Development of cathodes for Methanol and Ethanol Fuelled Low Temperature (300-600 ºC) Solid
Oxide Fuel Cells
Mahmut D. Mat 1, Xiangrong Liu2,3, Zhigang Zhu3 and Bin Zhu*2, 3
1
Nigde University, Mechanical Eng. Dept.51100 Nigde Turkey
2
Department of Chemical Engineering & Technology,
Royal Institute of Technology (KTH), S-100 44 Stockholm, Sweden
3
Goeta Technology Development International, S- 171 60, Solna, Sweden
* binzhu@kth.se
Abstract
We have made extensive efforts to develop various compatible cathode materials for the ceria-carbonate
composite (CCC) electrolytes to be used in direct alcohol fueled solid oxide fuel cells (DLFC). The
following cathode materials were mainly investigated: i) BSCF (BaSrCoFeO) perovskite oxide; ii) LFN
(LaFeO-based oxides, e.g. LaFe0.8Ni0.2O3) perovskite oxides; iii) Bi- or Tri- phase metal oxides with or
without lithiation. A number of copper and nickel based anode composites were also developed for
methanol and ethanol with maximum catalytic activity. The tri-metal oxide (CuNiOx-ZnO) cathode
produced the maximum power density output of 500 mW/cm-2 at 580 oC for DLFC with methanol
operation.
Introduction
Direct methanol and ethanol fuelled fuel cells (DLFC) offer many advantages for transportation
applications [1]. The development of DLFC-technology can realize a new generation of electric-vehicles.
Integration of DLFCs into vehicles will greatly simplify the electric vehicle system, and potentially make
the system at low cost level compared to existing FC-vehicles, because complex and expensive external
fuel processing will not be needed. The efficient use of the fuels can save the fuel consumption, thus
lower the operation cost, and at the same time reduce emissions of environmental pollutants. Liquid
1
fuels are also much simpler to handle than gaseous hydrogen, and are therefore beneficial from an
infrastructure perspective.
There is increasing interest in the literature for direct use of liquid alcohols such as methanol,
ethanol in SOFCs since they can easily be obtained from renewable resources. Such fuels can directly be
used in high temperature solid oxide fuel cells (HTSOFCs) which employ YSZ electrolytes and Ni/YSZ
anode without any modification in membrane and electrode materials. Basically, at operating
temperature of HTSOFC (800-1000 oC) liquid fuels undergoes thermal decomposition and Ni catalyses
the electrochemical reaction of H2 and CO. Employing a standard HTSOFC, Jiang and Virkar [2]
obtained 1.3 W/cm2 and 0.8 W/cm2 power densities with methanol and ethanol respectively. These
values are very promising for direct use of liquid alcohols much better then those obtained by DMFC
(direct methanol fuel cell based on polymer electrolyte fuel cells). Using SEM analysis they observed no
carbon deposition on the anode with methanol. However there was some carbon deposition with ethanol.
Carbon deposition was successfully eliminated adding some water into ethanol.
Saunders et al [3] investigated performance of methanol, ethanol and iso-octane in SOFCs.
Methanol produces a power density very similar to the pure hydrogen but anode was blocked with
carbon deposition in ethanol and iso-octane cases. They observed that carbon deposition decreases at
higher operating temperatures. Sasaki et al., [4] prepared different fuel samples using methanol, ethanol,
propane and buthanol. Basically they mixed each fluid with a certain amount of water that C-H-O ratio
was the same for all the fuels. Fixing the flow rate and all conditions the same in the cathode they
analyzed effects of alcohol type on the fuel cell performance. They found that methanol gave the highest
performance even very close to a fuel sample that consists of H2+CO. The performance of the fuel cell
decreased depending on the carbon number on their formulation and carbon deposition increased with
higher carbon fuels. Using equilibrium diagram they concluded that a certain amount of water should be
added to these fuels in order to prevent carbon deposition.
Cu is known as an effective catalyst for methanol cracking and substantially reduces the carbon
formation in the anode of SOFC at lower operation temperature. Cu however, undergoes a thermal
sintering at operation temperature above 600 oC, therefore it is mainly employed in intermediate and low
temperature SOFCs applications. Using gadolinium doped ceria (GDC) electrolyte and Cu-GDC anode
Brett et al. [5] found there was little or no carbon formation on the anode but delamination occurred
during the operation with dry methanol. The delamination problem was solved by impregnating the
electrode with CeO2. Brett et al. [5] found that Ceria impregnated Cu anodes are effective for methanol
decomposition and provide higher performance but poor electrocatalyst for H2 oxidation. Therefore Zhu
2
and co-workers [6] developed a new catalyst both include NiO and CuO. They found that although this
catalyst was good for both methanol and H2 cracking however the performance was limited to low
electrical conductivity of metal oxides used for catalytic activities. Zhu and co-workers [6] therefore
developed a novel catalyst incorporating some carbon black to improve electronic conductivity and
oxidation resistivity at high temperatures. They used ceria-carbonate composite electrolyte and a power
intensity of 0.25W cm-2 was achieved by directly operating the methanol at 560 ºC.
Zhu and co-workers [7-10] made efforts to further decrease operating temperature of SOFCs.
Using Ceria based composite (CBC) systems, Zhu and co-workers developed new SOFCs systems that
exhibits superior performance at 300-600 oC temperature range and called new generation or low
temperature (LT, 300-600 oC) SOFCs. The LTSOFCs at 300-600 oC are more suitable for direct
operations of methanol and ethanol since thermal cracking of these fuels to H2+CO occurs at this
temperature range.
Most of the work cited above concentrated on the new catalyst for anode for better cracking
liquid fuels and electrochemical reaction of H2, CO fuel. However, it is also a key to have efficient
cathode materiel for higher fuel cell performance. Jiang and Virkar [2] showed that specifically at low
temperature the main problem, which limits the fuel cell performance, is the slow reaction at cathode.
Therefore the aim of this work is to develop various cathode materials, which are more important to
realize the direct methanol, and ethanol fuelled LTSOFCs. Among these cathode materials some of them
are single phase oxide, e.g. commonly used perovskite oxide cathodes for regular SOFCs, some of them
are in two-phase composite structures that have demonstrated even better fuel cell performances. These
new cathodes used for methanol and ethanol fuelled LTSOFCs have not been reported. Three categories
of cathode are investigated: I) BSCF perovskite oxide; ii) LFN (LaFeO-based oxides, e.g. LaFe0.8Ni0.2O3)
perovskite oxides; iii) Bi- or Tri- phase metal oxides with or without lithiation.
Experimental Procedures
In all LTSOFC devices, we used the CBC or ceria-salt-composite electrolytes, for example, samarium
doped ceria (SDC) and carbonate composites. These CBC electrolytes possess superionic conduction [8,
11] demonstrating promising SOFC performances at low temperatures (300-600 oC). The typical SDCcarbonate composite electrolytes were prepared in two steps [8]. The first step involves the SDC
preparation. the SDC was prepared by the solution route with coprecipitation. Raw chemicals were used
3
as follows: cerium nitrate hexahydrate (Supplied by Sigma-Aldrich), gadolinium(III) nitrate hexahydrate
and samarium(III) nitrate hexahydrate (Aldrich). These chemicals were prepared as 1 M solutions. Then
the gadolinium(III) or samarium(III) nitrate hexahydrate solution was mixed with the cerium nitrate
hexahydrate solution according to the desired molar ratios. An appropriate amount of oxalate acid
solution (2M) was added to prepare the SCO (samarium doped ceria) precursor in the oxalate state. The
precipitate was rinsed several times in deionized water, followed by ethanol washing for several times in
order to remove water from the particle surfaces. The obtained precipitates were dried in an oven at
100C over night and then ground in a mortar. The resulting powder was sintered at 700 for 2 hours. The
resulting samples are SDC.
In the second step, the SDC-carbonate composite preparations were completed in following
procedures: i) by mixing the SDC and Li-NaCO3 (Li: Na = 2:1 molar ratio) powders in 80 SDC;20
LiNaCO3 or 90SDC:10LiNaCO3 in weight ratio. ii) The mixtures were ground, then sintered at 650C
for 0.5 hours and iii) finally ground for SDC-carbonate composite electrolytes.
Copper and its alloys have been widely used for catalysts to reform methanol and ethanol to produce
hydrogen [5,6,12,13]. We employed a range of the copper-based binary systems, e.g. Copper-nickel,
cooper-zinc, copper-tin etc. We observed that carbonate with active surface or NTC (nanotube carbon)
added to prepare the composite anode can even enhance the cell performances. Cu-Ni and Cu-Ni-C
composite anodes were prepared in following procedures as reported in ref. 1. The typical procedure is:
Activated carbons (AC)-supported CuO, NiO materials, AC-M, were synthesized employing coimpregnating and sintering processes. AC with 1200m2/g surface area (determined with multipoint BET
method) was ground thoroughly, and then treated with alkali and acid separately to remove impurities.
Appropriate Cu(NO3)2●3H2O(A.R.), Ni(NO3)2●6H2O (A.R.) (where A.R. is analytically pure reagent)
and pre-treated AC were dissolved in distilled water, after impregnating and drying, the composite was
then sintered at 300-400ºC in N2 atmosphere for 1 hr to form AC-M catalyst.
The composite anode materials were prepared by mixing AC-M and electrolyte, ceria-carbonate
composite (CCC) in a volume ratio 1:1. These materials were mixed and distributed uniformly, and then
were sintered at 650-700ºC in N2 for 1 hr. The sample was cooled to room temperature and ground
thoroughly for use. The composite anode materials AC-M(metal)-CCC possessed unique microstructure
and interfacial phase between the CCC and activated carbons [1].
In addition to above mentioned anode materials, we prepared various cathode materials which are
discussed individually below to construct the LTSOFC devices to measure the fuel cell performances
operated by different fuels, methanol, ethanol and hydrogen in some cases for comparison.
4
The fuel cell was constructed by using the cathode, CCC electrolyte, anode composite directly in
a hot co-pressed under 25-100 MPa into cylindrical pellets in one step. The cell size was normally 20
mm in diameter and 1 mm in thickness, and the active electrode area was about 2 cm2. In some cases, 12
mm diameter cell with the active electrode area of about 0.64 cm2 was also used for comparison. The
dense electrolyte was sandwiched between the composite anode and the cathodes. The fabricated fuel
cell pellets were heat-treated using a program-controlled furnace then placed between the fuel cell-clamp
with two gas chambers. Each of them has two alloy pipes (12 mm diameter). The anode and cathode
were faced outwards the pipes to be exposed to fuel and air, respectively. The two pipes were skillfully
designed to be a clamp that was convenient for the flows of fuels and air. The cell-clamp assembly was
placed into a tubular furnace for measurements. The fuels were methanol, ethanol and pure hydrogen for
comparison, and oxidant was air. The fuel flow was controlled at about 0.5-1.0 ml min-1 and air flow at
about 100 ml min-1 under 1 atm pressure.
Operation Principles of Alcohol Fueled SOFCs
The LTSOFC has a wide operating temperature range which fits perfectly required temperatures for thermal
cracking of hydrogen-carbon bond, leading to H2 and CO that can be directly used for fuel cell operation. Thus
operating LTSOFCs at high efficiencies and low expenses is possible without any reforming process. In 400 to
700ºC region, many liquid hydrocarbon fuels can be easily thermally decomposed, e.g. methanol:
CH3OH (g) 
2 H2 + CO
1
This process could theoretically deliver a product stream containing up to 67 vol% H2. The resulted H2 +
CO from process 1 can be directly operated in LTSOFCs.
In this case the H2 + CO is used as the fuel and air (O2) used as the oxidant, the following cell reactions take
place in LTSOFCs:
Anode:
H2 + O2-

H2O + 2e-
CO + O2-

O2 + 4e-

2
CO2 + 2e-
3
2O2-
4
Cathode:
5
Overall reaction:

H2 + CO + 2O2
H2O + CO2
5.
There may be another operation model existing for the direct liquid hydrocarbon fuelled LTSOFCs, i.e.
the direct oxidation of the liquid fuels, described as below.
Anode:
CnH2n+2 + (3n+1) O2-

n CO2 + (n+1) H2O + 2 (3n+1) e-
6
Cathode:
O2 + 4e-

2 O2-
7
The second operation model is much dependent on the catalyst electrodes used, and in general, it
has lower efficiency and activity compared to the first operation model, because commonly SOFC
electrode (anode) materials are very efficient for H2 + CO fuels as demonstrated before [10]. In this case,
methanol (CH3OH) could be effectively thermally decompose into CO + H2, followed by
electrochemical oxidation of CO+H2 during the FC operating to perform direct operation of the liquid
hydrocarbon fuel function and generate the electricity in the same time.
Results
Mainly three ranges of cathode materials prepared and tested for LTSOFC to be used in direct methanol
and ethanol operation. i) BSCF perovskite oxides; ii) LFN (LaFeO-based oxides, e.g. LaFe0.8Ni0.2O3)
perovskite oxides; iii) Bi- or Tri- phase metal oxides with or without lithiation. The performance of each
cathode materials is presented.
Performances of the proveskite oxidecathode materials
Perovskite oxides have some quite interesting properties, such as ionic conductivity, superconductivity,
magnetoresistance and ferroelectricity. LSFC (LaSrCoFeO) and BSFC (BaSrCoFeO) are very promising
cathode materials for SOFCs operated at IT (intermediate temperatures (600-800ºC), which are very
6
attractive in term of high conductivity and excellent oxygen transport and catalytic activity. The LSCF
and BSCF have been widely investigated for conventional YSZ (yttrium stabilized zirconia) and ion
doped ceria electrolytes. The BSCF was reported in Nature [14] as the excellent ITSOFC (IT: 500-800º
C) cathode materials with a demonstration of 1100 mWcm-2 at 600ºC, and 400mWcm-2 at 450ºC for the
cell with a 12 mm in diameter, showing excellent electrochemical properties for the ITSOFCs. Based on
this material excellent cathode properties reported for hydrogen operations, we prepared also BSCF
cathode used for methanol and ethanol fuelled LTSOFCs.
Figure 1 shows the performances for the CCC electrolyte LTSOFCs with 20 mm in diameter
operated by methanol and ethanol using the BSCF cathode material vs the Cu-Ni oxide-SDC anode,
respectively. The BSCF cathodes for methanol and ethanol operations produce about 200 mWcm2 and
180 mW/cm2, respectively at 500ºC. As reported the BSCF is the most promising cathode material for
LTSOFCs [14]. It may be expected that the results we obtained can be further improved higher. To
explore the BSCF used for our fuel cell system we further constructed the cell with same anode and
cathode material but operated by hydrogen, and also the cell was constructed in a smaller size, 12 mm in
diameter to explore the maximum performance potential to avoid the performance loss during the size
scale up. In general, it is true at larger size; there is always a performance loss during the size scaling up.
This cell operated by hydrogen has shown the maximum power density of 452.6mW/cm2 and 850
mW/cm2, and the short circuit currents of around 2000 mA/cm2 and 4000 mA/cm2 at 450 and 500ºC,
respectively (see Figure 2). These results are higher than those reported [14]. It proves that the BSCF is
also an excellent cathode for the CCC electrolyte in hydrogen fuel. Comparison of Figure 1 and Figure 2
shows that the cathode catalyst property of the BSCF to the methanol and ethanol fuels is somehow
limited against the hydrogen fuel.
In order to make improvement in future on the BSCF cathode LTSOFC performances, we have
conducted more studies on the BSCF preparation and structure properties.
Structural stability of the BSCF is concerned as an issue. BSCF is resulted from substitution of
Sr2+ partially by Ba2+ for the SrCo0.8Fe0.2O3-d(SCF). For SCF material, its perovskite phase structure is
thermodynamically stable only at higher temperature(>790) [15] and Ba2+ substituted BSCF does not
undergo such a phase transition. It is expected that the suppression of oxygen vacancy ordering and
phase transition result in technologically significant ion conductivities at lower temperatures suitable for
LTSOFC cathode applications with high performance due to its high conductivity.
The X-ray diffraction patterns of the powder BSCF calcined at different temperature were shown in
Fig.3. A cubic perovskite structure was formed after calcined at 800ºC, but its diffraction peaks were
7
very weak and broad, which indicated the powder BSCF was not crystallized completely. Some
unknown phases were found, which were ambiguously indexed Fe3O4, Co3O4 and SrO (or BaO). It is
difficult to index them accurately due to doping with multi-elements. At higher calcinations
temperatures, the peaks of unknown phase disappeared and the strength of the main peaks increased. The
single cubic perovskite structure was obtained after calcined at 1100 º C. When the calcinations
temperature rises to 1150ºC, the peaks of the powder turned to be stronger and sharper. These results
showed that the powder could be crystallized well after calcined at 1150 ºC. The lattice constant
a=0.3948 nm was obtain by an average value calculating with 2 for (211), (310), (311) peaks in the
XRD pattern. It was also consistent with that reported by Shao et al [14]. The morphology of the BSFC
powder from the SEM showed that the particle sizes of the powder made through the sol-gel method
were about 1~2μm, but some agglomerates were observed. The fine powders are favorable to contribute
to the improvement of the performance of the fuel cell.
Performance of LFN (LaNi1-xFexO3 (x=0.4-0.8) based oxides
The LFN-based oxides were studied in the literature as the cathode materials for the LTSOFCs [17]. The
LFN contain iron elements. The iron ions and its sites in the LFN structures may be expected to promote
the cathode catalyst functions. A single perovskite phase structure can be formed in whole composition
range with a sintering temperature at 900oC for 4h [16]. Our XRD analyses showed that when x0.5, the
structures are in the rhombohedral phase, which is the same as that of LaNiO3. When x>0.5, the
structures are in the orthorhombic phase, which is the same as that of LaFeO3. The lattice constants
increase with increasing the content of Fe, due to larger Fe ion radius than Ni one. It indicates that
substitution of Fe for Ni leads to not only increase of lattice parameters of the LNF, but also a phase
transformation from rhombohedral structure to orthorhombic structure. These results are consistent with
those reported previously by Chiba et al. [17].
The LNF materials showed good cathodic performances for hydrogen operation as reported
earlier [16]. We employed such cathode here for methanol operation. Figure 4 shows typical fuel cell
performances, I-V and I-P characteristics using the LaNi0.4Fe0.6O3 (x = 0.6) as the cathode which exhibits
the best cathodic performances at low temperatures (T 500 oC). It can be seen clearly from Fig. 4 that
the high OCV about 0.96 V for hydrogen, 0.9 V and 0.85 V for methanol and ethanol at 500 oC, are
8
respectively obtained, showing that such cathode performs high catalyst function as well. The maximum
power density of 220 mW/cm2 under the current density of 610 mA/cm2 are achieved for hydrogen, 200
mW/cm2 and 600 mA/cm2 for methanol, and 180 mW/cm2 and 580 mA/cm2for ethanol at 500 oC.
Performance of bi- or tri-phase metal oxides with or without lithiation, lithiated oxide cathodes
targeting for LTSOFCs
Extensive studies have been conducted to lithiated nickel oxide, i.e. LixNiO2+ (x = 0.05-1.0) cathode
materials for LTSOFCs. Such cathode materials have been reported to reach a power output of 800
mWcm-2 at 600ºC [9] for the ceria-based composite electrolyte fuel cells to hydrogen. Based on these
results, wide exploitation of new cathode materials based on lithiated metal oxides have been carried out
on the vanadium and copper oxide systems. Though the power output has not been reached even higher
compared to lithiated nickel oxides for hydrogen, these materials have showed an excellent catalyst
activity in direct operation of methanol and ethanol etc. liquid fuels. Moreover, it was also found that
these lithiated metal oxides can be also used as bi-functional electrode materials, i.e. the same materials
could be used for both anode and cathode materials in one fuel cell, so called symmetric electrode fuel
cells. These symmetric fuel cells can be operated reversibly, exploring a new fundamental study for
electrochemistry.
New developments have been achieved to further improve the fuel cell performances by using
the bi- or tri-phase oxides with or without lithiation. These oxides can be widely selected from transient
metals, such as copper, nickel, iron etc. and other metals, like Zn, Bi etc. Typical examples are such as
NiOx-CuOx, BiOx-CuOx, NiOx-ZnO, Cu(Ni)Ox-ZnO etc. The purpose of developing these bi- or tri
phase/metal oxide electrodes is to use them in the direct liquid fuels operational fuel cells. After
extensive tests, the best results have been so far achieved for such mixed oxide system. Figure 5 shows
the best direct alcohol (marketing available ethanol for automobile use) fuel cell performance using the
Cu(50 mol%)Ni(20 mol%)Ox-ZnO(30 mol%). Such fuel cell can deliver 300, 380 and near 500 mWcm-2
at 500, 550 and 580ºC, respectively.
Summary and Conclusions
9
Our efforts have explored a wide range of interesting cathode materials, such as prevoskite oxide,
BSCF and LNF-based oxides and many bi- or tri-metal oxides can be used as efficient cathode materials
for direct operation of methanol and ethanol for LTSOFCs. The best result has been achieved so far for
the tri-metal oxide (CuNiOxx-ZnO) cathode, the maximum power density output of 500 mW•cm-2 was
obtained at 580 oC for direct methanol operation, while the BSCF cathode is expected to have great
potential to improve the fuel cell performance. The LNF oxide materials have been proved also as
promising cathodes for direct methanol and ethanol fuelled LTSOFCs. All these good performances can
be achieved in combination of the AC-metal-SDC anode catalysts based on both ceria and AC-metal
catalyst functions while the internal reforming reaction of methanol or ethanol can effectively occur in
the anode chamber.
Acknowledgement
The Swedish Research Council (VR)/The Swedish National Agency for International Cooperation
Development (Sida) Asian partnership projects and Carl Tryggers Stiftelse for Vetenskap Forskning
(CTS) financially supports are highly appreciated. Partial financial support of Turkish National Science
Foundation (TUBITAK) for cooperation between KTH and Nigde University is acknowledged.
References
1
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2
Jiang Y. and Virkar AV. A high performance, anode supported solid oxide fuel cell
operating on direct alcohol. J. Electrochemical Society 2001; 148(7):A706-A709.
3
Saunders GJ., Preece J., Kendall K., Formulating liquid hydrocarbon fuels for SOFCs. J.
Power Sources 2004; 131:23-26.
4
Sasaki
K.,
Watanable
K.,
Teraoka
Y.
Direct-alcohol
SOFCs:current-voltage
characteristics and fuel gas compositions. J. Electrochemical Society 2004; 151
(7):A965-A970.
5
Brett DJL., Atkinson A., Cumming D., Ramirez-Cabrera E., Rudkin R., Brandon NP.
10
Methanol as a direct fuel in intermediate temperature (500-600 oC) solid oxide fuel cell
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6
Feng B.,Wang CY. and Zhu B., Catalyst and performance for direct methanol low temperature
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Zhu, B., Advantages of intermediate temperature SOFCs for tractionary applications. J.
Power Sources 2001; 92: 82-86.
8
Zhu, B., Functional ceria-salt composite materials for advanced ITSOFC applications. J.
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Zhu B.,Yang XT., Xu J., Zhu ZG., Ji SJ.,Sun MT.,Sun JC. Innovative low temperature
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copper-stabilized zirconia as an anode material for SOFCs Solid State Ionics 152– 153
(2002) 455– 462.
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16 Li S., Sun XL., Sun JC., and Zhu B.
A high functional cathode material
LaNi00.4Fe0.6O3 for low temperature solid oxide fuel cells, Electrochemical. and Solid
State Letters, 2 (2006) A86-87
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FIGURE CAPTIONS
11
Figure 1 Performance of BSFC and LSFC cathodes operated with methanol and ethanol
Figure 2. Typical I-V characteristics for LTSOFC using the BSCF cathode and CCC
electrolyte for hydrogen operation at 450 and 500ºC, respectively
Figure 3 The XRD patterns of samples at different calcinations temperatures
Figure 4 Fuel cell performances, I-V and I-P characteristics using the LaNi0.4Fe0.6O3 as the
cathode for various fuels at 500 oC.
Fig. 5. I-V characteristics for direct alcohol (marketing alcohol added by water in 3:1 ratio)
fuel cell at different temperatures.
12
,□ Methanol
, Ethanol
Figure 1 Performance of BSFC and LSFC cathodes operated with methanol and ethanol
1.0
1000
0.8
800
0.6
600
450C
0.4
400
450C
0.2
200
0.0
0
500
1000
1000
1500
1500
2
500C
power density (mw/cm )
voltage (v)
500C
2000
2000
0
2500
2500
2
current density (mA/cm )
Figure 2. Typical I-V characteristics for LTSOFC using the BSCF cathode and CCC electrolyte for
hydrogen operation at 450 and 500ºC, respectively
13
(110)
Ba0.5Sr0.5Co0.8Fe0.2O3-¦Ä
0
Co3O4
(311)
(310)
(220)
(210)
(211)
* SrO
(200)
(111)
(100)
Intensity (a.u.)
+ Fe3O4
1150¡æ
1100¡æ
0
0
1000¡æ
0
+
900¡æ
+
20
*
30
+
800¡æ
*
40
50
60
2¦È/
70
80
90
100
o
Figure 3 The XRD patterns of samples at different calcinations temperatures
0
200
400
600
250
1.0
Cell voltage (V)
150
0.6
100
0.4
H2
CH3OH
C2H5OH
0.2
50
-2
Power density (mWcm )
200
0.8
0.0
0
0
200
400
600
-2
Current density (mAcm )
Figure 4 Fuel cell performances, I-V and I-P characteristics using the LaNi0.4Fe0.6O3 as the
cathode for various fuels at 500 oC.
14
0
200
400
600
800
1000
1200
1400
1.0
P580
400
0.6
P550
300
P500
0.4
200
0.2
100
0.0
0
200
400
600
800
1000
1200
-2
V580
V550
V500
Power density (mWcm )
Cell voltage (V)
0.8
500
0
1400
-2
Current density (mAcm )
Fig. 5. I-V characteristics for direct alcohol (marketing alcohol added by water in 3:1 ratio)
fuel cell at different temperatures.
15