Nav: Home

The properties of thin titanium oxide films have been studied

January 21, 2020

A team of scientists from the Research and Education Center "Functional Nanomaterials" of Kant Baltic State University works on the development of new prospective nanomaterials. Together with foreign colleagues they have recently discovered a method for synthesizing titanium oxide (Ti2O3) thin films. Some of the new materials are considerably different from their bulk analogs and show the required conductivity within a wider range of temperatures. In the future they may be used to create effective catalysts that would not depend on temperature. The results of the study were published in the Thin Solid Films journal.

Some titanium oxides are known for their unique properties, such as increased photocatalytic activity (i.e. they effectively use light to speed up chemical reactions). Titanium oxide-based coatings are able to clean themselves under the influence of light. Moreover, they can potentially be used to purify air and water from harmful substances and to desalinate sea water. The same property has recently been found in nanomaterials based on titanium oxide (III). Among other things, titanium oxide (III) is able to change phase from a semiconductor to a metal. In the course of such a phase change it considerably increases its electrical conductivity when heated. Not only the level of conductivity, but even the relative position of atoms is subject to changing. One of the main goals of modern science is to look for structure-property patterns of this kind.

In this work the authors used the magnetron sputtering method to obtain thin titanium oxide films. In other words, the scientists bombarded a titanium target with charged particles. The ablated atoms were deposited on a special substrate and reacted with free oxygen radicals that were formed when oxygen molecules collided with the charged particles. As a result of this reaction thin oxide films were formed. Based on different oxygen concentrations and substrate temperatures, the scientists managed to obtain TiO, Ti2O3 and TiO2 oxides and among them - two completely different Ti2O3 structures that differed by the positions of atoms in the crystal lattice. One had a trigonal lattice similar to that of corundum, and the other one - an orthorhombic lattice that was obtained in its pure form. To do so, the scientists modified the sputtering method by using titanium oxide instead of titanium metal to ablate atoms in a completely oxygenless environment.

The scientists studied the properties of different types of titanium oxide (III) and discovered differences between the orthorhombic film produced by magnetron sputtering and another one described in 2017. The film created by the team remained a semiconductor within the whole range of described temperatures (from -268°? to 300°?) while the previously known structure became a conductor at temperatures above 100?? and a superconductor at temperatures close to absolute zero (below -265°?). It also turned out that the conductivity of the corundum-type film was similar to that of a bulk Ti2O3 heated to 170-200°?. At these temperatures the bulk gains metal properties, while the film preserved high conductivity within the range from -268°? to several hundred degrees Celsius.

"Compared to already known structures manufactured using other methods, our films maintain their properties within a wider range of temperatures. Thus, the corundum-type film remains a metal conductor at low temperatures, and the orthorhombic film - a semiconductor at high temperatures," said Petr Shvets, a Candidate of Physics and Mathematics, and a senior researcher at the Research and Education Center "Functional Nanomaterials".
-end-
The participants of the project also represented Trinity College (Dublin, Ireland), Bundeswehr University Munich (Germany), and Dublin City University.

Immanuel Kant Baltic Federal University

Related Titanium Articles:

Skoltech scientists developed a new cathode material for metal-ion batteries
Researchers from the Skoltech Center for Energy Science and Technology (CEST) created a new cathode material based on titanium fluoride phosphate, which enabled achieving superior energy performance and stable operation at high discharge currents.
First view of hydrogen at the metal-to-metal hydride interface
University of Groningen physicists have visualized hydrogen at the titanium/titanium hydride interface using a transmission electron microscope.
The properties of thin titanium oxide films have been studied
Some titanium oxides are known for their unique properties, such as increased photocatalytic activity (i.e. they effectively use light to speed up chemical reactions).
Adding copper strengthens 3D-printed titanium
Successful trials of titanium-copper alloys for 3D printing could kickstart a new range of high-performance alloys for medical device, defence and aerospace applications.
Fatigue-resistant, high-performance cooling materials enabled by 3D printing
High-performance solid-state elastocaloric cooling materials with exceptional fatigue resistance are made possible by 3D printing a nickel-titanium based alloy, researchers report.
Common food additive found to affect gut microbiota
Experts call for better regulation of a common additive in foods and medicine, as research reveals it can impact the gut microbiota and contribute to inflammation in the colon, which could trigger diseases such as inflammatory bowel diseases and colorectal cancer.
Layering titanium oxide's different mineral forms for better solar cells
A Japan-based research team led by Kanazawa University improved the efficiency of a new type of solar cell with a double layer consisting of pure anatase and brookite, two different mineral forms of titanium oxide.
Penn engineer's 'metallic wood' has the strength of titanium and the density of water
In a new study published in Nature Scientific Reports, researchers at the University of Pennsylvania's School of Engineering and Applied Science, the University of Illinois at Urbana-Champaign, and the University of Cambridge have built a sheet of nickel with nanoscale pores that make it as strong as titanium but four to five times lighter.
Alcohols as carbon radical precursors
Carbon radicals are attractive intermediates for organic synthesis because of their diversity and high reactivities.
Aluminum on the way to titanium strength
NUST MISIS scientists have proposed a technology that can double the strength of composites obtained by 3D printing from aluminum powder, and advance the characteristics of these products to the quality of titanium alloys: titanium's strength is about six times higher than that of aluminum, but the density of titanium is 1.7 times higher.
More Titanium News and Titanium Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.