Formamidinium lead iodide is a very good material for photovoltaic cells, but getting the correct and stable crystal structure is a challenge. The techniques developed so far have produced rather poor results. However, University of Groningen scientists, led by Professor of Photophysics and Optoelectronics Maria Antonietta Loi, have now cracked it – using a blade and a dipping solution.
The results were published in the journal Nanoscale on 15 March 2019.
Formamidinium lead iodide (FAPbI3) is a perovskite, a crystal with a distinctive structure. Perovskites are named after a mineral that has the chemical formula ABX3. In an idealized cubic unit cell, the X position is occupied by anions that form an octahedron with a central cation in the B position while the corners of the cube are occupied by the A position cations (see picture).
‘This formamidinium lead iodide material has very good characteristics, but the A position formamidinium ion causes instability in the structure,’ explains Loi. 3D films made from this material most often turn out to be a mixture of a photoactive and a photoinactive phase, the latter being detrimental to the final application. Loi therefore set her PhD student Sampson Adjokatse to work to find a solution.
After trying different strategies, he found one that worked. ‘And most importantly, one that is scalable and could be used for industrial production,’ says Loi. After all, solar cells must be produced in large panels and it is very important to find a good and cheap technique to do so.
Adjokatse started with a different perovskite, in which the formamidinium was replaced by a larger 2?phenylethylammonium molecule, and in doing so formed a 2D perovskite. This material was deposited as a thin film using the ‘doctor-blade’ technique, related to techniques widely used in industrial processes such as printing.
‘Basically, you spread the material onto a substrate using a blade,’ explains Adjokatse. The blade can be set to produce a film with a thickness of around 500 nanometres, creating the 2D perovskite layer. ‘The important point is that these films are very smooth with large crystalline domains of up to 15 micrometres,’ says Adjokatse. The smooth 2D films based on 2-phenylethylammonium lead iodide were used as a template to produce 3D formamidinium lead iodide films.
This was achieved by dipping the 2D film in a solution containing formamidinium iodide. This resulted in the growth of a 3D film through ‘cation exchange’, where formamidinium took the place of 2?phenylethylammonium. ‘These films show much higher photoluminescence compared to reference 3D formamidinium lead iodide films and show increased stability when exposed to light or moisture,’ says Loi. ‘This means that we now have a method for the production of high-quality films for perovskite solar cells using an industrially scalable technique.’
Learn more: Making solar cells can be like buttering bread
The Latest on: Perovskite solar cells
[google_news title=”” keyword=”perovskite solar cells” num_posts=”10″ blurb_length=”0″ show_thumb=”left”]
via Google News
The Latest on: Perovskite solar cells
- Scientists testing ‘miracle material’ for power generation in space encouraged by results: ‘This shift could redefine the solar industry landscape’on March 3, 2024 at 2:30 am
Perovskite solar cells could be the next big thing when it comes to clean energy, offering improvements in weight, flexibility, and range of applications compared to their silicon cousins, as ...
- Pusan National University Researchers Improve the Stability of Perovskite Solar Cellson March 1, 2024 at 5:37 am
2024 /PRNewswire/ -- Perovskite solar cells are thought of as the strongest contender to replace the conventional silicon solar cells in next-generation photovoltaics. They are made of an A + cation, ...
- MIT Researchers Make Discovery in Solar Cell Technology for Next-Gen Sustainable Energy Solutionson March 1, 2024 at 12:09 am
This study heralds a new era of sustainable energy options, presenting lightweight and affordable solar panels suitable for integration into diverse surfaces, ranging from paper to flexible plastics.
- Guiding future research on 'extraordinary potential' of next-generation solar cellson February 29, 2024 at 2:03 pm
Today's commercial solar panels can convert about 15% to 20% of the sunlight they absorb into electrical energy—but they could be much more efficient, according to researchers at Soochow University.
- Researchers improve the stability of perovskite solar cellson February 29, 2024 at 1:42 pm
Perovskite solar cells are thought of as the strongest contender to replace conventional silicon solar cells in next-generation photovoltaics. They are made of an A+ cation, a B2+ divalent cation, and ...
- MIT-Led Study Enhances Perovskite Solar Cell Efficiencyon February 29, 2024 at 11:35 am
Research unveils nanoscale engineering strategies to boost efficiency and durability of next-gen solar technology ...
- The Future of Energy – Scientists Unveil Roadmap for Bringing Perovskite/Silicon Tandem Solar Cells to Marketon February 29, 2024 at 4:08 am
Researchers at King Abdullah University of Science and Technology (KAUST) have developed a comprehensive plan to introduce perovskite/silicon tandem solar cells into the marketplace, setting the stage ...
- Why Researchers Are Excited About Perovskite Solar Cellson February 28, 2024 at 11:53 pm
Researchers out of MIT have published a “guidebook” for controlling and engineering perovskite solar cells. These cells could “redefine the solar energy landscape,” wrote Michelle Lewis at Electrek, ...
- MIT just released directions for commercializing perovskite solar cellson February 28, 2024 at 1:34 pm
An MIT-led team revealed a "guidebook" for how to tune surface properties of perovskites, a silicon alternative – why that's huge for solar.
- Reducing halide segregation in wide-bandgap mixed-halide perovskite solar cells using redox mediatorson February 28, 2024 at 3:50 am
Multi-junction solar cells, solar cells comprised of many individual semiconductor junctions stacked together, have the potential of outperforming single-junction solar cells both in terms of ...
via Bing News