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Further development of solid oxide fuel cell (SOFC) oxygen electrodes can be achieved through improvements in oxygen electrode design by microstructure miniaturization alongside nanomaterial implementation. In this work, improved electrochemical performance of an La

This article presents electrolytic deposition of thin Rare Earth (RE) coatings on Crofer 22 APU stainless steel substrates for high temperature applications, such as interconnects in solid oxide cell stacks. The deposition of coatings based on yttrium-, gadolinium-, lanthanum-, and cerium nitrates is discussed. The high temperature corrosion properties of surface-modified steels were examined using thermogravimetry and electrical resistivity measurements. Coatings and oxide microstructures were examined by XRD and SEM of surfaces and cross-sections. The results showed that the use of the RE element oxide layers reduced the growth of oxide scale, as evidenced by lower weight gain. The layers based on Y- and Gd-oxides showed the best corrosion protection properties. The electrical measurements showed that the surface-modified samples had lower resistance than the uncoated sample.

In this work, the effect of the addition of graphene oxide (GO) to nickel-iron (NiFe) and cobalt-nickel-iron (CoNiFe) mixed oxide/hydroxide/(oxy)hydroxide catalysts on their morphological, structural, and oxygen evolution reaction (OER) catalytic activity is investigated. The catalysts are fabricated during two-step electrodeposition: the first step includes the deposition of GO flakes, which in the second step become reduced with simultaneous deposition of NiFe or CoNiFe. As a result, NiFe-GO and CoNiFe-GO are fabricated without any additives directly on the nickel foam substrate. A significant improvement of the OER activity was observed after combining NiFe with GO (OER overpotential η(10 mA·cm-2): 210 mV) compared to NiFe (η: 235 mV) and GO (η: 320 mV) alone. Different OER activity was observed for CoNiFe-GO. Here, the overall catalytic activity (η: 230 mV) increased compared to GO alone, however it was reduced in comparison with the CoNiFe (η: 224 mV). The latter was associated with the change in the morphology and structure of the catalysts. Further OER studies show that each of the catalysts has a specific role in influencing the process: the improvement in the OER by NiFe-GO results mainly from the structure of NiFe and the electroactive surface area of GO.

Development of environmentally friendly, high performing oxygen evolution reaction (OER) catalysts is an important research challenge. In this work, iron doped strontium titanates with a general formula SrTi1-xFexO3-δ (x = 0.35, 0.50, 0.70, 0.90, and 1.00) denoted as STFx, were synthesized via a solid state reaction technique and characterized in terms of oxygen evolution reaction electrocatalysis in an alkaline electrolyte (0.1 M KOH). The produced powders were characterized by a high specific surface area (>20 m2 g−1), beneficial for OER. The evaluation of specific activity indicated the following trend of increasing performance: STF35 < STF50 < STF70 < SFO < STF90. The lowest overpotential at 10 mAcm−2 GEO of 410 mV (350 mV at 25 μA cm−2OX) was achieved by STF90 with the corresponding Tafel slope of 60 mV dec−1. The two materials with the highest Fe content (i.e. STF90 and SFO) showed, however, poor chemical stability in alkaline solution demonstrated by the dissolution of Sr. Based on the good electrochemical performance (~460 mV at 10 mA cm−2GEO, ~405 mV at 25 μA cm−2OX) and chemical stability for at least 30 days (no Sr dissolution) of STF50, it can be considered an interesting, working at room temperature OER catalyst based on non-toxic and abundant elements.

The Crofer 22 H ferritic steel substrate was coated with an Mn1.45Co1.45Cu0.1O4 spinel by means of electrophoresis. After high-temperature oxidation under thermal cycling conditions, the physicochemical properties of the obtained system were evaluated. During 48-h cycles that involved heating the samples up to temperatures of either 750 or 800 °C, the oxidation kinetics of both coated and unmodified steel approximately obeyed the parabolic rate law. The unmodified steel was oxidized at a higher rate than the system consisting of the substrate and the coating. In its bulk form, the spinel consisted entirely of the cubic phase and it exhibited high electrical conductivity. The Mn1.45Co1.45Cu0.1O4 coating, on the other hand, was compact and consisted of two phases—the cubic and the tetragonal one—and it was characterized by good adhesion to the metallic substrate. After cyclic oxidation studies conducted for the two investigated temperatures (750 or 800 °C), the coating was determined to provide a considerable improvement in the electrical properties of the Crofer 22 H ferritic steel, as demonstrated by the area-specific resistance values measured for the steel/coating system. The evaporation rate of chromium measured for these samples likewise indicates that the coating is capable of acting as an effective barrier against the formation of volatile compounds of chromium. The Mn1.45Co1.45Cu0.1O4 spinel can therefore be considered a suitable material for a coating on the Crofer 22 H ferritic steel, with intermediate-temperature solid oxide electrolyzer cells as the target application.

In the study, the surface of the Crofer 22APU ferritic steel was modified with gadolinium oxide nanoparticles and a protective-conducting layer consisting of the MnCo2O4 spinel. This system was studied in the context of application in IT-SOFC interconnects. Four types of samples were studied: unmodified steel, steel coated with a manganese-cobalt spinel layer, steel modified with gadolinium oxide nanoparticles, and a system consisting of steel after both modifications. Steel samples with Gd2O3 nanoparticles were obtained via dip-coating, while the spinel coatings were deposited electrophoretically. All samples were oxidized for 1000 and 2260 h in air at 1073 K. Microstructural and oxidation kinetics studies revealed that gadolinium segregation at grain boundaries in the Cr2O3 scale between the steel and the spinel layer reduces the oxidation rate for the steel/coating system, thereby improving the adhesion of the scale to the substrate. The applied modification decreased the chromium evaporation rate and improved the electrical properties of the interconnect material.

Spinel oxides with the general formula Mn1.7Cu1.3-xFexO4 (x= 0, 0.1, 0.3, 0.5) were prepared and evaluated in this work for their properties at high temperatures. The effect of partially substituting Cu by Fe has not been studied so far for this group of materials and is thus evaluated in this work. Mn1.7Cu1.3-xFexO4 powders were synthesised by a soft chemistry process and studied in terms of crystallographic phase analysis, electrical conductivity, thermal expansion, and sinterability behaviour. The results show that the Fe content has a significant influence on the phase composition and the resulting properties. Characterisation of the dilatometry and conductivity coupled with XRD phase analysis across a wide temperature range allowed the relations between the materials properties and compositions to be observed. The results indicate that Mn1.7Cu0.8Fe0.5O4 is a promising material for use as a protective coating for interconnects in intermediate temperature Solid Oxide Fuel Cells.

Ce0.8Gd0.2O1.9 (CGO) barrier layers are required to mitigate the chemical reactions between Sr-containing oxygen electrode materials and Zr-based oxygen ion conductors in high-temperature solid oxide cells. Barrier layers produced by different methods were studied in this work. As a reference, a cell with no barrier layer was measured. The application of the powder-processed barrier layers, considerably increases the performance. For further comparison, thin and dense CGO layers were produced by a low-temperature spray pyrolysis process. Three different thicknesses were evaluated: ∼300 nm, ∼700 nm and ∼1500 nm. The best performance was found for the ∼700 nm thick CGO barrier layer. It showed low ohmic and polarisation resistances. The low thickness and high density of the CGO barrier layer were found to be the important factors. The cells with the ∼700 nm CGO barrier layers were also evaluated for their electrolysis performance as well as fuel cell durability.

This work evaluates the effects of the sintering temperature (800 °C, 900 °C, 1000 °C) of SrTi1-xFexO3-δ (x = 0.35, 0.5, 0.7) porous electrodes on their electrochemical performance as potential oxygen electrode materials of solid oxide cells. The materials were prepared by a solid-state reaction method and revealed the expected cubic perovskite structure. After milling, the powders were characterised by a sub-micrometre particle size with high sinter-activity. It was shown that the lowest area specific resistance was achieved after sintering SrTi0.65Fe0.35O3 electrodes at 1000 °C, and SrTi0.5Fe0.5O3 and SrTi0.30Fe0.70O3 electrodes at 800 °C, which can be considered to be a relatively low temperature. In general, EIS measurements showed that increasing the Fe content results in lowered electrode polarisation and a decrease of the series resistance. Even though the studied materials have much lower total conductivities than state-of-the-art electrode materials (e.g. (La,Sr)(Co,Fe)O3), the polarisation resistances obtained in this work can be considered low.

Fe-doped Mn1,5Co1,5O4 coatings on Crofer22APU were processed by an electrophoretic co-deposition method and the corrosion resistance was tested at 750 °C up to 2000 hours.The “in-situ” Fe-doping of the manganese cobalt spinel was achieved by electrophoretic co-deposition of Mn1,5Co1,5O4 and Fe2O3 powders followed by a two-step reactive sintering treatment. The effects on the coating properties of two different Fe-doping levels (5 and 10 wt.% respectively) and two different temperatures of the reducing treatment (900 and 1000 °C) are discussed. Samples with Fe-doped coatings demonstrated a lower parabolic oxidation rate and thinner oxide scale in comparison with both the undoped Mn1,5Co1,5O4 spinel coating and bare Crofer 22 APU. The best corrosion protection was achieved with the combined effect of Fe-doping and a higher temperature of the reducing step at 1000 °C.

This paper seeks to examine how the Mn–Co spinel interconnect coating microstructure can influence Cr contamination in an oxygen electrode of intermediate temperature solid oxide cells, at an operating temperature of 750 °C. A Mn–Co spinel coating is processed on Crofer 22 APU substrates by electrophoretic deposition, and subsequently sintered, following both the one-step and two-step sintering, in order to obtain significantly different densification levels. The electrochemical characterization is performed on anode-supported cells with an LSCF cathode. The cells were aged prior to the electrochemical characterization in contact with the spinel-coated Crofer 22 APU at 750 °C for 250 h. Current–voltage and impedance spectra of the cells were measured after the exposure with the interconnect. Post-mortem analysis of the interconnect and the cell was carried out, in order to assess the Cr retention capability of coatings with different microstructures.

In this work, nanocrystalline layers based on the Pr, Gd co-doped CeO2 were investigated. For the preparation of thin layers, low-temperature spray pyrolysis technique was used. Different stoichiometries of the layers were produced for comparison on polished sapphire substrates. The microstructure of the prepared thin layers was studied by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and x-ray diffractometry (XRD). The total electrical conductivity as a function of Gd or Pr dopant were determined by DC electrical measurements using the Van der Pauw method in air atmosphere. The oxygen electrode interface analysis confirm protective character of the diffusion barrier layer based on doped CeO2.

In this study, SUS430 alloy is evaluated for its high temperature corrosion properties as a possible material for interconnects of solid oxide fuel cells (SOFCs). Samples are coated with Mn-Co by commercial physical vapor deposition (PVD) process and oxidized in air for 1250 h at 800 °C. A dense cubic Mn-Co-Fe spinel layer is formed on the surface, showing great effect on corrosion reduction compared with the samples without coating. A corrosion rate constant of 1.22 × 10−14 g2 cm−4 s−1 is presented in this study for the coated samples, with an area specific resistance (ASR) of around 31 mΩ cm2. After the experiment, microstructures of the samples are analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM)/energy dispersive spectroscopy (EDS), which shows that the SUS430 alloy with Mn-Co coating can be considered as one of the low-cost material for the interconnects of SOFCs with good performance.

The 430L stainless steel powder with a mean particle size of 95 μm was studied to determine its high-temperature oxidation properties. Continuous thermogravimetric measurements were carried out for 100 h in air at temperatures in the range of 600–850 °C. Even though a considerable amount of Cr (up to ˜5 wt.% Cr) inside the grains was depleted – especially inside small grains – no breakaway oxidation was observed. This indicates that both the remaining Cr and the formed chromia scale remained protective with regard to the metallic core until the Cr concentration reached very low levels.

The aim of the presented study was to deposit protective-conducting Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinel coatings on the Crofer 22 H ferritic steel by means of electrophoresis and to evaluate their physicochemical properties after high-temperature oxidation under thermal cycling conditions. When the Crofer 22 H steel – whether uncoated or coated with the two spinels – was oxidized in 48-h cycles involving a temperature of either 750 or 800 °C, its oxidation kinetics approximately obeyed the parabolic rate law. The oxidation rate observed for uncoated steel was higher than that for the studied coating/steel systems. The Fe-doped spinel coating material improved the oxidation resistance of steel to a higher degree than the undoped spinel coating. The obtained bulk spinels exhibited a regular phase composition and high electrical conductivity, while the Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 coatings were dual-phase, compact, and exhibited good adhesion to the metallic substrate. The area-specific resistance values measured for the steel/coating systems indicate that the coatings significantly improve the electrical properties of the studied ferritic steel, especially at 800 °C. The conducted research confirmed the suitability of the Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinels as coatings on the Crofer 22 H ferritic steel to be applied in the production of interconnects used in intermediate-temperature SOFCs.

This work evaluates porous Sr0.86Ti0.65Fe0.35O3 (STF35) as a possible oxygen electrode material for Solid Oxide Cells. The powder synthesis was performed by solid state method. Characterization included DC electrical conductivity study of sintered bulk samples and impedance spectroscopy study of symmetrical electrodes deposited on gadolinium doped ceria substrates. Measurements were carried out in atmospheres with different pO2 levels: 0.1%–20% O2. Detailed equivalent circuit analysis was carried out in order to clarify the reaction pathway on porous electrode, which extends knowledge available for dense model electrodes. At 800 °C in 21% O2, the DC electrical conductivity of STF35 pellet was 0.6 S cm−1 and the polarization resistance of the electrode in the symmetrical cell was ∼100 mΩ cm2. Detailed impedance spectroscopy studies revealed that the largest contribution (∼80%) towards the polarization resistance is due to oxygen adsorption, which is limiting the oxygen reduction performance of the porous STF35 electrode. These results show the applicability of advanced impedance analysis methods (e.g. Distribution of Relaxation Times - DRT) for description of complex impedance electrode phenomena of porous electrodes.

In this work manganese cobalt spinel (MnCo2O4) coatings were deposited on steel substrates by spray pyrolysis at 390 °C. This is at much lower temperatures than previously reported (typically in excess of 900 °C). It was possible to produce coatings with well controlled thickness (2-5-10 μm). The as-deposited coatings were evaluated for their microstructural changes and electrical conductivity up to 800 °C. Results confirm the formation of a single phase spinel with high density and electrical conductivity. Based on the obtained results, it might be concluded that spray pyrolysis is a very promising method to develop protective coatings for steel substrates at low temperatures overcoming limitations of many other methods.

Ceramic coatings for metallic interconnects play a key role in limiting corrosion and chromium evaporation in solid oxide cells. This study presents the upscaling of the electrophoretic deposition (EPD) technique to process Mn-Co spinels on real-dimension Crofer 22 APU interconnects and the test in a SOFC stack. Area specific resistance of long-term test conducted for 5000 h at 850 °C demonstrated that two-steps sintering has a significant influence on the coating performance; an area specific resistance degradation rate of 0.5 mΩ cm2 kh−1 is recorded. Stack test, operated in fuel cell mode at 850 °C for 3000 h under application of 227 mA/cm², including 5 thermal cycles, demonstrated the effectiveness of the electrophoretically deposited Mn-Co spinel in limiting the oxide scale growth on the Crofer 22 APU. An advanced post mortem investigation showed the effectiveness of the EPD ceramic coating, even when considering different and complex surfaces of the Crofer 22 APU.

Some oxygen defective fluorites are non-Newnham electrostrictors, i.e., the electromechanical response does not depend on their dielectric properties. Here, we show gigantic electrostriction in nanocrystalline 25 mol% praseodymium doped ceria (PCO) bulk ceramics. The material was fabricated with a field-assisted spark plasma sintering (SPS) process from high-purity nanoscale PCO powders (< 20 nm). The SPS process consolidates the powders into a single-phase, highly dense material with a homogeneous microstructure and large grain boundary extension. Various thermally and chemically stable ionic defects are incorporated into the nanostructure, leading to superior electrical conductivity. The material shows an electrostriction strain coefficient (M33) of ~10−16 m2/V2 at frequencies below 100 Hz at room temperature. Such performance is comparable and even superior to Newnham's electrostrictors such as ferroelectric ceramics and polymeric actuators. Comparative analysis with polycrystals suggests that nanostructured PCO possesses electromechanically active nanodomains of Pr3+-VO pairs. Such results are unexpected and open novel insights on non-Newnham electrostrictors.

Metal-organic frames (MOFs) are regarded as excellent candidates for supercapacitors that have attracted much attention because of their diversity, adjustability and porosity. However, both poor structural stability in aqueous alkaline electrolytes and the low electrical conductivity of MOF materials constrain their practical implementation in supercapacitors. In this study, bimetallic CoNi-MOF were synthesized to enhance the electrical conductivity and electrochemical activity of nickel-based MOF, as well as the electrochemical performance of the CoNi-MOF in multiple alkaline electrolytes was investigated. The CoNi-MOF/active carbon device, as-fabricated with a 1 M KOH electrolyte, possesses a high energy density of 35 W h kg−1 with a power density of 1450 W kg−1, exhibiting outstanding cycling stability of 95% over 10,000 cycles. The design of MOF-based electrode materials and the optimization selection of electrolytes pave the way for constructing high-performance supercapacitors.

Solid oxide cells (SOCs) are electrochemical energy converters that can operate in two modes within one unit. In fuel cell mode (solid oxide fuel cell, SOFC), they directly convert chemical energy into electrical energy through a Knallgas reaction, which is the chemical reaction of oxygen and hydrogen forming water in a controlled manner. The opposite reaction, the splitting of water into hydrogen and oxygen, is the electrolysis reaction (solid oxide electrolysis cell, SOEC). The Knallgas reaction is exothermic, while the water splitting reaction is endothermic. SOCs today typically operate between 650°C and 900°C. Only three layers are required for the fundamental electrochemical reactions: an electrolyte and two electrodes—the anode (the positive pole) and the cathode (the negative pole). In this chapter, the fundamental reactions, the geometrical designs, the material requirements, and the status of SOFCs and SOECs are presented. In the following seven chapters, the most important components of an SOC are described and the chapter ends with a summary and outlook. The described components are: (i) oxygen-ion conductors (electrolyte), (ii) anode materials for SOFCs (cathode in SOEC mode), (iii) cathode materials for SOFCs (anode in SOEC mode), (iv) proton conductors and adjacent electrodes, (v) stack sealing materials, (vi) ceramic coatings for metal interconnects, and (vii) degradation effects limiting lifetime and performance.

Recent investigations have shown that highly oxygen defective cerium oxides generate non-classical electrostriction that is superior to lead-based ferroelectrics. In this work, we report the effect of field-assisted spark plasma sintering (SPS) on electro-chemo-mechanical properties of calcium doped ceria (CDC). Nanometric powders of Ca.10 nm are rapidly consolidated to form polycrystalline nanostructures with a high degree of crystalline disorder. Remarkably, the resultant material demonstrates a large electromechanical strain without a frequency-related relaxation effect. We conclude that electromechanical activity in CDC materials strictly depends on the Ca2+- V o ¨ interaction, while disorder at the crystalline boundaries has a minor effect.

We report a systematic microstructural and electrical characterization of iron doped Mn–Co spinel coatings processed by electrophoretic co-deposition of Mn1.5Co1.5O4 and Fe2O3 powders on Crofer 22 APU and AISI 441 steel substrates. Iron addition to Mn–Co spinel coating leads to a reduction of the area specific resistance on both substrates, after 3200 h at 750 °C. The Fe doped Mn–Co coating both leads to a thinner oxide scale and reduces the sub scale oxidation for the Crofer 22 APU substrate. Fe doped Mn–Co on AISI 441 shows both a thicker oxide scale and low area specific resistance values, likely due to a doping effect of the oxide scale by minor alloying elements. The different mechanisms by which iron doping of Mn–Co spinels can influence elemental interdiffusion at the steel-oxide scale-coating interfaces and relative contributions to the overall area specific resistance are evaluated by means of advanced electron microscopy. The promising results are further confirmed in a cell test, where the Fe doped MnCo coated interconnect does not induce any degradation of the oxygen electrode, proving its efficiency.

High-temperature reactions between glass–ceramic sealants and Fe-Cr alloy interconnects may lead to the formation of undesirable phases, and consequently degradation of solid oxide fuel/electrolyser devices. In this work, three different glass–ceramic sealants (Na-containing, Ba-containing, Sr-containing compositions) and Fe22Cr stainless steel powders (raw and pre-oxidised) are considered in order to test their chemical reactivity at 750 °C and 850 °C for 500 h in static air. The novelty of this approach is related to the use of powder mixtures instead of studying the reactivity on planar interfaces, which allows a better evaluation the materials’ reactivity. Oxidation tests indicate that the Sr-containing glass–ceramic/steel couple is the least reactive among the aged samples. For the Ba-containing samples, the formation of an undesirable phase of BaCrO4 is observed by diffractometry and photoelectron spectroscopy analyses. The present research explores, for the first time, the effects of exposing the high surface area of the alloy powder and glass–ceramic sealant interface, assessed by oxidation testing and microstructural analysis. The results show that by using mixed powders with large interface surface areas, degradation of the materials can be observed after relatively short times, allowing accelerated screening of the reactivity of materials, and thus their further development.

Interconnects used in Solid Oxide Cells stacks require protective coatings to lower their parabolic rate constant and block chromium evaporation (on the air side). In this work four different protective coatings on steel are evaluated for their high temperature corrosion resistance and electrical conductivity. A commercial electroplating process was used for the preparation of coatings with different Mn/Co ratios on Crofer 22 APU steel. Oxidation of samples was performed in air at 800°C for 1000 hours. Postmortem analysis of the coated samples was performed by scanning electron microscopy and x-ray diffractomettry. Based on the results, influence of the Co/Mn ratio on the resulting corrosion properties are discussed. Parabolic rate constant of the coated samples is the lowest for the MnCo sample, whereas electrical resistance is the lowest for the Co sample, which has a corrosion rate similar to the not-coated alloys.

This work describes a high temperature corrosion kinetics study of ~30% porous Fe22Cr alloys. The surface area of the alloy (~0.02 m2 g-1) has been determined by tomographic microscopy. The weight gain of the alloys was studied by isothermal thermogravimetry in the air for 100 hours at 700 - 900 °C. Breakaway oxidation was observed after oxidation at 850 °C (~100 hours) and 900 °C (~30 hours). The lifetime prediction shows the investigated porous alloy can be used for >3000 hours at temperatures

An adaptation of the Schwickerath crack initiation test (ISO 9693) was used to determine the bonding strength between an anode support and three different cathodes with a solid oxide fuel cell interconnect. Interfacial elemental characterization of the interfaces was carried out by SEM/EDS analysis on fracture surfaces to investigate the bonding mechanisms. SEM/EDS of fresh fractures were also performed to determine the cohesion/adhesion mechanism of bonding. Calculations of the residual stresses were determined by finite element simulation using ANSYS, based on thermo-mechanical properties of the materials obtained by measurement, calculation or literature.

Gadolinium doped ceria (Ce 0.8 Gd 0.2 O 2 − x -CGO) layer fabricated by spray pyrolysis is investigated as the diffusion barrier for solid oxide fuel cell. It is deposited between the La 0.6 Sr 0.4 FeO 3 − δ cathode and the yttria stabilized zirconia electrolyte to mitigate harmful interdiffusion of elements. The parameters of the fabrication process are linked to the measured area specific resistances of the symmetrical cells and the efficiency of the fuel cells. Results show, that application of 800 nm thick barrier effectively hinder negative reactions, while 400 nm thick layer is sufficient to prevent degradation of the Ohmic resistance.

The paper presents recent advances in Poland in the field of high temperature fuel cells. The achievements in the materials development, manufacturing of advanced cells, new fabrication techniques, modified electrodes and electrolytes and applications are presented. The work of the Polish teams active in the field of solid oxide fuel cells (SOFC) and molten carbonate fuel cell (MCFC) is presented and discussed. The review is oriented towards presenting key achievements in the technology at the scale from microstructure up to a complete power system based on electrochemical fuel oxidation. National efforts are covering wide range of aspects both in the fundamental research and the applied research. The review present the areas of (i) novel materials for SOFC including ZrO2-based electrolytes, CeO2-based electrolytes, Bi2O3 based electrolytes and proton conducting electrolytes, (ii) cathode materials including thermal shock resistant composite cathode material and silver-containing composites, (iii) anode materials, (iv) metallic interconnects for SOFC, (v) novel fabrication techniques, (vi) pilot scale SOFC, including electrolyte supported SOFC (ES-SOFC) and anode supported SOFC (AS-SOFC), (vii) metallic supported SOFC (MS-SOFC), (viii) direct carbon SOFC (DC-SOFC), (ix) selected application of SOFC, (x) advances in MCFC and their applications, (xi) advances in numerical methods for simulation and optimization of electrochemical systems.