With the limited fossil fuel reserves and the environmental (e.g. global warming prospects), the appeal for large scale exploitation of clean renewable energy sources such as wind and solar is greater than ever. During the past few decades extensive efforts have been devoted to increasing the efficiency and lowering the cost of solar cells using new materials and optimized designs. Although solar panels are becoming more popular, they constitute a very small fraction (< 0.1%) of the overall energy production in the United States. This is mainly due to the relatively high cost of the existing photovoltaic solar generators and the large initial investment requirement which remain the main drawback for widespread use of solar energy. Photo-conversion in most of the existing commercialized solar panels is performed by a solid phase semiconductor PN junction. Formation of the optimal PN junctions on semiconductor substrates requires extensive and costly thermal processing occasionally raising the question of whether a solar cell can generate the energy spent for its fabrication over its lifetime.
Photo-electrochemical cells (PEC) on the other hand can potentially harvest the solar energy at a much lower cost than the conventional solid state PVs. Photo-conversion in PECs is performed by the junction formed between a semiconductor electrode and an electrolyte eliminating the need for solid state PN junctions. However, despite tremendous potentials, the amount of research performed on PEC solar cells, especially using silicon electrodes is very limited. This project has been focused on the implementation of the Silicon as a Photo-Cathode and eliminating the need to deposit additional protective coating such as nano-metals and polymers to increase the electrode life time.
- B. Tousifar, and S. Pourkamali, “Characterization of a very low-cost silicon cathode-zinc electrolyte solar cell,” IEEE Photovoltaic Specialists Conference (PVSC), 2010.