Image Credits: Photos.com
Efficient solar energy conversion with photovoltaic cells requires materials that can harness solar photons absorbed in a wide spectral range from visible to infrared regions, and can convert most incident photons into electrical energy effectively.
The evolution of perovskite materials is transforming the photovoltaic field with their efficient charge extraction and ability to absorb solar photons from a broad spectral range.
Perovskite materials have been implemented within solar cell production since 2009. Research has been carried out on perovskites at a number of laboratories. A research team working at Oxford University recently discovered that perovskite materials can be used as an alternative to thin film silicon cells by employing the same processing methods.
The team has developed organometaltrihalide perovskite semiconductors that can be used as a light-absorbing element in dye-sensitized solar cells. These semiconductors consist of a film made of titanium-dioxide nanoparticles which are coated with perovskites. The absorption of light by the perovskite layer generates charge carriers such as electrons and holes. The electrons and holes are then transferred to transport materials which in turn carry the charges to the electrodes.
Research carried out by Nanyang Technological University scientists includes the study of unique characteristics of perovskite as solar cell materials. Researchers utilized ultra-fast lasers to determine how fast perovskite responds to light in quadrillionths of a second.
The results proved that perovskite gets deposited on the solar cells without any imperfections or flaws, which allows the electrons, generated through sun light, to flow freely. This process could help with the manufacture thick solar cells that absorb more light and generate more electricity.
The key benefits of perovskite solar cells include:
- Light weight
- High flexibility
- Innovative architectural design owing to the ability of perovskite to generate multiple translucent colors
- Inexpensive to manufacture
- Ability to achieve 20% solar cells efficiency
Perovskite solar cells are cheaper to produce and generate almost as much power traditional thin film solar cells. (Image Credits: NTU)
The development of nanomaterial-based photovoltaic cells as next-generation photovoltaics is mainly due to their simple design procedures under normal conditions. Significant improvements have already been made in analyzing the mechanism of solar cells and developing new strategies to enhance their efficiency.
The recent emergence of perovskite-based materials has further increased the interest of researchers to develop thin-film solid-state solar cells.
With the demand for high efficiency, economically viable solar cells has been the primary driving force for exploring next-generation solar cells. Perovskite solar cells are simple and inexpensive. With further research on optimizing the device design and film-deposition parameters, researchers expect perovskite thin film solar cells to offer more advantages than other conventional thin film photovoltaic cells in the future.
Converting solar energy into a clean, practical alternative power source will require highly efficient and inexpensive devices that generate electrical power from solar irradiation.
Oxford Photovoltaics recently announced a new breakthrough efficiency within their perovskite solar cells of 15.4%. Most notably, is that this was done without using Mesoporous Titanium Dioxide as a semiconductor.
Dr Henry Snaith, Founder and Chief Scientific Officer for Oxford Photovoltaics stated, "Our plan was to continuously optimise our perovskite solar cells towards a goal of more than 20% efficiency but these results are ahead of expectations. I see no reason why we can’t aim higher now and accelerate the transfer of our technology into production.”
Perovskite-based solar cells are revolutionizing the photovoltaic field with their simple and low-cost fabrication methods, promising photovoltaic efficiencies and wide spectral absorption range.
Sources and Further Reading
- Perovskites for dramatically cheaper PV – pv magazine
- Team of physicists find perovskite can be used in conventional solar cell architecture – Phys.org
- Easy-To-Manufacture, Thin-Film Solar Cell With Higher Than 15% Conversion Efficiency Created From Perovskites - CleanTechnica
- NTU scientists make breakthrough solar technology - Nanyang Technological University , Oxford PV reveals breakthrough in efficiency of new class of solar cell