Researchers at Chalmers University of Technology, Sweden, along with colleagues from other universities, have discovered the possibility of preparing thin platinum with an atom for use as a chemical sensor. The results were recently published in the scientific journal Advanced Material Interfaces.
A scheme of platinum atoms deposited on the surface of the carbon “buffer layer”
“In a nutshell, we managed to make a metal layer only one atom thick – a kind of new material. We found that this atomically thin metal is super sensitive to its chemical environment. Its electrical resistance changes significantly when it interacts with gases. , ”Explains Kyung Ho Kim, postdoc at the Quantum Device Physics Laboratory at the Department of Microtechnology and Nanoscience at Chalmers, and lead author of the article.
The essence of the research is the development of 2-D materials in addition to graphene.
“Atomic thin platinum could be useful for ultra-sensitive and rapid electrical detection of chemicals. We have investigated the matter of platinum in detail, but other metals such as palladium give similar results,” says Samuel Lara Avila, associate professor at Quantum Device. Physics Laboratory and one of the authors of the article.
The researchers used the sensitive chemical-to-electrical transduction capacity of atomically thin platinum to detect toxic gases at the part-per-level level. Billion. They demonstrated this by detecting benzene, a compound that is carcinogenic even in very small concentrations and for which there is no cheap detection device.
“This new approach, which uses nuclear-thin metals, is very promising for future applications for monitoring air quality,” says Jens Eriksson, head of the Applied sensor science unit at Linköping University and co-author of the paper.
Increasing the sensitivity of solid-state gas sensors by incorporating nanostructured materials as the active sensor element can be complicated by effects on the interfaces. Interfaces at nanoparticles, grains, or contacts can result in non-linear current-voltage response, high electrical resistance, and ultimately electrical noise that limits sensor readout.
This work reports the possibility of preparing electrically continuous platinum layers at an atomic thickness by physical vapor deposition on the carbon zero layer (also known as the buffer layer) grown epitaxially on silicon carbide. With a 3–4 Å thin Pt layer, the electrical conductivity of the metal is strongly modulated when it interacts with chemical analytes due to charges transferred to / from Pt. The strong interaction with chemical species, together with the scalability of the material, enables the production of chemical resistor units for electrical reading of chemical species with detection limits of sub part per billion (ppb). The 2-D system formed by atomically thin Pt on the carbon zero layer at SiC opens the way for elastic and highly sensitive chemical detection and can be the way for the design of new heterogeneous catalysts with superior activity and selectivity.
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Kyung Ho Kim et al. Chemical sensing with atomic thin platinum templated by a 2D insulator, Advanced material interfaces (2020). DOI: 10.1002 / admi.201902104
Provided by Chalmers University of Technology
Citation: Single-atom-thin platinum is an amazing chemical sensor (2020, September 14) retrieved September 15, 2020 from https://phys.org/news/2020-09-atom-thin-platinum-great-chemical-sensor .html
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