) coated on FTO (fluorine doped tin oxide) and is used to catalyze the cathodic reduction of and#8722; 3 I ions and redox couple regeneration in DSSC.