The researchers created the one-atom-thick carbon lattice flakes by placing bulk graphite in a solution and bombarding it with ultrasonic waves that broke off thin sheets.
The researchers then filtered the solution to produce a graphene film, composed of a haphazard arrangement of stacked flakes, that they used as the top layer of a chemical sensor. When the graphene was exposed to test chemicals that altered the surface chemistry of the film, the subsequent movement of electrons through the film produced an electrical signal that flagged the presence of the chemical.
The researchers experimented by adjusting the volume of the filtered solution to make thicker or thinner films. They found that thin films of randomly stacked graphene could more reliably detect trace amounts of test chemicals than previously designed sensors made from carbon nanotubes or graphene crystals.
The results are accepted for publication in the AIP's journal Applied Physics Letters.
The researchers theorize that the improved sensitivity is due to the fact that defects in the carbon-lattice structure near the edge of the graphene flakes allow electrons to easily "hop" through the film.
Article: "Chemical Sensors Based On Randomly Stacked Graphene Flakes" is accepted for publication in Applied Physics Letters.
Authors: Amin Salehi-Khojin (1, 7), David Estrada (2, 3), Kevin Y. Lin (1), Ke Ran (4, 5), Richard T. Haasch (5), Jian-Min Zuo (4, 5), Eric Pop (2, 3, 6), and Richard I. Masel (7).(1) Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign
Catherine Meyers | EurekAlert!
Writing and deleting magnets with lasers
19.04.2018 | Helmholtz-Zentrum Dresden-Rossendorf
Ultrafast electron oscillation and dephasing monitored by attosecond light source
19.04.2018 | Yokohama National University
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
19.04.2018 | Materials Sciences
19.04.2018 | Physics and Astronomy
19.04.2018 | Physics and Astronomy