M*****
PS700
17/02/2008
Outline of PhD Proposal
1. Background/Introduction to the research topic
What is it about and why is it important?
1 in 6 people in all deaths on the road involve drivers who are over the legal alcohol
consumption limit. Drunk driving is a regular occurrence in the UK and these are only the
recorded offences. It would really aid the police if a proper ethanol sensor could be
prepared as the ones they are in possession of tend to be quite inaccurate and
inadequate.
Semiconductor oxides have recently been considered optimal as they are relatively cheap
to use, very simple and fast to usei. They also show a wide linear response to ethanol
which can aid police in apprehending drunk drivers. Bismuth ferrite has become a very
popular compound to use for ethanol sensing due to the fact that it is reliable and stable.ii
Bismuth Ferrite also has been shown to be multiferroic; this means that BFO
simultaneously shows ferroelectric and antiferromagnetic properties Bismuth ferrite has
previously been doped with several materials, and tested for their ethanol sensing
propertiesiii.
2. Objectives of the Project: What will come out of the project? What is novel in
the project? What will be investigated
The main problem when preparing an ethanol sensor is that the sensor will not be unique
to ethanol. E.g. the sensor will detect acetone and ethanol simultaneously so it is
impossible to determine which gas it is detectingiv.
This PhD will focus on trying several different materials such as sodium, lithium, calcium,
niobium, zinc, etc. These materials will be dope Bismuth Ferrite with different
combinations of dopants and at various doping percentages. After which, the sample will
be run on Impedance Spectroscopy to determine their gas sensing properties.
So far, all the literature has shown that a gas sensor unique to detecting ethanol has not
yet been found. It also has been showing conflicting results with certain materials.
3. Methodology: What methods will be employed? What will you need? Where will
it be undertaken? Estimate the funding required.
The first step of sample preparation is to dope the Bismuth Ferrite (BFO). The materials
will be weighed out in stoichiometric ratios. The sample will then be heated for 5 hours at
800°C. The sample is then leached with 50 ml nitric acid for 2 hours. The sample is then
reheated at 1 hour for 400°C. X-ray Diffraction (XRD) will then be used to reveal the
structural properties, scanning electron microscopy (SEM) will be used to review particle
morphology and impedance spectroscopy will be used to measure the ethanol sensor
properties of the samples.v Each sample will be prepared in this fashion.
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M*****
PS700
17/02/2008
The equipment needed for this research project to be successful is the X-ray Diffraction,
Impedance spectrometer, and a Scanning Electron Microscope. In addition to the access to
these various instruments, a supply of various materials will be needed to prepare various
types of BFO perovskite samples. This project will be undertaken at the University of Kent
under the supervision of Dr. Donna Arnold. This facilitates the project tremendously as
these instruments are already present at the University, the only requirements that are
essential will be the training for these instruments and the payment required for using
them.
The average costs for the research project were calculated below. This is just an estimate
of the costs that might be necessary throughout the three years. These costs include the
university fees, the stipend the travel expenses and conference possibly attended in
second and third year, and the indirect costs and consumables. The indirect costs are
factors such as technical staff costs and estates costs.
Purpose
University fees
Indirect costs
Stipend
Consumables
PC
Travel +
conferences
Total
Year 1
3,500
6,767
13300
2,500
1,000
0
Year 2
3,500
6,433
13300
1,500
0
1,000
Year 3
3,500
6,767
13300
1,500
0
2,000
Costs (£)
10,500
19,967
39,900
5,500
1,000
3,000
27,067
25,733
27,067
79,867
4. Expected outcomes: how this project will move forward this particular area of
research?
The main movement that may occur in this particular field of research is providing more
information on different doped BFO perovskites. Additionally, more information should be
available on gas sensors in general and more specifically on ethanol sensors unique to
detecting ethanol. This in return may aid in producing a portable ethanol sensors for
bouncers at clubs and for the police out on patrol.
i
S.C.Tsang et al., Rare Earth Oxide sensors for ethanol analysis, Sensors and actuators B, 1998, 226-235
ii
X. Yu et al., Gas-sensing properties of perovskite 𝐵𝑖𝐹𝑒𝑂3 Nanoparticles, J.Am.Ceram.Soc., 92,2009,3105-3107
iii
D.C.Arnold et al., Ferroelectric-Paraelectric Transition in 𝐵𝑖𝐹𝑒𝑂3 : Crystal structure of the Orthorhombic β
phase, PRL, 2009, 102
iv
S.C.Tsang et al., Rare Earth Oxide sensors for ethanol analysis, Sensors and actuators B, 1998, 226-235
v
D.C.Arnold et al., High temperature phase transitions in 𝐵𝑖𝐹𝑒03 , Mater. Res. Soc. Symp.Proc.Vol.1199, 2010,
Materials Research Society
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