Perovskite Solar Cells
Introduction
Perovskite solar cells (PSCs) are a type of photovoltaic cell which include a perovskite structured compound, most commonly a hybrid organic-inorganic lead or tin halide-based material, as the light-harvesting active layer. These cells are potential candidates for new generation solar cells due to their high efficiency and low production costs.
History
The use of perovskites in solar cells was first reported in 2009 by Tsutomu Miyasaka and his team at the Toin University of Yokohama, Japan. The initial efficiency was reported to be 3.8%, which was significantly lower than the efficiencies of existing solar cell technologies. However, the efficiency of perovskite solar cells has improved rapidly, reaching over 25% in laboratory conditions by 2020.
Structure and Operation
Perovskite solar cells are typically composed of a perovskite structured compound as the active layer, sandwiched between two charge transport layers, and two electrodes. The perovskite structured compound, which is usually a hybrid organic-inorganic lead or tin halide-based material, absorbs light and generates pairs of electrons and holes. The charge transport layers, which can be organic or inorganic, help to separate the electrons and holes and transport them to the electrodes.
Efficiency
The efficiency of perovskite solar cells has increased rapidly since their development. The current record efficiency for a perovskite solar cell in laboratory conditions is over 25%, which is comparable to the efficiency of traditional silicon-based solar cells. However, the efficiency of perovskite solar cells can be affected by various factors, such as the quality of the perovskite layer, the choice of charge transport materials, and the cell architecture.
Stability
One of the main challenges for the commercialization of perovskite solar cells is their stability. While the efficiency of perovskite solar cells is high, they tend to degrade rapidly under normal operating conditions. This is mainly due to the instability of the perovskite materials, which can decompose under heat, light, and moisture. Various strategies have been developed to improve the stability of perovskite solar cells, such as the use of more stable perovskite materials, the incorporation of protective layers, and the optimization of the cell architecture.
Production
The production of perovskite solar cells involves several steps, including the preparation of the perovskite layer, the deposition of the charge transport layers, and the fabrication of the electrodes. The perovskite layer is typically prepared by a solution process, which involves the dissolution of the perovskite precursors in a solvent, the coating of the solution onto a substrate, and the crystallization of the perovskite material. The charge transport layers and the electrodes can be deposited by various techniques, such as spin coating, thermal evaporation, and sputtering.
Applications
Perovskite solar cells have potential applications in various areas, such as building-integrated photovoltaics, portable electronic devices, and solar-powered vehicles. Due to their high efficiency and low production costs, perovskite solar cells could potentially replace traditional silicon-based solar cells in the future. However, the commercialization of perovskite solar cells is currently hindered by their stability issues.
Future Perspectives
The future of perovskite solar cells depends on the progress in overcoming their stability issues and scaling up their production. With continuous research and development, it is expected that the efficiency of perovskite solar cells will continue to improve and their stability will be enhanced. In addition, the development of environmentally friendly and low-cost production methods will be crucial for the commercialization of perovskite solar cells.