Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > 2-D material a brittle surprise: Rice University researchers finds molybdenum diselenide not as strong as they thought

A sequence shows a molybdenum diselenide sample mounted on a nanomechanical measuring device at Rice University, where scientists determine the material is far more brittle than they expected. The atom-thick material is progressively stretched in the photos, clockwise from top left, until it completely splits. The researchers suspect defects as small as a single atom are the starting point for the brittle behavior.Credit: Lou Group/Rice University
A sequence shows a molybdenum diselenide sample mounted on a nanomechanical measuring device at Rice University, where scientists determine the material is far more brittle than they expected. The atom-thick material is progressively stretched in the photos, clockwise from top left, until it completely splits. The researchers suspect defects as small as a single atom are the starting point for the brittle behavior.

Credit: Lou Group/Rice University

Abstract:
Scientists at Rice University have discovered that an atom-thick material being eyed for flexible electronics and next-generation optical devices is more brittle than they expected.

2-D material a brittle surprise: Rice University researchers finds molybdenum diselenide not as strong as they thought

Houston, TX | Posted on November 14th, 2016

The Rice team led by materials scientist Jun Lou tested the tensile strength of two-dimensional, semiconducting molybdenum diselenide and discovered that flaws as small as one missing atom can initiate catastrophic cracking under strain.

The team's report appears this month in Advanced Materials.

The finding may cause industry to look more carefully at the properties of 2-D materials before incorporating them in new technologies, he said.

"It turns out not all 2-D crystals are equal," said Lou, a Rice professor of materials science and nanoengineering. "Graphene is a lot more robust compared with some of the others we're dealing with right now, like this molybdenum diselenide. We think it has something to do with defects inherent to these materials."

The defects could be as small as a single atom that leaves a vacancy in the crystalline structure, he said. "It's very hard to detect them," he said. "Even if a cluster of vacancies makes a bigger hole, it's difficult to find using any technique. It might be possible to see them with a transmission electron microscope, but that would be so labor-intensive that it wouldn't be useful."

Molybdenum diselenide is a dichalcogenide, a two-dimensional semiconducting material that appears as a graphene-like hexagonal array from above but is actually a sandwich of metallic atoms between two layers of chalcogen atoms, in this case, selenium. Molybdenum diselenide is being considered for use as transistors and in next-generation solar cells, photodetectors and catalysts as well as electronic and optical devices.

Lou and colleagues measured the material's elastic modulus, the amount of stretching a material can handle and still return to its initial state, at 177.2 (plus or minus 9.3) gigapascals. Graphene is more than five times as elastic. They attributed the large variation to pre-existing flaws of between 3.6 and 77.5 nanometers.

Its fracture strength, the amount of stretching a material can handle before breaking, was measured at 4.8 (plus or minus 2.9) gigapascals. Graphene is nearly 25 times stronger.

Part of the project led by Rice postdoctoral researcher Yingchao Yang required moving molybdenum diselenide from a growth chamber in a chemical vapor deposition furnace to a microscope without introducing more defects. Yang solved the problem using a dry transfer process in place of a standard acid washing that would have ruined the samples.

To test samples, Yang placed rectangles of molybdenum diselenide onto a sensitive electron microscope platform invented by the Lou group. Natural van der Waals forces held the samples in place on springy cantilever arms that measured the applied stress.

Lou said the group attempted to measure the material's fracture toughness, an indicator of how likely cracks are to propagate, as they had in an earlier study on graphene. But they found that pre-cutting cracks into molybdenum diselenide resulted in it shattering before stress could be applied, he said.

"The important message of this work is the brittle nature of these materials," Lou said. "A lot of people are thinking about using 2-D crystals because they're inherently thin. They're thinking about flexible electronics because they are semiconductors and their theoretical elastic strength should be very high. According to our calculations, they can be stretched up to 10 percent.

"But in reality, because of the inherent defects, you rarely can achieve that much strength. The samples we have tested so far broke at 2 to 3 percent (of the theoretical maximum) at most," Lou said. "That should still be fine for most flexible applications, but unless they find a way to quench the defects, it will be very hard to achieve the theoretical limits."

Co-authors of the paper are Rice graduate students Emily Hacopian, Weibing Chen, Jing Zhang and Bo Li, alumna Yongji Gong and Pulickel Ajayan, chair of Rice’s Department of Materials Science and NanoEngineering, the Benjamin M. and Mary Greenwood Anderson Professor in Engineering and a professor of chemistry; Xing Li of Rice and Peking University, China; Minru Wen of Tsinghua University, China, and the Georgia Institute of Technology; Wu Zhou of Oak Ridge National Laboratory, Oak Ridge, Tenn.; Qing Chen of Peking University; and Ting Zhu of the Georgia Institute of Technology.

The research was supported by the Air Force Office of Scientific Research, the Welch Foundation, the Department of Energy Office of Basic Energy Sciences, the National Science Foundation and the National Science Foundation of China.

####

About Rice University
Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,910 undergraduates and 2,809 graduate students, Rice’s undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for happiest students and for lots of race/class interaction by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance. To read “What they’re saying about Rice,” go to http://tinyurl.com/RiceUniversityoverview .

Follow Rice News and Media Relations via Twitter @RiceUNews

For more information, please click here

Contacts:
David Ruth
713-348-6327


Mike Williams
713-348-6728

Copyright © Rice University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related Links

Read the abstract at:

Lou Group:

Department of Materials Science and NanoEngineering:

George R. Brown School of Engineering:

Related News Press

News and information

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Tumor microenvironment dynamics: the regulatory influence of long non-coding RNAs April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Next-generation drug delivery innovation! DGIST develops precision therapeutics using exosomes April 25th, 2025

SMART researchers pioneer first-of-its-kind nanosensor for real-time iron detection in plants February 28th, 2025

Flexible Electronics

Development of 'transparent stretchable substrate' without image distortion could revolutionize next-generation displays Overcoming: Poisson's ratio enables fully transparent, distortion-free, non-deformable display substrates February 28th, 2025

Flexible electronics integrated with paper-thin structure for use in space January 17th, 2025

Beyond wires: Bubble technology powers next-generation electronics:New laser-based bubble printing technique creates ultra-flexible liquid metal circuits November 8th, 2024

2 Dimensional Materials

Closing the gaps — MXene-coating filters can enhance performance and reusability February 28th, 2025

New 2D multifractal tools delve into Pollock's expressionism January 17th, 2025

Graphene/ Graphite

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

Breakthrough in proton barrier films using pore-free graphene oxide: Kumamoto University researchers achieve new milestone in advanced coating technologies September 13th, 2024

A 2D device for quantum cooling:EPFL engineers have created a device that can efficiently convert heat into electrical voltage at temperatures lower than that of outer space. The innovation could help overcome a significant obstacle to the advancement of quantum computing technol July 5th, 2024

Videos/Movies

New X-ray imaging technique to study the transient phases of quantum materials December 29th, 2022

Solvent study solves solar cell durability puzzle: Rice-led project could make perovskite cells ready for prime time September 23rd, 2022

Scientists prepare for the world’s smallest race: Nanocar Race II March 18th, 2022

Visualizing the invisible: New fluorescent DNA label reveals nanoscopic cancer features March 4th, 2022

Govt.-Legislation/Regulation/Funding/Policy

Rice researchers harness gravity to create low-cost device for rapid cell analysis February 28th, 2025

Department of Energy announces $71 million for research on quantum information science enabled discoveries in high energy physics: Projects combine theory and experiment to open new windows on the universe January 17th, 2025

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

Chainmail-like material could be the future of armor: First 2D mechanically interlocked polymer exhibits exceptional flexibility and strength January 17th, 2025

Possible Futures

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Tumor microenvironment dynamics: the regulatory influence of long non-coding RNAs April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Next-generation drug delivery innovation! DGIST develops precision therapeutics using exosomes April 25th, 2025

Chip Technology

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Development of 'transparent stretchable substrate' without image distortion could revolutionize next-generation displays Overcoming: Poisson's ratio enables fully transparent, distortion-free, non-deformable display substrates February 28th, 2025

New ocelot chip makes strides in quantum computing: Based on "cat qubits," the technology provides a new way to reduce quantum errors February 28th, 2025

Optical computing/Photonic computing

Groundbreaking research unveils unified theory for optical singularities in photonic microstructures December 13th, 2024

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

New material to make next generation of electronics faster and more efficient With the increase of new technology and artificial intelligence, the demand for efficient and powerful semiconductors continues to grow November 8th, 2024

Groundbreaking precision in single-molecule optoelectronics August 16th, 2024

Nanoelectronics

Interdisciplinary: Rice team tackles the future of semiconductors Multiferroics could be the key to ultralow-energy computing October 6th, 2023

Key element for a scalable quantum computer: Physicists from Forschungszentrum Jülich and RWTH Aachen University demonstrate electron transport on a quantum chip September 23rd, 2022

Reduced power consumption in semiconductor devices September 23rd, 2022

Atomic level deposition to extend Moore’s law and beyond July 15th, 2022

Discoveries

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Tumor microenvironment dynamics: the regulatory influence of long non-coding RNAs April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Next-generation drug delivery innovation! DGIST develops precision therapeutics using exosomes April 25th, 2025

Materials/Metamaterials/Magnetoresistance

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Chainmail-like material could be the future of armor: First 2D mechanically interlocked polymer exhibits exceptional flexibility and strength January 17th, 2025

Enhancing transverse thermoelectric conversion performance in magnetic materials with tilted structural design: A new approach to developing practical thermoelectric technologies December 13th, 2024

FSU researchers develop new methods to generate and improve magnetism of 2D materials December 13th, 2024

Announcements

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Tumor microenvironment dynamics: the regulatory influence of long non-coding RNAs April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Next-generation drug delivery innovation! DGIST develops precision therapeutics using exosomes April 25th, 2025

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers/Posters

Enhancing power factor of p- and n-type single-walled carbon nanotubes April 25th, 2025

Tumor microenvironment dynamics: the regulatory influence of long non-coding RNAs April 25th, 2025

Ultrafast plasmon-enhanced magnetic bit switching at the nanoscale April 25th, 2025

Next-generation drug delivery innovation! DGIST develops precision therapeutics using exosomes April 25th, 2025

Military

Quantum engineers ‘squeeze’ laser frequency combs to make more sensitive gas sensors January 17th, 2025

Chainmail-like material could be the future of armor: First 2D mechanically interlocked polymer exhibits exceptional flexibility and strength January 17th, 2025

Single atoms show their true color July 5th, 2024

NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024

Grants/Sponsored Research/Awards/Scholarships/Gifts/Contests/Honors/Records

Researchers uncover strong light-matter interactions in quantum spin liquids: Groundbreaking experiment supported by Rice researcher reveals new insights into a mysterious phase of quantum matter December 13th, 2024

New discovery aims to improve the design of microelectronic devices September 13th, 2024

Physicists unlock the secret of elusive quantum negative entanglement entropy using simple classical hardware August 16th, 2024

Atomic force microscopy in 3D July 5th, 2024

Photonics/Optics/Lasers

Bringing the power of tabletop precision lasers for quantum science to the chip scale December 13th, 2024

Researchers succeed in controlling quantum states in a new energy range December 13th, 2024

Groundbreaking research unveils unified theory for optical singularities in photonic microstructures December 13th, 2024

UCF researcher discovers new technique for infrared “color” detection and imaging: The new specialized tunable detection and imaging technique for infrared photons surpasses present technology and may be a cost-effective method of capturing thermal imaging or night vision, medica December 13th, 2024

Research partnerships

SMART researchers pioneer first-of-its-kind nanosensor for real-time iron detection in plants February 28th, 2025

Gene therapy relieves back pain, repairs damaged disc in mice: Study suggests nanocarriers loaded with DNA could replace opioids May 17th, 2024

Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024

Researchers’ approach may protect quantum computers from attacks March 8th, 2024

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project