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IIUM Engineering Journal, Vol. 2, No. 2, 2001 M. G. Bannikov et al.

APPLICATION OF ION BEAM PROCESSING TECHNOLOGY IN
PRODUCTION OF CATALYSTS

Mykola G. Bannikov1, Javed A. Chattha1

Vladimir N. Zlobin2, Igor P. Vasilev2, Jury A. Cherkasov2 and Piotr N. Gawrilenko2

1Fac. of Mech. Eng., GIK Institute of Eng. Sc. and Techn., Topi 23460, District Swabi, Pakistan
2East-Ukrainian National University, Molodejny 20A, Luhansk 9104, Ukraine

Abstract: In this paper, the applicability of Ion Beam
Processing Technology for making catalysts has been
investigated. Ceramic substrates of different shapes
and metal fibre tablets were implanted by platinum
ions and tested in nitrogen oxides (NOx) and carbon
monoxide (CO) conversion reactions. Effectiveness of
the implanted catalysts was compared to that of the
commercially produced platinum catalysts made by
impregnation. Platinum-implanted catalyst having fif-
teen times less platinum content showed the same CO
conversion efficiency as the commercially produced
catalyst. It was revealed that the effectiveness of the
platinum-implanted catalyst has complex dependence
on the process parameters and the optimum can be
achieved by varying the ions energy and the duration
of implantation. Investigation of the pore structure
showed that ion implantation did not decrease the spe-
cific surface area of the catalyst.

Key words: Catalyst, Ion Implantation, Noble metals.

1. INTRODUCTION

Growing concern of the world society over clean envi-
ronment impels manufacturers to look for new, envi-
ronmentally-friendly technologies. Catalysts are widely
used to clean industrial and automobile exhausts from
oxides of nitrogen (NOx), carbon monoxide (CO) and
unburned hydrocarbons (HC).
Catalysts are produced by the well-established impreg-
nation technology[1]. With this technology a ceramic
substrate is impregnated by a solution of nitrates of
catalytic metals. This step is followed by drying and
calcination. The whole cycle is carried out in several
steps and takes around 50 hours. High water consump-
tion and emission of NOx to the atmosphere accompa-
ny this process. Other drawbacks of this method have
to be accounted for. The properties of the carrier are
said to be changed, and in some cases the specific area
of a catalyst is reduced[2]. Unequal distribution of cata-
lytic materials on the carrier surface and their agglom-
eration has been also observed. The growing of the
catalytic material crystals with time leads to the block-
age of pores during catalyst exploitation[3]. High ex-
pense of catalytic materials is inherent to impregnation

technology and this is of very importance when noble
metals are used as catalysts.
In this connection new technologies of catalyst coating
have to be sought and investigated. Ion Beam Pro-
cessing Technology (IBPT) has been already recog-
nised as a competitive method of surface modification.
Ion implantation has been used to enhance materials
engineering performance in areas such as hardness,
friction and wear, and corrosion[4-6]. Direct metal ion
implantation as a part of IBPT has some features that
make it applicable for making catalysts. The ion im-
plantation allows virtually any chemical element to be
implanted into the surface of any solid. Apart from
ceramic pellets other carriers such as metallic type or
metallic wire may be used as a substrate of a catalyst[7].
It was also found that when a catalyst on a substrate is
in the form of atoms its catalytic activity increases[8].
This is additional evidence in favour of an ion implan-
tation.

2. ION IMPLANTATION INSTALLATION

The ion implanter used for catalyst fabrication includes
a vacuum chamber, source of metal ions, a vacuum
pumping-out system and power supplies. The 1 m3
vacuum chamber has a hatch for loading the substrate
to be coated, a branch pipe for connection with a vacu-
um pump, an observation port, an air inlet valve for gas
and a flange on which a metal ion source is located.
The ion source on the basis of a discharge in crossed
ExH fields with the cathode sputtering of metals has
allowed an ion beam to be obtained along with diame-
ter 200 mm, current density 130 A/cm2 and non-
uniformity of 5% along the cross section. The vacuum
chamber can accommodate several ion sources. The
ease of changing the target in the ion source enables
different materials to be implanted. The energy of ions
can be controlled from 0 to 40 keV.
With an ion implantation technique, catalysts are fabri-
cated in a single cycle. The vacuum chamber is loaded
with the substrates and a vacuum of up to 0.013 Pa is
created. Coating then starts. This process, in turn, com-
prises two steps: surface degassing and coating. The
first step is fulfilled at the voltage of 10 kV for about
10 minutes. The voltage of the second step determines
the depth of ion penetration into the carrier and de-

IIUM Engineering Journal, Vol. 2, No. 2, 2001 M. G. Bannikov et al.

pends on materials processed. In our case it was around
20 kV. The duration of the second step depends on the
catalytic material loading required.
Ion implantation dose ( D ) is proportional to the cur-
rent density ( I ), surface area processed ( S ) and dura-
tion of implantation ( t ):

191.6 10
I t

D
S 




 
. (1)

The mass of the substance implanted ( m ):
271.66 10am D m

    (2)

where am is the average atomic mass of the chemical
element implanted. Catalyst loading in wt% is deter-
mined as a ratio of mass of catalytic material to mass
of substrate.

3. EXPERIMENTAL PROCEDURE

Carbon monoxide conversion efficiency of catalyst was
measured in the test bed, which comprised the twin
cylinder naturally aspirated diesel engine with a bore of
85 mm and a stroke of 110 mm, laboratory catalytic
reactor, and gas analysers. Design of the laboratory
catalytic reactor is described by Zlobin et al.[9]. Exhaust
temperature at the reactor inlet could be changed from
100ºC to 500ºC by an electric heater. GIAM-14 gas
analyser was used for measuring CO concentration in
the exhaust at the reactor’s inlet and outlet. All engine
performance parameters, except exhaust temperature,
were maintained as follows: engine speed 1000 rpm,
engine brake power 1 kW, air mass flow rate around 37
kg/hr, relative ratio of  = 4.2. Exhaust flow could by-
passed the reactor to maintain constant volume flow
rate through the reactor. The space velocity was 38,000
hr-1.
Some industrial processes are accompanied by emis-
sion of harmful NOx. Reduction of NOx can be
achieved using a suitable catalyst in presence of am-
monia (NH3) as shown in the following equation:

3 2 26NO 4NH 5N 6H O   (3)

In this investigation, NOx conversion efficiency of cat-
alysts was measured by model gas activity tester. Mod-
el gas was composed of oxygen (O2), nitrogen (N2) and
nitric oxide (NO). Mass flow rate of NH3 was 0.2%
that of the model gas, and volume of the catalytic reac-
tor was 40 cm3, space velocity was 15,000 hr-1. Nitric
oxide content in the outlet gas was measured by chemi-
luminescent gas analyser (344-CL-01).
The conversion efficiency of a catalyst was calculated
as a ratio of mass of contaminant in gas outflow to that
in gas inflow. The pore structure of catalysts was in-
vestigated by mercury porosimetry and nitrogen phy-
sisorption (BET) methods.

4. RESULTS AND DISCUSSION

Several samples of catalyst on various substrates with
different platinum loading were prepared. The first set
of experiments was a preliminary investigation on the

applicability of an ion implantation technique as a
means of manufacturing catalysts. Alumina (-Al2O3)
extrudate (ø4-6 mm, L5-7 mm), alumina rounded
granules (ø3-7 mm) and tablets (ø70 mm, L5 mm)
made from metal fibre (ø0.1 mm) were implanted with
platinum. This resulted in catalysts C1 (Pt = 0.110%),
C2 (Pt = 0.110%), and C3 (Pt = 0.114%) respectively.
The implantation dose was chosen in a such way as to
obtain a platinum loading of catalysts two times less
than that of commercially produced platinum catalyst,
C5 (Pt = 0.2%). The commercial catalyst C5 was man-
ufactured by impregnation method.
Catalysts obtained were tested in reaction of NOx with
NH3 at temperature of 280ºC, and results are shown in
Fig. 1. All catalysts showed satisfactory conversion
efficiency but platinum content was still too high to
make an ion implantation technique the competitive
one.

C1 C2 C3

N
O

c
on

ve
rs

io
n

ef
fic

ie
nc

y,
%

Fig. 1: NOx conversion efficiency of catalysts.

The natural question arises: what regime parameters of
an implantation process are to be chosen to obtain
maximum efficiency of the catalyst at the minimum
expense of a catalytic material?
Preliminary work carried out to change the process
parameters and the catalyst with low platinum content
has been obtained. Figure 2 shows that the new catalyst
C4 (Pt = 0.0135%) has the same CO conversion effi-
ciency at 340ºC as that of catalyst C5 (Pt = 0.2%), even
though it contained fifteen times less platinum. Also
shown in Fig. 2 is the conversion efficiency of the
commercially produced cuprum-chromium catalyst C6
(CuO : Cr2O3 = 5% : 5%). It is only half as effective as
platinum catalysts.
Effectiveness of any catalyst, other things being equal,
depends on the catalytic material loading, specific sur-
face area and temperature of reaction. First two proper-
ties, in turn, depend on the method of coating. Coating
obtained by impregnation has a finite thickness and
only catalyst on the exterior surface is exposed to rea-
gents whereas the rest does not contribute to reaction.
Obviously with this technology the maximum catalytic
loading must exist over which catalyst effectiveness
does not increase. While selecting ion implantation
process parameters the following factors are to be tak-
en into account. Energy of ions determines the depth of
their penetration into the surface of a substrate. If ions
are implanted at depth more than 1 m, they probabl y
will not be accessible to reagents. Loading of catalytic

IIUM Engineering Journal, Vol. 2, No. 2, 2001 M. G. Bannikov et al.

material is directly proportional to the duration of im-
plantation and current density. In turn both duration of
ion bombardment and current density can affect the
specific area significantly. For instance nickel ion
bombardment with the dose of 5x1016 ions/cm2 in-
creased the specific area by factor of four compared to
that of an unprocessed sample[4]. Thus, duration of im-
plantation affects both platinum loading and surface
properties of the carrier.

100

C4 C5 C6

C
O

c
on

ve
rs

io
n

ef
fic

ie
nc

y
%

Fig. 2: CO conversion efficiency of catalysts.

To estimate the influence of duration of implantation
on efficiency of the platinum catalyst the following
experiment was carried out. Several catalysts were im-
planted with platinum at different duration of implanta-
tion and the same current density. Catalysts were tested
in CO conversion reaction at different temperatures.
Figure 3 shows that the relative conversion efficiency
of catalysts is a non-linear function of the implantation
dose. Temperature of reaction at which maximum effi-
ciency of each catalyst was observed is a function of
duration of implantation as well. Moreover, the maxi-
mum conversion efficiency in this experiment was ob-
tained at lower temperatures.

370

380

390

400

410

420

430

440

450

0 5.70E+16 1.14E+17 2.50E+17 3.90E+17

Implantation dose, ions/cm²

T
em

pe
ra

tu
re

, º
C

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

R
el

at
iv

e
ef

fi
ci

en
cy

Temperature Relative efficiency
Fig. 3: Effect of implantation dose on the relative effi-

ciency.

This experiment could not be used to predict the opti-
mum parameters of an ion implantation process but
showed that properties of catalysts produced by an ion

implantation could not be explained just by catalytic
material loading. Possible surface modification caused
by an ion bombardment must be taken into account and
investigated. As a first step in this direction, the pore
structure of carrier and catalysts was investigated by
the mercury porosimetry technique.
Figure 4 shows that curves of pore volume distribution
versus pore radius have nearly the same shape for all
samples tested. Pore structure of samples is character-
ised by two kinds of pores: macropores with radius
from 200 to 1000 nm, and mesopores with radius from
3.7 to 8 nm.

Fig. 4: Pore volume distribution: (a) carrier (-Al2O3
pellets), (b) catalyst C4, (c) catalyst C6.

With mercury porosimetry method only pores with
radius of more than 3.7 nm are accessible. Thus if
sample contains pores with radius less than 3.7 nm its
surface area can be underestimated. Therefore surface
area of samples was also measured by the BET method
with which pores with radius up to 0.32 nm are acces-
sible.
As shown in Fig. 5, specific surface areas of catalysts
measured by mercury porosimetry and BET methods
differ significantly. This difference indicates the pres-
ence of tiny pores with radius from 0.32 to 3.7 nm in
the catalyst samples. This is also confirmed by the in-

IIUM Engineering Journal, Vol. 2, No. 2, 2001 M. G. Bannikov et al.

complete shape of the integral curves in Fig. 4. Figure
5 shows that specific surface areas of carrier and cat-
lysts C4 and C6 are not much different from each oth-
er. When assessing these data the accuracy of meas-
urement must be taken into account. P. Fauchais and J.
C. Labbe suggest that measurement error of methods
used can reach 20%[10]. Thus, the surface area differ-
ence observed is comparable with measurement error.
To investigate the effect of an ion bombardment on the
surface area additional tests will have to be carried out.
Nevertheless, the firm conclusion can be made that ion
implantation does not decrease the surface area of cata-
lyst.

100

120

140

Mercury porosimetry BET

Su
rf

ac
e

ar
ea

, m
2 /

Carrier
C4
C6

Fig. 5: Surface area of catalysts.

5. CONCLUSION

Based on the results of the work reported in this paper
the following conclusions are drawn:
1. The ion implanter for coating of catalysts has been

developed. The installation allows implanting any
catalytic materials on various substrates.

2. Several samples of catalysts on various substrates
have been prepared and tested. Platinum-implanted
catalyst having fifteen times less platinum content
showed the same CO conversion efficiency as the
commercially produced catalyst.

3. Effectiveness of implanted catalysts and temperature
at which maximum efficiencies have been achieved
had non-linear dependence on the implantation
dose.

4. Investigation of the pore structure showed that ion
implantation did not decrease the specific surface
area of the catalyst. Modification of surfaces treated
with an ion beam demands further investigation.

5. Ion beam processing technology may be considered
as the potential method of production of noble-
metal-based catalysts and research in this direction
shall be continued.

ACKNOWLEDGMENTS

This research has been done in collaboration between
Ghulam Ishaq Khan Institute of Engineering Sciences
and Technology and East-Ukrainian National Universi-
ty. The authors would like to thank both universities
for the provision of laboratory facilities and encour-
agement.

LIST OF SYMBOLS AND ABBREVIATIONS

1.610-19, C: elementary charge

1.6610-27, kg: atomic mass unit

D , ion/cm2: ion implantation dose

I , A/cm2: ion beam current density

(IBPT): Ion Beam Processing Technology

m , kg: mass of the substance implanted

ma: atomic mass

S , cm2: surface area processed

t , s: duration of implantation

: relative ratio

REFERENCES

[1] P. Mychlenov, “Catalysts Technology”, Leningrad,
Chemistry, 1979.

[2] O. I. Jegalin, N. A. Kitrossky, V. I. Panchishny, N. N.
Patrahalcev and A. I. Frenkel, “Automotive Catalytic
Converters”, Moscow: Mashinostroenie, 1979.

[3] S. Laubenstein, “Katalytishe Abgasreinigung für Sta-
tionär-Motoren”. Info-Broshüre, H.U.T. Heuwieser
Umwelttechnik GmbH, 1998.

[4] J. K. Hirvonen, “Ion Implantation”, New York, Aca-
demic Press, 1980.

[5] V. N. Zlobin, M. G. Bannikov, P. H. Draper, A. V.
Zotov and I. P. Vasilev, “Hardening of Cutting Tool In-
serts by Ion Implantation”, Proceedings of 7th Interna-
tional Symposium on Advanced Materials, Islamabad,
17-21 September 2001.

[6] R. R. Manory, C. L. Li, C. Fountzoulas, J. D. Demaree,
J. K. Hirvonen and R. Nowak, “Effect of nitrogen ion-
implantation on the tribological properties and hardness
of TiN films”, Materials Science & Engineering, Vol.
A253, pp. 319-327, 1998.

[7] B. I. Musienko, V. D. Parhomenko, B. V. Farmakovsky
and A. P. Hinsky, “Competitive Cleaner of Exhaust of
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[8] S. B. Grinenko, A. A. Denisov, A. G. Ohapkin and A.
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[9] V. N. Zlobin, M. G. Bannikov, I. P. Vasilev, J. A.
Cherkasov and P. N. Gawrilenko, “Potential of use of
ion implantation as a means of catalyst manufacturing”,
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[10] P. Fauchais and J. C. Labbe, Workshop on thermal
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IIUM Engineering Journal, Vol. 2, No. 2, 2001 M. G. Bannikov et al.

BIOGRAPHIES OF AUTHORS

Dr. Mykola G. Bannikov received his master’s degree
in Mechanical Engineering from Lugansk Engineering
Institute, Ukraine in 1980. He obtained his Ph.D degree
from Kharkov Railway Transport Institute, Ukraine in
1989. He is a Professor at the Faculty of Mechanical
Engineering, Ghulam Ishaq Khan (GIK) Institute of
Engineering Sciences and Technology, Pakistan. His
area of specialisation is Thermo-Fluid Sciences and
particularly their application to modelling of flow and
combustion processes of Internal Combustion Engines
(ICE). Currently he is concerned with ICE pollutant
formation and control.

Dr. Javed Ahmad Chattha received his Bachelor’s
degree in Mechanical Engineering from University of
Engineering and Technology Lahore, Pakistan in 1978.
He obtained his master’s degree in Energy Technology
from the Asian Institute of Technology, Bangkok,
Thailand in1984 and then he did his Ph.D from the
University of Birmingham, UK in 1990. Presently he is
Dean of Faculty of Mechanical Engineering at GIK
Institute of Engineering Sciences and Technology, Pa-
kistan. His area of interest is Thermo-fluids.

Dr. Vladimir N. Zlobin received his master’s degree
in Physics from Omsk State University, Russia in 1962
and Ph.D degree from the same University in 1973. He
is currently a senior lecturer at Volgograd Polytechnic
College, Russia. He is the author of the ion implanta-
tion installation used in this research.

Dr. Igor P. Vasilev obtained his master’s degree in
Mechanical Engineering from Lugansk Engineering
Institute, Ukraine in 1973 and then graduated with a
Ph.D degree from East-Ukrainian National University
(EUNU), Ukraine in 1992. Hi is an Associate Professor
at EUNU. His research works focus on the develop-
ment of new technologies of catalyst coating.

Mr. Jury A. Cherkasov received his master’s degree
in Mechanical Engineering from East-Ukrainian Na-
tional University in 1999. Currently he is doing his
Ph.D at EUNU.

Dr. Piotr N. Gawrilenko received a degree in Me-
chanical Engineering from Lugansk Engineering Insti-
tute, Ukraine in 1973. He graduated with a Ph.D degree
from Volgograd Polytechnic Institute, Russia in 1988.
His research interests are working process and emis-
sion control of ICE.

IIUM Engineering Journal, Vol. 2, No. 2, 2001