Indium tin oxide random network interconnection in dye sensitized solar cells

• Main Author: Shimon.
• Other Authors: Wong Chee Cheong
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Materials::Energy materials
• Online Access: http://hdl.handle.net/10356/15329
• Institution: Nanyang Technological University

This project is aimed to provide comprehensive investigation on the photovoltaic energy conversion efficiency improvement by incorporating random network of interconnecting Indium Tin Oxide (ITO) structure in Titanium Dioxide (TiO2) based dye-sensitized solar cells (DSSC). This method requires shorter time, easier process and cheaper cost than other existing conductive path enhancement fabrication methods for DSSC. This research consisted of both simulation analysis and experimental investigation of the optimum ITO structure in a DSSC. A novel algorithm was developed to compute the optimal electron conductive paths in a DSSC based on statistical analysis of randomized ITO interconnection. As a result, experimental conditions and parameters, such as TiO2/ITO nanoparticles’ size and their relative concentration, can be predicted and optimized for improving DSSC’s efficiency. The simulation predicts a remarkable efficiency enhancement when 70% ITO content added at porosity 40% in the DSSC to as high as 3 times the value when pure TiO2 is used. The experimental work confirms the increasing trend of efficiency with increasing ITO content, e.g. efficiency of 2.907% at pure TiO2 was observed to be increased to 3.128% at 50% of ITO content with porosity reduction from 54% to 49%. The efficiency increment, though cannot be directly correlated to the simulation, suggests a possible efficiency enhancement with ITO addition into TiO2/ITO mixture. Other factors, such as film porosity and thickness, are also investigated and revealed strong conformation among the hypothesis, simulation and experimentation results. This project uniquely allows experimental parameters to be optimized with numerical analysis before carrying the experiment. Through this project, better understanding of ITO/TiO2 random mixture DSSC in terms of porosity, thickness, ITO content and particle size effect on efficiency of the cell are documented. Potential future works on the novel simulation work such as incorporation of other prevailing factors to suit experimental practicality and relevance into other related system are promising.