NEW
CHEMISTRY - DOUBLE DELIGHT -
A
GAS SENSOR AND A PROTECTIVE COATING
“Science is an adventure into the unknown, entering an
uncharted territory of astonishing beauty, surprises and amazing perspectives”, said Nobel Laureate, Prof.
Ben L. Feringa, at the 61st Anniversary of the Bandung Institute of Technology
(ITB).
It is in this spirit of adventure that Prof Anjana Devi,
Inorganic Materials Chemistry, Ruhr University, Bochum, Germany and her student
Lukas Mai, have developed a novel process for the deposition of ultra-thin
films of Zinc Oxide that can be used as: Nitrogen Dioxide Sensors and as
protection for plastics used by the food and the pharmaceutical industry.
Lukas Mai - Reflected in a Thin Film and Prof Anjana Devi © RUB, Marquard
Hitherto the method of
producing thin films of Zinc Oxide involved the use of difficult to handle, pyrophoric materials, that were
hazardous, corrosive and required special protective and safety equipment,
besides the need to store them under an atmosphere of inert gas.
In order to make these
coatings, simpler, safer, affordable and non-toxic, the interdisciplinary research
team at Ruhr-Universität Bochum (RUB) has now established a new fabrication
process based on a non-pyrophoric
zinc precursor, which can be processed at temperatures low enough to allow
plastics to be coated.
Professor Anjana Devi’s
team used Atomic Layer Deposition (ALD) to apply ultra-thin ZnO layers on
sensor substrates, which can eventually be used to produce a sensor for
Nitrogen Dioxide (NO2).
The Ruhr University
scientists have published their research work in the June 4, 2020, issue of the
international journal Small.
COVER PAGE - Journal SMALL June 4, 2020, ZnO, RUB
“The
key for the development of a safe alternative ALD process for ZnO at RUB was to
develop a new, non-pyrophoric precursor that is safe to handle and is able to
deposit ZnO thin films of the highest quality,”
explains Lukas Mai, lead author of the study. “The challenge was to find
alternative chemistries to replace the pyrophoric compounds that are generally
used in the industry for ZnO.”
The
unique aspect of the new process is that it can be performed at very low
process temperatures, thus facilitating deposition onto plastics. Consequently,
the new process can be used not only for the manufacture of gas sensors, but
also of gas barrier layers. In the packaging industry, such layers are applied
on plastics to help protect degradable goods such as food or pharmaceuticals
from air.
“The chemistry behind ALD
processes is therefore essential and has a huge impact on the resulting thin
films,” points out Prof. Anjana Devi.
Prof. Anjana Devi
Prof Dr.Anjana Devi, RUB, Bochum
In
a glittering career of two decades and more at the Inorganic Materials Chemistry
Department, Ruhr University, Prof Anjana Devi has carried out pioneering work
in research areas encompassing: Precursor development – Metal organic Chemical
Vapor Deposition (MOCVD) as a precursor for deposition of thin films using
Atomic Layer Deposition (ALD) and Chemical Vapor Deposition (CVD) techniques.
The main focus of her research is on the transformation of metalorganic
precursors into nanostructured thin films of various functional materials for
device manufacturing and eventual applications as - photo anodes; transparent
electrodes, thin film transistors (TFTs) and transparent conducting thin films
for solar cell applications, sensors, optoelectronics, etc.
Prof
Anjana Devi and her group collaborate with scientists from various disciplines,
be they, Physicists, Chemists or Engineers and their goal is to develop
nanostructured materials for different applications ranging from –
Microelectronics, Sensors, Dielectrics, barrier coatings, catalysis and much
more.
GROUP PHOTO - DEC 2019
Publishing
her research work in international high impact scientific journals, Prof Anjana
Devi has notched up over 190 papers and counting.
She
has graduated in all, Twenty Two (22) B.Sc Students; Thirty Three (33) M.Sc
Students and Seventeen (18) Ph.D students in her career so far.
Besides,
the Best invention Prize – 2005, she received from her University, she is the
recipient of numerous other awards and has been on the editorial board of
several prestigious scientific journals. Prof Anjana is on the international
advisory board of the ALD and CVD community and has led several national and
international research projects.
Honorary Doctorate in
Technology – 2020, Aalto University, Finland:
On
being conferred the Honorary Doctorate in Technology -2020 by the prestigious
Aalto University, Finland, Prof Anjana Devi in all humility says, “Hard work always pays off….” That is
probably her mantra for success.
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