Advances In Fuel Cell Technology Research Articles

Oxygen vacancy-regulated atomic dispersed Au on CeFeOx for preferential oxidation of CO in H2-rich stream

CO preferential oxidation in H2-rich stream (CO-PROX) is a critical reaction for H2 purification in emerging hydrogen economy including advanced fuel cell technology. Au-based catalysts are viewed as some of the most promising catalysts but achieving high catalytic efficiency and selectivity is still challenging. Defect engineering is deemed as a powerful strategy to improve the intrinsic catalytic activity. Herein, CeFeOx-supported Au catalysts with controllable oxygen vacancy (Ov) concentrations were obtained and applied to CO-PROX. The results of characterizations showed that the Ovs were preferentially generated in conjunction with Au single atoms (SAs) rather than nanoparticles (NPs), which further modulated the surface electronic properties via surplus electrons in Ovs and enhanced the interfical interaction between Ovs and Au SAs. The CO-PROX results indicated that the reduced Au SA catalyst (Au1/CeFeOx-R) with the highest Ov concentration completely converted CO at temperature of 80 °C with relatively low reactivity towards H2 oxidation. The remarkable catalytic activity and selectivity were attributed to the modified electronic properties by Ovs that played a bridging role in electron transfer and accelerated reaction process, as well as the coupling effect of Ovs and Au SAs that enhanced the dissociative adsorption of O2 and the adsorption-oxidation of CO, resulting in a reduced reaction energy barrier and making CO oxidation more favorable than H2 oxidation. This research opens up an alternative strategy to simultaneously stabilize and activate single-atom catalysts.

Oxygen vacancy-enriched NiCo2O4 spinels/N-doped carbon nanotubes-graphene composites for the ethylene glycol electro-oxidation

The efficient electro-oxidation of alcohol fuels on non-platinum group metals (non-PGMs) is a crucial challenge in advanced fuel cell technology. This study presents a novel approach, focusing on systematically designing highly efficient composites through strategic interface engineering. The method harnesses the intrinsic potential of oxygen vacancies (Ov) in the NiCo2O4 spinel, while synergistically incorporating nitrogen heteroatoms into multi-walled carbon nanotubes mixed with graphene (N-CNTG). Ethylene glycol (EG) was employed as defect promoter at 0, 33, 66 and 100 % v/v EG. Micrographs showed that nanobars were the predominant morphology at 0 % v/v EG, and this shape shifted to nanometric hemispheres with the shift to EG. X-ray photoelectron spectroscopy (XPS) showed that the Ov increased from 23 % to 36 % shifting from 0 to 100 % v/v EG. Comparative electrocatalytic studies showed the remarkable performance of the engineered composites compared to Vulcan carbon (C), a standard support. The best onset potential (1.08 V) was found on NiCo2O4 EG33/N-CNTG. The onset potential was 330 mV higher to that of a gold nanomaterial, but the peak potential difference was only 140 mV. This was associated with the improvement of the electronic structure as revealed by chemical calculations, changing adsorption energies, apparent activation energies and resistances to charge transfer. These findings highlight the potential of interface engineering in achieving non-PGMs electrocatalysts.

Bismuth-Nanoparticles-Embedded Porous Carbon Derived from Seed Husks as High-Performance for Anode Energy Electrode.

In energy application technology, the anode part of the electrode is typically composed of carbon-coated materials that exhibit excellent electrochemical performance. The carbon-coated electrodes facilitate electrochemical reactions involving the fuel and the oxidant. Energy electrodes are used in stationary power plants to generate electricity for the grid. These large-scale installations are known as distributed generation systems and contribute to grid stability and reliability. Understanding the practical applications of energy materials remains a significant hurdle in the way of commercialization. An anode electrode has one key limitation, specifically with alloy-type candidates, as they tend to exhibit rapid capacity degradation during cycling due to volume expansion. Herein, biomass-derived carbon from sunflowers (seeds husks) via pyrolysis and then bismuth nanoparticles are treated with carbon via a simple wet-chemical method. The electrode Bi@C offers several structural advantages, such as high capacity, good cycling stability, and exceptional capability at the current rate of 500 mA g-1, delivering a capacity of 731.8 mAh g-1 for 200 cycles. The biomass-derived carbon coating protects the bismuth nanoparticles and contributes to enhanced electronic conductivity. Additionally, we anticipate the use of low-cost biomass with hybrid composition has the potential to foster environment-friendly practices in the development of next-generation advanced fuel cell technology.

Assessment of hydrogen gas turbine-fuel cell powerplant for rotorcraft

Conventional turboshaft engines are high power density movers suffering from low efficiency at part power operation and producing significant emissions. This paper presents a design exploration and feasibility assessment of a hybrid hydrogen-fueled powerplant for Urban Air Mobility (UAM) rotorcraft. A multi-disciplinary approach is devised comprising models for rotorcraft performance, tank and subsystems sizing and engine performance. The respective trade-offs between payload-range and mission level performance are quantified for kerosene-fueled and hybrid hydrogen tilt-rotor variants. The effects of gas turbine scaling and fuel cell pressurization are evaluated for different hybridization degrees. Gas turbine scaling with hybridization (towards the fuel cell) results in up to 21% benefit in energy consumption relative to the non-scaled case with the benefits being more pronounced at high hybridization degrees. Pressurizing the fuel cell has shown significant potential as cell efficiency can increase up to 10% when pressurized to 6 bar which translates to a 6% increase in overall efficiency. The results indicate that current fuel cells (1 kW/kg) combined with current hydrogen tank technology severely limit the payload-range capability of the tilt-rotor. However, for advanced fuel cell technology (2.5 kW/kg) and low ranges, hybrid powerplant show the potential to reduce energy consumption and reduce emissions footprint.

Heteroatom-Doped Carbon Supports with Enhanced Corrosion Resistance in Polymer Electrolyte Membrane Fuel Cells

Polymer Electrolyte Membrane Fuel Cells (PEMFC) are currently considered the most advanced fuel cell technology. However, the industrial implementation of PEMFCs is strongly hindered by deficient durability, especially that of the carbonaceous materials commonly used to support the platinum-based catalyst nanoparticles, which are prone to electrochemical corrosion at the cathode, resulting in a serious performance loss of the entire cell. In the attempt to overcome this issue, many research groups have tried to introduce heteroatoms (N, S, B, P) into the carbon lattice, thus trying to make the electrode corrosion-resistant. Newly developed heteroatom-doped carbons were subjected to corrosion tests in half-cell and single-cell systems to evaluate their stability. This paper reviews the recent studies devoted to corrosion research of heteroatom-doped carbon supports for Pt-based catalysts in PEMFCs. In particular, an overview on N, B, and S dopants and their effects on carbon corrosion is provided.

Mechanical Interlocking Enhances the Electrocatalytic Oxygen Reduction Activity and Selectivity of Molecular Copper Complexes.

Efficient O2 reduction reaction (ORR) for selective H2O generation enables advanced fuel cell technology. Nonprecious metal catalysts are viable and attractive alternatives to state-of-the-art Pt-based materials that are expensive. Cu complexes inspired by Cu-containing O2 reduction enzymes in nature are yet to reach their desired ORR catalytic performance. Here, the concept of mechanical interlocking is introduced to the ligand architecture to enforce dynamic spatial restriction on the Cu coordination site. Interlocked catenane ligands could govern O2 binding mode, promote electron transfer, and facilitate product elimination. Our results show that ligand interlocking as a catenane steers the ORR selectivity to H2O as the major product via the 4e- pathway, rivaling the selectivity of Pt, and boosts the onset potential by 130 mV, the mass activity by 1.8 times, and the turnover frequency by 1.5 fold as compared to the noninterlocked counterpart. Our Cu catenane complex represents one of the first examples to take advantage of mechanical interlocking to afford electrocatalysts with enhanced activity and selectivity. The mechanistic insights gained through this integrated experimental and theoretical study are envisioned to be valuable not just to the area of ORR energy catalysis but also with broad implications on interlocked metal complexes that are of critical importance to the general fields in redox reactions involving proton-coupled electron transfer steps.

JM joins new European consortium to develop advanced fuel cell technology for heavy duty trucks

The effect of anisotropy of Ag nanoparticles on their electrocatalytic activity was investigated. By using increasing amounts of Cu salt etchant, we could obtain two AgNPs samples (S1 and S2) with different percentages of anisotropic nanoparticles. The third AgNPs sample was synthesized in the absence of any etchant and therefore resulted in the formation of only spherical nanoparticles. Investigation of ORR activity in an alkaline solution of these AgNPs samples showed that the S1/GC electrode gives rise to better reduction peak current, more positive reduction peak potential and stable electrocatalytic performance. Better results for the S1/GC electrode as compared to S2/GC electrode & S3/GC electrode can be owed to a higher percentage of anisotropic nanoparticles in S1 sample.

Comparative study and analysis between Solid Oxide Fuel Cells (SOFC) and Proton Exchange Membrane (PEM) fuel cell – A review

The ever increasing carbon foot print as a result of exhaustive utilization of non-renewable energy sources has caused an alarming change in environmental conditions. This review discusses recent advances in Fuel Cell Technology and draws a comparison between two prominent fuel cells namely, Proton Exchange Membrane (PEM) fuel cell and Solid Oxide Fuel Cell (SOFC). The review puts forward discrete advantages and disadvantages of the two mentioned fuel cells. A discussion is put forward in form of tabulated data consisting previous experimental studies of SOFC and significant findings of PEMFC technology. At the end a comprehensive conclusion has been drawn and also the future aspects are postulated.

Synthesis and conductivity behaviour of proton conducting (1−x)Ba0.6Sr0.4Ce0.75Zr0.10Y0.15O3−δ‐xGDC (x=0, 0.2, 0.5) composite electrolytes

AbstractAn attempt has been made here to synthesize (1−x)Ba0.6Sr0.4CZY‐xGDC (x=0, 0.2, 0.5) composite electrolytes and investigated their phase(s), X‐ray photo spectra (XPS) and conduction properties. All compositions possess dual phases (perovskite‐type as well as cubic fluorite structure) and show proton conduction in various atmospheres. Homogeneous formation and compatibility between phases have been confirmed from X‐ray diffraction analysis. Detailed X‐ray photoelectron spectroscopy (XPS) studies on the oxidation states of barium, strontium, gadolinium, cerium, zirconium, yttrium, and oxygen was performed. With increasing “x”, oxygen vacancy concentration increases as cerium ions in 4+ oxidation state decreases. The conduction behavior of composites depicts the protonic in nature and total activation energy lying in the range of 0.16‐0.24 eV. This study indicates that the conductivity increases with GDC content in composite electrolytes and highest conductivity is found for composite with x=0.5. These characteristics are useful to make (1−x)Ba0.6Sr0.4CZY‐xGDC composite electrolytes as promising candidate of central membrane for advanced fuel cell technology.

Pt Hollow Nanospheres As an Electrocatalyst for the Oxygen Reduction Reaction

H2-fed proton exchange membrane fuel cells (PEMFCs) represent the most advanced fuel cell technology and have a great deal of potential applications in low/zero-emission electric vehicles, distributed home power generators, and power sources for small and portable electronics. However, the commercialization of PEMFC technology has been greatly hindered by some challenges, mainly sluggish kinetics of the oxygen reduction reaction (ORR) at the cathode and the high cost of the noble metal Pt (1, 2). Alloying platinum with non-noble metals such as Co is an effective approach to improve the catalytic performance and reduce the usage of Pt. In addition, through transferring Pt nanoparticles (NPs) into a hollow nanostructure, electrocatalytic performance can be improved greatly due to its relatively lower density and higher surface area-to-volume ratio than its solid counterpart (i.e., NPs). In this work, Pt hollow nanospheres (HNSs) were fabricated through a replacement reaction of Co atoms by PtCl6 2- ions to reduce Pt usage and improve the catalytic activity towards the ORR. Carbon black Vulcan XC-72R (VC) was introduced into a solution prior to the addition of Co(II) and the formation of Co NPs and the replacement of Co by PtCl6 2-ions for a uniform dispersion of Co NPs and the Pt HNSs on the carbon support. Some Co atoms have alloyed Pt in the synthesis and exist in the Pt HNSs (3). The hollow mesoporous core in the Pt HNSs can be utilized as an electrolyte solution buffering reservoir to minimize the diffusion distance to the interior surface of the porous shell of Pt crystallites while the porous nanochannels (i.e., the micropores between the Pt crystallites) in the shell open to the mesoporous hollow core form fast mass transport networks providing more accessible sites for oxygen transfer. In addition, triple phase boundaries (i.e., gas-electrolyte-Pt NPs) can be developed more easily in the Pt HNS enabling individual Pt crystallites in the shell to be accessible to electrolyte ions and oxygen, and thus catalytically active. Furthermore, alloying Pt with Co might result in a significant lattice shrinking because of the change in Pt-Pt bond distance which also contributes to the improved electrocatalytic activity. In contrast, for the state-of-the-art Pt NPs/VC catalyst, the Pt NPs can agglomerate more easily to form larger particles, resulting in reduced active sites. Besides, the interior voids between Pt NPs may not be accessible to electrolyte ions and do not contribute to the ORR activity due to the lack of triple phase boundaries. As a result, the as-developed PtCo (20 wt%) HNS/VC catalyst outperforms significantly the state-of-the-art Pt(20 wt%)NP/VC catalyst.

Advances in Metal−Organic Ligand Systems for Polymer Electrolyte Membranes: A Review

AbstractThis review discusses the limitations and development of organic–inorganic polymer electrolyte membranes in the field of advanced fuel cell technology. The key achievements and challenges of hybrid membranes are extensively discussed, including the limitations of fluorinated and sulfonated membranes in terms of the durability of the energy system. The state‐of‐the‐art of advanced proton exchange membranes is high‐acidic intercalation for proton transfer through hydrogen bonding in metal–organic ligand polymer membranes. Metal–organic ligand polymer membranes are desirable for their unique feasibility of proton transfer through hydrogen bond in anhydrous environments. Organic acid moiety ligands functionalized with a metal or metal oxide have received significant attention because of their high proton conductivity and the stability of membranes. Metal–organic polymer membranes promise high proton conductivity owing to intramolecular proton transfer. Organic ligand polymers comprise mainly heterocyclic compounds, which provide spatial arrangements of acid moieties and periodic pattern morphologies due to hydrogen bonding. Metal oxide–organic ligand membranes are highly suitable for high temperature applications in terms of chemical stability. Methods of synthesis and the characteristics of metal–organic ligand polymer systems are described in this review. It is of interest to note that proton exchange membranes (PEM) could attain single active redox molecules through hydrogen bonding.

Pt Hollow Nanospheres As an Electrocatalyst for the Oxygen Reduction Reaction

H2-fed proton exchange membrane fuel cells (PEMFCs) represent the most advanced fuel cell technology and have a great deal of potential applications in low/zero-emission electric vehicles, distributed home power generators, and power sources for small and portable electronics. However, the commercialization of PEMFC technology has been greatly hindered by some challenges, mainly sluggish kinetics of the oxygen reduction reaction (ORR) at the cathode and the high cost of the noble metal Pt (1, 2). Alloying platinum with non-noble metals such as Co is an effective approach to improve the catalytic performance and reduce the usage of Pt. In addition, through transferring Pt nanoparticles (NPs) into a hollow nanostructure, electrocatalytic performance can be improved greatly due to its relatively lower density and higher surface area-to-volume ratio than its solid counterpart (i.e., NPs). In this work, Pt hollow nanospheres (HNSs) were fabricated through a replacement reaction of Co atoms by PtCl6 2- ions to reduce Pt usage and improve the catalytic activity towards the ORR. Carbon black Vulcan XC-72R (VC) was introduced into a solution prior to the addition of Co(II) and the formation of Co NPs and the replacement of Co by PtCl6 2-ions for a uniform dispersion of Co NPs and the Pt HNSs on the carbon support. Some Co atoms have alloyed Pt in the synthesis and exist in the Pt HNSs (3). The hollow mesoporous core in the Pt HNSs can be utilized as an electrolyte solution buffering reservoir to minimize the diffusion distance to the interior surface of the porous shell of Pt crystallites while the porous nanochannels (i.e., the micropores between the Pt crystallites) in the shell open to the mesoporous hollow core form fast mass transport networks providing more accessible sites for oxygen transfer. In addition, triple phase boundaries (i.e., gas-electrolyte-Pt NPs) can be developed more easily in the Pt HNS enabling individual Pt crystallites in the shell to be accessible to electrolyte ions and oxygen, and thus catalytically active. Furthermore, alloying Pt with Co might result in a significant lattice shrinking because of the change in Pt-Pt bond distance which also contributes to the improved electrocatalytic activity. In contrast, for the state-of-the-art Pt NPs/VC catalyst, the Pt NPs can agglomerate more easily to form larger particles, resulting in reduced active sites. Besides, the interior voids between Pt NPs may not be accessible to electrolyte ions and do not contribute to the ORR activity due to the lack of triple phase boundaries. As a result, the as-developed Pt(20 wt%) HNS/VC catalyst outperforms significantly the state-of-the-art Pt(20 wt%)NP/VC catalyst.

(Invited) Materials Challenges in Advanced Water Splitting Technologies

The US Department of Energy’s (DOE) Fuel Cell Technologies Office (FCTO) has made significant progress in hydrogen and fuel cell technology advancement and cost reduction. With the rollouts of fuel-cell vehicles by major automotive manufacturers underway, enabling technologies for the widespread production of affordable, renewable, low carbon footprint hydrogen becomes increasingly important. FCTO’s Hydrogen Production Program supports a broad range of H2 production pathways, ranging from nearer-term to longer term technologies. Advanced water splitting (AWS), including electrolysis, photoelectrochecmical and thermochemical routes, is one of the more versatile pathways and can play a significant role. A general overview of FCTO’s H2 Production Program with a focus on advanced water splitting technologies will be provided. Fundamental materials challenges remain which limit conversion efficiency and durability of AWS H2 production pathways, therefore limiting large-scale technoeconomic viability. Expensive materials are commonly required. Innovations are needed in the development of functional materials and interfaces which address the thermodynamic and kinetic limitations to performance and lifetime at the macro-, meso- and nano-scales. Catalytic advances, especially with respect to low- and non-platinum group metal (pgm) hydrogen and oxygen evolution catalyst materials in both acidic and basic environments, are needed for low temperature electrolysis operation. Examples of ongoing electrolysis and photoelectrochemical R&D will be discussed.

Fuel Flexible and Efficient Semionics Single Layer Fuel Cell

Fuel cells are traditionally based on a three-layer configuration - anode, electrolyte and cathode –leading to a complex structure, not least since the three layers have to be chemically stable and mutually compatible. Our new electrolyte-free, single layer fuel cell represents a radically new approach to fuel cell research and design. An advanced fuel flexible single layer/electrolyte free fuel cell with a functional nanocomposite was developed. Several different types of fuel, for example, gaseous (hydrogen and biogas) and liquid fuels (bio-ethanol and bio-methanol), were used in the experiments. Maximum power densities of 800, 300, 500, 400 mW cm-2 were achieved using hydrogen, bio-gas, bio-methanol, and bio-ethanol, respectively. These results show that single layer/electrolyte free fuel cell systems with functional nanocomposite offer significant advantages in reducing the operational and capital costs for the production of power and heat with a multi-fuel flexibility. This system might be the one of the promising solutions for sustainable energy development. This study is based on nanocomposites for advanced fuel cell technology (NANOCOFC) to develop functional nanocomposite materials for next generation marketable products. References B.Zhu, Rizwan Raza, Q.Liu, H.Qin, L.Fan, “Fuel cells based on the electrolyte and non-electrolyte separator” Energy and Environmental Sciences , 2011, 4 (8), 2986 - 2992.

Critical Metrics and Fundamental Materials Challenges for Renewable Hydrogen Production Technologies

ABSTRACTThe US Department of Energy’s (DOE) Fuel Cell Technologies Office has made significant progress in fuel cell technology advancement and cost reduction. Encouragingly, rollouts of fuel-cell vehicles by major automotive manufacturers are scheduled over the next several years. With these rollouts, enabling technologies for the widespread production of affordable renewable hydrogen becomes increasingly important. Near-term utilization of current reforming and electrolytic processes is necessary for early hydrogen markets, but transitioning to industrial-scale renewable hydrogen production remains essential to the longer term. Central to the long term vision is a portfolio of renewable hydrogen conversion processes, including, for example, the direct photoelectrochemical and thermochemical routes, as well as photo-assisted electrochemical routes. DOE utilizes technoeconomic analyses to assess the long-term viability of these emerging hydrogen production pathways and to help identify key materials- and system-level cost drivers. Sensitivity analysis from the technoeconomic studies will be discussed in connection with the metrics and fundamental materials properties that have direct impact on hydrogen cost. It is clear that innovations in macro-, meso- and nano-scale materials are all needed for pushing forward the state-of-the-art. These innovations, along with specific research and development pathways for advancing materials systems for the renewable hydrogen conversion technologies are discussed.

(Invited) Critical Assessment of Research and Development Needs in Solar to Hydrogen Production Technologies

The U.S. Department of Energy’s Fuel Cell Technologies Program (FCT) has made significant progress in fuel cell technology advancement and cost reduction, highlighted by reducing the cost of automotive fuel cells by more than 80% since 2002. Research and development of enabling technologies for the widespread production of affordable renewable hydrogen remains a challenge. In response, FCT worked with the federal Hydrogen and Fuel Cell Technical Advisory Committee to assemble an Expert Panel on Hydrogen Production, comprised of leading experts from industry, academia and national laboratories, to evaluate the current status and future prospects for viable hydrogen production technologies. Key emphases were on current reforming and electrolytic processes in near-term hydrogen markets and the need to transition to industrial-scale renewable hydrogen production for the longer term. Central to the long term vision are the solar-to-hydrogen conversion technologies, including the photoelectrochemical, biological, thermochemical and integrated solar-electrolysis routes.

A Conversation with Haldor Topsøe

Haldor Topsøe was born in Copenhagen, Denmark, in 1913. He studied chemical engineering at the Technical University of Denmark (DTU). In 1940, he founded the company Haldor Topsøe, which has become one of the most successful companies in the field of heterogeneous catalysis. The company develops and markets catalysts and processes for petroleum refining, air-pollution control, synthesis gas production, ammonia and methanol production and solid oxide fuel cells. The company Haldor Topsøe is also a leader in the production and state-of-the-art scientific characterization of new catalysts. Dr. Topsøe is currently the sole owner of the company. He has written numerous articles on ammonia synthesis, catalysis, and energy questions. He is the author of several books on economics. Dr. Topsøe has received numerous awards, including honorary doctorates from Aarhus University, DTU, and the Chalmers University in Sweden; the Gold Medal from the Royal Academy of Sciences; the Hoover Medal for his technical abilities and entrepreneurship; and the Grove Memorial Medal for Advances in Fuel Cell Technology. Topsøe is a member of the Danish and the Swedish Academies of Technical Sciences and of the U.S. National Academy of Engineering. The following interview was conducted on August 16, 2010. –Manos Mavrikakis

Nanocomposite electrode materials for low temperature solid oxide fuel cells using the ceria-carbonate composite electrolytes

Abstract Low temperature solid oxide fuel cell (LTSOFC, 300–600 °C) is one of the hot areas in recent fuel cell developments. In order to develop high performance LTSOFCs, compatible electrodes are highly demanded. We used NANOCOFC (nanocomposites for advanced fuel cell technology) approach to develop nanocomposite electrodes based on metal oxides Ni–Cu–Zn-oxide and samarium doped ceria (SDC). It was found that the materials consist of individual metal oxide and SDC phase, indicating the material as a composite with a homogenous distribution for all constituent components. Highly homogenous distribution of the particles enhanced the catalyst function for electrode applications in LTSOFC devices. We constructed the devices using the SDC-carbonate nanocomposite (NSDC) as the electrolyte and above as prepared composite as electrodes in a symmetrical configuration. We found that the prepared composite electrodes had good catalytic function for both H 2 and O 2 , to prove its anode and cathode functions. Based on the material properties, the LTSOFC devices have reached a power output more than 730 mW cm −2 at 550 °C.

Nanocomposites for Advanced Fuel Cell Technology

NANOCOFC (Nanocomposites for advanced fuel cell technology) is a research platform/network established based on the FP6 EC-China project www.nanocofc.org. This paper reviews major achievements on two-phase nanocomposites for advanced low temperature (300-600 degrees C) solid oxide fuel cells (SOFCs), where the ceria-salt and ceria-oxide composites are common. A typical functional nanocomposite structure is a core-shell type, in which the ceria forms a core and the salt or another oxide form the shell layer. Both of them are in the nano-scale and the functional components. The high resolution TEM analysis has proven a clear interface in the ceria-based two-phase nanocomposites. Such interface and interfacial function has resulted in superionic conductivity, above 0.1 S/cm at around 300 degrees C, being comparable to that of conventional SOFC YSZ at 1000 degrees C. Against conventional material design from the structure the advanced nanocomposites are designed by non-structure factors, i.e., the interfaces, and by creating interfacial functionalities between the two constituent phases. These new functional materials show indeed a breakthrough in the SOFC materials with great potential.

GDC - Y 2 O 3 Oxide Based Two Phase Nanocomposite Electrolyte

Oxide based two phase composite electrolyte (Ce0.9Gd0.1O2–Y2O3) was synthesized by coprecipitation method. The nanocomposite electrolyte showed the significant performance of power density 785 mW cm−2 and higher conductivities at relatively low temperature 550°C. Ionic conductivities were measured with ac impedance spectroscopy and four-probe dc method. The structural and morphological properties of the prepared electrolyte were investigated by scanning electron microscope (SEM). The thermal stability was determined with differential scanning calorimetry. The particle size that was calculated with Scherrer formula, 15–20 nm, is in a good agreement with the SEM and X- ray diffraction results. The purpose of this study is to introduce the functional nanocomposite materials for advanced fuel cell technology to meet the challenges of solid oxide fuel cell.