Columbia Engineers Confirm Graphene as Strongest Material (Jul 18, 2008)
NEW YORK, July 18, 2008 — Research scientists at Columbia University’s Fu Foundation School of Engineering and Applied Science have completed the first strength tests on the carbon material graphene proving it to be the strongest material ever measured. Graphene holds great promise for the development of nano-scale devices and equipment. It consists of a single layer of graphite atoms arranged in a hexagonal lattice, similar to a honeycomb. As a two-dimensional material, every atom is exposed to the surface. It forms the basis of graphite fibers used in tennis racquets and other durable products. When rolled, very useful tiny tubes called nanotubes can be fabricated. The studies were conducted by postdoctoral researcher Changgu Lee and graduate student Xiaoding Wei, in the research groups of mechanical engineering professors James Hone and Jeffrey Kysar. The findings are published today in the new edition of Science: http://www.sciencemag.org/cgi/content/full/321/5887/385 “Our research establishes graphene as the strongest material ever measured, some 200 times stronger than structural steel,” Hone said. “It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran-Wrap.” Until now, graphene’s estimated strength, elasticity and breaking point were based on complex computer modeling theories. Laboratory tests had been stymied because of two major experimental challenges: the complexity in mechanically grasping graphene specimens to measure their elongation under force and the difficulty of making specimens small enough to be free of imperfections. “Our team sidestepped the size issue by creating samples small enough to be defect-free,” said Kysar. The team culled microscopic graphene samples, ones specimens where every single atom is on the surface, from larger graphite crystals. These newly created, two-dimensional samples were then placed over small circular holes etched in silicon to create miniature circular films only one atom thick. The graphene adhered to the silicon because of the attraction between their atoms, solving the second challenge. The scientists tested the strength of the films by pushing on their centers with a diamond-tipped atomic force microscope with a radius of 20 billionths of a meter. The absence of flaws in the samples, each about one micron in diameter or one percent of the width of a human hair, enabled the scientists to test both elasticity and breaking point properties. The scientists collected more than 67 test values on 23 separate films. “Until now, there’s been no definitive set of experiments that people can use to validate or invalidate the computer simulations that model the mechanical properties of materials at strains literally up to the breaking point, ” said Kysar. “It’s important because this is a fundamental parameter for all types of materials. “The Air Force wants to introduce new materials within a five-year cycle, versus 20 years now, so being able to predict the mechanical behavior of how a new material will fail under the most extreme circumstances will make it much less expensive and less time consuming to develop, and with better materials for everyday life.” “Though the strength of any practical material is still limited by many types of defects, the research can lead to a better understanding of the behavior of materials at extreme conditions, such as exist near the tip of a crack,” said Hone. “This can in turn lead to far more robust materials, ones more resistant to oxidation and fatigue. Achieving a better understanding of how materials fail allows us to design and create newer, safer materials, and ultimately to build a safer, more efficient environment for us.” To learn more about Columbia’s Department of Mechanical Engineering, visit: http://www.engineering.columbia.edu/bulletin/departments_academic_programs/me/index.html

Columbia Engineers Confirm Graphene as Strongest Material (Jul 18, 2008)
NEW YORK, July 18, 2008 — Research scientists at Columbia University’s Fu Foundation School of Engineering and Applied Science have completed the first strength tests on the carbon material graphene proving it to be the strongest material ever measured. Graphene holds great promise for the development of nano-scale devices and equipment. It consists of a single layer of graphite atoms arranged in a hexagonal lattice, similar to a honeycomb. As a two-dimensional material, every atom is exposed to the surface. It forms the basis of graphite fibers used in tennis racquets and other durable products. When rolled, very useful tiny tubes called nanotubes can be fabricated. The studies were conducted by postdoctoral researcher Changgu Lee and graduate student Xiaoding Wei, in the research groups of mechanical engineering professors James Hone and Jeffrey Kysar. The findings are published today in the new edition of Science: http://www.sciencemag.org/cgi/content/full/321/5887/385 “Our research establishes graphene as the strongest material ever measured, some 200 times stronger than structural steel,” Hone said. “It would take an elephant, balanced on a pencil, to break through a sheet of graphene the thickness of Saran-Wrap.” Until now, graphene’s estimated strength, elasticity and breaking point were based on complex computer modeling theories. Laboratory tests had been stymied because of two major experimental challenges: the complexity in mechanically grasping graphene specimens to measure their elongation under force and the difficulty of making specimens small enough to be free of imperfections. “Our team sidestepped the size issue by creating samples small enough to be defect-free,” said Kysar. The team culled microscopic graphene samples, ones specimens where every single atom is on the surface, from larger graphite crystals. These newly created, two-dimensional samples were then placed over small circular holes etched in silicon to create miniature circular films only one atom thick. The graphene adhered to the silicon because of the attraction between their atoms, solving the second challenge. The scientists tested the strength of the films by pushing on their centers with a diamond-tipped atomic force microscope with a radius of 20 billionths of a meter. The absence of flaws in the samples, each about one micron in diameter or one percent of the width of a human hair, enabled the scientists to test both elasticity and breaking point properties. The scientists collected more than 67 test values on 23 separate films. “Until now, there’s been no definitive set of experiments that people can use to validate or invalidate the computer simulations that model the mechanical properties of materials at strains literally up to the breaking point, ” said Kysar. “It’s important because this is a fundamental parameter for all types of materials. “The Air Force wants to introduce new materials within a five-year cycle, versus 20 years now, so being able to predict the mechanical behavior of how a new material will fail under the most extreme circumstances will make it much less expensive and less time consuming to develop, and with better materials for everyday life.” “Though the strength of any practical material is still limited by many types of defects, the research can lead to a better understanding of the behavior of materials at extreme conditions, such as exist near the tip of a crack,” said Hone. “This can in turn lead to far more robust materials, ones more resistant to oxidation and fatigue. Achieving a better understanding of how materials fail allows us to design and create newer, safer materials, and ultimately to build a safer, more efficient environment for us.” To learn more about Columbia’s Department of Mechanical Engineering, visit: http://www.engineering.columbia.edu/bulletin/departments_academic_programs/me/index.html

Louis Brus recepient of Kavli Prize (May 28, 2008)
The 2008 Kavli Prize for Nanoscience was shared by Louis Brus of Columbia Univeristy and Sumio Iijima of Meijo University in Nagoya, Japan. Professor Brus is a pioneer in the study of particles called quantum dots, which scientists are now investigating for such uses as early identification of cancer and improved computer displays.

Limin Huang and Zhang Jia receive MRS Poster Prize (Nov 26, 2007)
We are pround to announce that Limin Huang and Zhang Jia of the Stephen OBrien group were poster award winners during the Fall 2007 MRS Conference on November 26, 2007. Their poster is entitled, Alcohol CVD Synthesis of Flow-Aligned SWCNTs.

Clean Room Supervisor Position Available (Nov 19, 2007)
Announcement: Clean Room Position.
Columbia University Senior Staff Associate - Clean Room Supervisor
Columbia University is seeking an experienced Clean Room Supervisor to provide overall operating supervision, administration, and leadership for its research Clean Room Operations. Reporting to the Director of Center for Integrated Science and Engineering, the Clean Room Supervisor is responsible to Columbia University Clean Room Committee. The incumbent creates and maintains safe and effective clean room operations within Columbia University?s CEPSR Clean Room, assures adherence and compliance with all University and government requirements and regulations. The incumbent supervises Clean Room technical staff and assures proper maintenance of Clean Room equipment including preventative and routine maintenance, manages the financial operations of the Clean Room in accordance with University policies and the directives of the Clean Room Committee, works with Columbia University faculty and research staff to identify new equipment and facility needs, and takes leadership in developing proposals and working with other University resources. The incumbent also organizes and supervises training program for clean room users, manages Clean Room supplies, maintains professional records for all major equipment, prepares and maintains written SOP (standard operating procedures) for all major clean room equipment items, and serves as an internal consultant for the design of various demonstration devices. Requirements: Bachelor?s degree in electrical engineering, physics, Materials Science required. PhD preferred. A minimum of 8 years of operational experience in semiconductor fabrication facility or related experience. Strong technical experience in conventional clean operations and electronic and mechanical device fabrication, in maintenance of semiconductor processing tools and/or metrology tools, and in the design of recipe driven processes. Understanding for new and modern laboratory-scale fabrication equipment and processes such as electron beam lithography and nanoimprint fabrication. Ability to work with wide variety of Clean Room users, to develop processes using standard metrology tools, and to work with frequent interruptions with minimal supervision. Strong management, leadership, and communication skills. Excellent interpersonal, analytical reasoning, problem solving, and organization skills. Must be able to exercise mature judgment and initiative. Please e-mail resume to James Yardley, Director of Center for Integrated Science and Engineering, Columbia University at jy307@columbia.edu. Application must be received by December 31, 2007. Columbia University is an equal opportunity/Affirmative Action employer. Minorities and women are encouraged to apply.

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