Driving Innovation: Direct Imaging vs. Conventional Exposure
It’s Only Common Sense: Selling to Today's Generation of Buyers
Dan’s Biz Bookshelf: ‘Believe in Better'
Rendering a 2D Perovskite Template into a 3D Film
March 22, 2019 | University of GroningenEstimated reading time: 2 minutes
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.
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).
Image Caption: The 2D films based on 2-phenylethylammonium lead iodide produce 3D formamidinium lead iodide films via cation exchange.
Industrial Production
'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.
Blade
'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.'
Share on:
Suggested Items
It’s Only Common Sense: Why Sales Teams Fail (and How to Fix Them)
06/22/2025 | Dan Beaulieu -- Column: It's Only Common SenseIn sales, success is never a given. Despite best intentions, the most well-resourced sales teams can stumble. Understanding why is the first step toward creating a high-performing sales force. Here are the main reasons sales teams fail—and actionable strategies to fix them.
STI Celebrates Travis Wease’s 10 Years of Dedicated Service
06/17/2025 | STI Electronics, Inc.STI Electronics, Inc., a full-service organization providing training services, training materials, analytical/failure analysis, prototyping, and contract electronic manufacturing, proudly celebrated the 10-year work anniversary of Travis Wease, Master Instructor and valued team member.
The Marketing Minute: A Brand Visibility Playbook—Get Seen, Heard, and Remembered
06/18/2025 | Brittany Martin -- Column: The Marketing MinuteIn the competitive world of electronics, recognition isn’t given—it’s earned. With so many companies vying for attention, how do you ensure your brand voice stands out and stays top-of-mind? This month, I’m focusing on building recognition using three high-impact tools: social media, paid advertising, and thought leadership.
The Government Circuit: From Tax Policy to Tariffs, Denver to Delhi, Speaking Up for Electronics
06/18/2025 | Chris Mitchell -- Column: The Government CircuitI had the privilege of attending the June 3 opening ceremony of AT&S’s HTB3 facility in Leoben, Austria—a milestone moment for Europe’s electronics ecosystem. HTB3 is now the first and only facility in Europe capable of both developing and producing high-performance IC substrates—the advanced platforms that allow powerful chips to connect, process, and function. As demand for AI, 5G, and other cutting-edge technologies grows, so too does the need for sophisticated substrates like those HTB3 will produce.
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
06/13/2025 | Marcy LaRont, I-Connect007Today is Friday the 13th, and in much of Western folklore, this is a day when bad luck is lurking. But while Friday the 13th may top Western superstition charts, the global calendar is sprinkled with its own unlucky legends. In Spain and Greece, the bad juju lands on Tuesday the 13th—a day linked to Mars, the god of war, and naturally, chaos. In Italy, it’s Friday the 17th that is feared, thanks to the Roman numeral XVII, which can be rearranged to spell VIXI—Latin for “I have lived” (a poetic way of saying you’re dead).