. | . |
On-surface chemistry leads to novel products by Staff Writers Basel, Switzerland (SPX) Sep 15, 2016
On-surface chemical reactions can lead to novel chemical compounds not yet synthesized by solution chemistry. The first-step, second-step, and third-step products can be analyzed in detail using a high-resolution atomic force microscope, as demonstrated in Nature Communications by scientists from the Swiss Nanoscience Institute and the Department of Physics at Basel University and their colleagues from Japan and Finland. In numerous nanotechnology applications, individual molecules are placed on surfaces to fulfill specific functions - such as conducting an electrical current or emitting a light signal. Ideally, scientists will synthetize these sometimes extremely complex chemical compounds directly on the surface. The on-surface chemical reactions can be followed step by step with the aid of ultra-high-resolution atomic force microscopes. The data obtained also enables them to calculate the precise molecular structure and the energetics along the path. For their experiments, colleagues of Professor Ernst Meyer from the University of Basel selected a molecule consisting of three benzene rings joined by a triple bond. When the researchers apply this molecule to a silver surface, the molecules arrange themselves in a consistent pattern - but there is no chemical reaction.
Copper as a catalyst When the sample is heated to 200 C, a further reaction step takes place in which two pentagonal rings are formed. A further increase in temperature to 400 C causes a cleaving of hydrogen atoms and forms a further carbon-carbon bond. The final two reaction steps lead to aromatic hydrocarbon compounds, which had previously not been synthetized in solution chemistry. The researchers conducted these experiments in ultra-high vacuum conditions and were able to monitor the synthesis using a high-resolution atomic force microscope with a carbon monoxide terminated tip. Comparative computer calculations generated the precise molecular structure, which perfectly matched the microscope images.
Tailored nanostructures "This extremely pure form of chemistry provides us with tailored on-surface nanostructures that can be used in a variety of ways," says Meyer, commenting on the work largely performed by Dr. Shigeki Kawai. In the example presented, the copper surface functions as a catalyst; the chemical reaction of the precursor molecules is controlled by adding heat and can be monitored via atomic force microscopy.
Related Links University of Basel Space Technology News - Applications and Research
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |