Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Growing strained crystals could improve performance of perovskite electronics

10.01.2020

A new method could enable researchers to fabricate more efficient and longer lasting perovskite solar cells, LEDs and photodetectors.

By growing thin perovskite films on substrates with different compositions, engineers at the University of California San Diego have invented a way of fabricating perovskite single crystals with precisely deformed, or strained, structures.


Strain-engineered, single crystal thin film of perovskite grown on a series of substrates with varying compositions and lattice sizes.

Credit: David Baillot/UC San Diego Jacobs School of Engineering

The work was published Jan. 8 in Nature.

Engineering a small amount of strain in perovskites is of great interest because it provides a way to make significant changes in the material's properties, such as how it conducts electricity, absorbs and transmits light, or how stable it is.

"You can use strain engineering as a knob to tune existing functions or even install new functions in a material," said Sheng Xu, a professor of nanoengineering at the UC San Diego Jacobs School of Engineering and the senior author of the study.

There are techniques that use heat to introduce strain in perovskite crystals, but that strain is typically short lived or uncontrollable in terms of its magnitude, which makes these strain-engineered perovskites impractical to use. Existing strain engineering techniques are also incompatible with device fabrication processes.

Xu and his team tackled these problems by carefully growing deformed perovskite single crystals. Their technique permanently embeds strain into the material's structure and allows them to tailor the amount of strain--the more deformed the crystal lattice, the higher the strain.

The type of perovskite investigated in this study is alpha-formamidinium lead iodide, which has been used to create the highest efficiency perovskite solar cells to date. The researchers grew crystals of the material on a series of perovskite substrates with varying compositions and lattice sizes--a process called heteroepitaxial growth.

As the material crystallized, it adopted the lattice size of its substrate, which essentially forced the alpha-formamidinium lead iodide crystals to grow differently than they normally do.

"Thus, the lattices in the material are deformed and strained to different degrees, depending on the lattice mismatch between material and substrate," explained Yimu Chen, a nanoengineering Ph.D. student in Xu's lab and co-first author of the study.

"Because we are introducing strain at the atomic level, we can precisely design the strain and control it," said Yusheng Lei, who is also a nanoengineering Ph.D. student in Xu's lab and the other co-first author of the study.

The researchers grew perovskite crystals with five different levels of strain ranging from 0 to -2.4%. They found that -1.2% strain produced samples with the best charge-carrier mobility.

The team also reported another interesting discovery: growing alpha-formamidinium lead iodide crystals with strain stabilized its photoactive alpha phase.

"In its strain-free form, alpha-formamidinium lead iodide undergoes a phase transition from a photoactive phase to a non-photoactive phase, which is bad for photovoltaic applications," Chen said. "With our growth method, we can lock the material's crystal structure with that of the substrate to prevent this phase transition and enhance its phase stability."

In future studies, the researchers will explore what new properties and functionalities they can strain engineer into perovskites using their method. They will also work on scaling up their process to grow large, single-crystalline thin films for industrial applications.

###

Paper title: "Strain engineering and epitaxial stabilization of halide perovskites." Co-authors include Yuheng Li, Yugang Yu, Jinze Cai, Yue Gu, Chunfeng Wang, Woojin Choi, Hongjie Hu, Chonghe Wang, Yang Li, Jiawei Song, Jingxin Zhang, Baiyan Qi, Muyang Lin, Zuorui Zhang, Shadi Dayeh, Kesong Yang and Yu-Hwa Lo, UC San Diego; Ming-Hui Chiu and Lain-Jong Li, King Abdullah University of Science and Technology, Kingdom of Saudi Arabia; and Rahul Rao, Ahmad E. Islam and Benji Maruyama, Air Force Research Laboratory, Wright Patterson Air Force Base.

This work was supported by UC San Diego startup funds. This work was performed in part at the San Diego Nanotechnology Infrastructure (SDNI) at UC San Diego, a member of the National Nanotechnology Coordinated Infrastructure, which is supported by the National Science Foundation (grant ECCS-1542148).

Media Contact

Liezel Labios
llabios@ucsd.edu
858-246-1124

 @UCSanDiego

http://www.ucsd.edu 

Liezel Labios | EurekAlert!
Further information:
http://dx.doi.org/10.1038/s41586-019-1868-x

More articles from Power and Electrical Engineering:

nachricht Skoltech scientists get a sneak peek of a key process in battery 'life'
28.05.2020 | Skolkovo Institute of Science and Technology (Skoltech)

nachricht Electric pulses precisely shape 3D-printed metal parts
28.05.2020 | Universität des Saarlandes

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

Im Focus: New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.

researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

German-British Research project for even more climate protection in the rail industry

28.05.2020 | Transportation and Logistics

A special elemental magic

28.05.2020 | Physics and Astronomy

Skoltech scientists get a sneak peek of a key process in battery 'life'

28.05.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>