Scientists Create New Class of Two-Dimensional Materials
June 10, 2019 | University of California, IrvineEstimated reading time: 2 minutes
In a paper published this week in Nature, materials science researchers at the University of California, Irvine and other institutions unveil a new process for producing oxide perovskite crystals in exquisitely flexible, free-standing layers.
Image Caption: “Through our successful fabrication of ultrathin perovskite oxides down to the monolayer limit, we’ve created a new class of two-dimensional materials,” says Xiaoqing Pan, professor of materials science & engineering and Henry Samueli Endowed Chair in Engineering at UCI. “Since these crystals have strongly correlated effects, we anticipate they will exhibit qualities similar to graphene that will be foundational to next-generation energy and information technologies.” Xiaoqing Pan / UCI
A two-dimensional rendition of this substance is intriguing to scientists and engineers, because 2D materials have been shown to possess remarkable electronic properties, including high-temperature superconductivity. Such compounds are prized as potential building blocks in multifunctional high-tech devices for energy and quantum computing, among other applications.
“Through our successful fabrication of ultrathin perovskite oxides down to the monolayer limit, we’ve created a new class of two-dimensional materials,” said co-author Xiaoqing Pan, professor of materials science & engineering and Henry Samueli Endowed Chair in Engineering at UCI. “Since these crystals have strongly correlated effects, we anticipate they will exhibit qualities similar to graphene that will be foundational to next-generation energy and information technologies.”
For all of their promising physical and chemical properties, oxide perovskites are difficult to render in flat layers due to the clunky, strongly bonded structure of their crystals. Earlier efforts at making free-standing, monolayer films of the material through the pulsed laser deposition method failed.
Pan’s cross-disciplinary group of researchers applied a technique called molecular beam epitaxy to grow the thin oxide films layer by layer on a template with a water-dissolvable buffer, followed by etching and transfer.
“Most of the known two-dimensional materials can be synthesized by exfoliation or by chemical deposition, as their bulk crystals consist of unique layered structures in which many strong covalently bonded planes are held together by weak van der Waals interactions,” he said. “But oxide perovskite is different; like most oxide materials, it has strong chemical bonds in three dimensions, making it especially challenging to fabricate into two dimensions.”
Pan, who holds a dual appointment as a professor of physics & astronomy and directs the Irvine Materials Research Institute, said that molecular beam epitaxy is a more precise method for growing oxide perovskite thin films with almost no defects. He knows this because his research team was able to review its work at atomic resolution using aberration-corrected transmission electron microscopy.
“TEM played a crucial role in this project, because it provided important feedback for the optimization of film growth conditions and allowed us to directly observe novel phenomena, including the crystal symmetry breaking and unexpected polarization enhancement under the reduced dimension,” Pan said.
“Given the outstanding physical and chemical properties of oxide perovskites and novel phenomena emergent at the monolayer limit, this work opens new possibilities in the exploration of quantum behaviors in strongly correlated two-dimensional materials,” he added.
Pan and his team at UCI were joined by collaborators at China’s Nanjing University and the University of Nebraska. They used TEM facilities at UCI’s Irvine Materials Research Institute. The project was supported by the U.S. Department of Energy Office of Basic Energy Sciences’ materials sciences and engineering division, under grant DE-SC0014430.
Suggested Items
Indium Corporation, Industry Partners to Showcase Products “Live@APEX”
03/26/2024 | Indium CorporationIndium Corporation®, in cooperation with its industry partners, will feature its proven solder solutions live on the show floor throughout IPC APEX Expo from Apr. 9‒11 in Anaheim, Calif., U.S.
Dymax Will Exhibit Light-Cure Solutions for Today’s Electronics at IPC APEX 2024
03/26/2024 | DymaxDymax, a leading manufacturer of rapid and light-curing materials and equipment, will exhibit at the IPC APEX EXPO 2024 in Anaheim, CA, April 9-11.
Ventec to Launch New Bondply Dielectrics and Value-Added Services at IPC APEX EXPO 2024
03/26/2024 | Ventec International GroupVentec International Group is to reveal new products for advanced signal integrity and thermal performance, and introduce services, during IPC APEX EXPO 2024, April 9-11 on booth # 4309.
Electra Polymers Ltd Expands Manufacturing Capacity, Invests in New Facilities and Talent
03/26/2024 | Electra Polymers LtdElectra Polymers Ltd, a leading provider of coatings for the electronics industry, proudly announces a significant expansion of its manufacturing capacity for inkjet materials. The company is making substantial investments in new facilities, talent acquisition, and cutting-edge laboratory equipment to meet the increasing demand for high-performance functional inkjet materials in the market.
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
03/22/2024 | Nolan Johnson, I-Connect007This week's news feed contains a bunch of big money items, as well as some interesting industrial and technology puzzles to be solved. There’s even some down-home people news from the Dallas SMTA conference held this week. Don’t overlook the latest issue of PCB007 Magazine, either. The topic is sustainability, which is becoming an ecosystem of its own.