Navigation Links
Engineers fine-tune the sensitivity of nano-chemical sensor
Date:5/8/2013

Researchers have discovered a technique for controlling the sensitivity of graphene chemical sensors.

The sensors, made of an insulating base coated with a graphene sheet--a single-atom-thick layer of carbon--are already so sensitive that they can detect an individual molecule of gas. But manipulating the chemical properties of the insulating layer, without altering the graphene layer, may yet improve their ability to detect the most minute concentrations of various gases.

The finding "will open up entirely new possibilities for modulation and control of the chemical sensitivity of these sensors, without compromising the intrinsic electrical and structural properties of graphene," says Amin Salehi-Khojin, assistant professor of mechanical and industrial engineering at the University of Illinois at Chicago, and principal investigator on the study. He and his coworkers at the UIC College of Engineering collaborated with researchers from the Beckman Institute and the Micro and Nanotechnology Laboratory at the University of Illinois at Urbana-Champaign and two institutions in Korea. Their findings are reported in the journal Nano Letter, available online in advance of publication.

Since its discovery nearly 10 years ago, graphene--in sheets, or rolled into nanotubes--has attracted huge scientific interest. Composed of a single layer of carbon atoms, graphene has potential for use in hundreds of high-tech applications. Its 2-D structure, exposing its entire volume, makes it attractive as a highly sensitive gas detector.

Salehi-Khojin's team, and others, earlier found that graphene chemical sensors depended on a structural flaw around a carbon atom for their sensitivity. They set out to show that "pristine" graphene sensors--made of graphene that was perfectly flawlesswouldn't work. But when they tested these sensors, they found they were still sensitive to trace gas molecules.

"This was a very surprising result," Salehi-Khojin said.

The researchers tested the sensor layer by layer. They found that pristine graphene is insensitive, as they had predicted.

They next set about removing any flaws, or reactive sites called dangling bonds, from the insulating layer. When a pristine insulating layer was tested with pristine graphene, again there was no sensitivity.

"But when dangling bonds were added back onto the insulating layer, we observed a response," said Bijandra Kumar, a post-doctoral research associate at UIC and first author of the Nano Letter study.

"We could now say that graphene itself is insensitive unless it has defects--internal defects on the graphene surface, or external defects on the substrate surface," said UIC graduate student Poya Yasaei.

The finding opens up a new "design space," Salehi-Khojin said. Controlling external defects in the supporting substrates will allow graphene chemFETs to be engineered that may be useful in a wide variety of applications.


'/>"/>

Contact: Jeanne Galatzer-Levy
jgala@uic.edu
312-996-1583
University of Illinois at Chicago
Source:Eurekalert

Related biology technology :

1. Stanford engineers use nanophotonics to reshape on-chip computer data transmission
2. Arizona State University engineers aim to improve performance of technology in extreme environments
3. Stanford engineers weld nanowires with light
4. Straintronics: Engineers create piezoelectric graphene
5. Cloak of invisibility: Engineers use plasmonics to create an invisible photodetector
6. Stanford engineers perfecting carbon nanotubes for highly energy-efficient computing
7. Engineers achieve longstanding goal of stable nanocrystalline metals
8. UCLA engineers develop new energy-efficient computer memory using magnetic materials
9. UT Arlington engineers working to prevent heat buildup within 3D integrated circuits
10. Cornell bioengineers discover the natural switch that controls spread of breast cancer cells
11. Forget about leprechauns, engineers are catching rainbows
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/4/2016)... San Francisco, CA (PRWEB) , ... February 04, ... ... future of enterprise talent development and compliance training, today announced an interactive ... on Morf Playbook™. The RAPS (Regulatory Affairs Professional Society) accredited interactive course ...
(Date:2/4/2016)... Feb. 4, 2016  Sangamo BioSciences, Inc. (NASDAQ: ... today that Edward Lanphier , Sangamo,s president and ... progress of Sangamo,s ZFP Therapeutic ® development programs ... 2:40 pm ET on Thursday, February 11, 2016, at ... Conference. The conference is being held in ...
(Date:2/4/2016)... ... February 04, 2016 , ... ... Forensics Club, takes place February 5-6 at the University’s student center, Kehr ... activities such as workshops and competitions for ample networking, learning and collaborating ...
(Date:2/4/2016)... 2016  CytoSorbents Corporation (NASDAQ: CTSO ), ... CytoSorb® blood filter to treat deadly inflammation in ... announced that CEO Dr. Phillip Chan , ... Group,s 2016 Disruptive Growth & Healthcare Conference, providing ... Conference Presentation Details: Where: Convene Conference ...
Breaking Biology Technology:
(Date:2/3/2016)... , February 3, 2016 ... market research report "Automated Fingerprint Identification System Market by ... Search), Application (Banking & Finance, Government, Healthcare, and Transportation) ... MarketsandMarkets, the market is expected to be worth USD ... 21.0% between 2015 and 2020. The transformation and technology ...
(Date:2/2/2016)... This BCC Research report provides a ... the recent advances in high throughput ‘omic platforms ... forward. Includes forecast through 2019. Use ... opportunities that exist in the bioinformatic market. Analyze ... well as IT and bioinformatics service providers. Analyze ...
(Date:2/2/2016)... , Feb. 2, 2016  Based on ... Frost & Sullivan recognizes US-based Intelligent Retinal Imaging ... & Sullivan Award for New Product Innovation. IRIS, ... North America , is poised ... rapidly growing diabetic retinopathy market. The IRIS technology ...
Breaking Biology News(10 mins):