Recent Developments for the Application of 3D Structured Material Nickel Foam and Graphene Foam in Direct Liquid Fuel Cells and Electrolyzers

Platinum and platinum-based catalysts are some of the most effective catalysts used in fuel cells. However, electrocatalysts used for direct liquid fuel cells (DLFCs) and electrolyzers are high cost and suffer from several other problems, thus hindering their commercialization as power sources to produce clean energy. Common issues in electrocatalysts are low stability and durability, slow kinetics, catalyst poisoning, high catalyst loading, high cost of the catalytic materials, poisoning of the electrocatalysts, and formation of intermediate products during electrochemical reactions. The use of catalyst supports can enhance the catalytic activity and stability of the power sources. Thus, nickel foam and graphene foam with 3D structures have advantages over other catalyst supports. This paper presents the application of nickel foam and graphene foam as catalyst supports that enhance the activities, selectivity, efficiency, specific surface area, and exposure of the active sites of DLFCs. Selected recent studies on the use of foam in electrolyzers are also presented.

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Numerical Investigation of PEMFC Short-Circuit Behaviour Using an Agglomerate Model Approach

Energies ◽

10.3390/en13164108 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4108

Author(s):

Carsten Cosse ◽

Marc Schumann ◽

Florian Grumm ◽

Daniel Becker ◽

Detlef Schulz

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Double Layer ◽

Short Circuit ◽

Clean Energy ◽

Gas Diffusion ◽

Operating Conditions ◽

Power Sources ◽

Peak Current ◽

Double Layer Capacity

With increasing interest in clean energy generation in the transportation sector, increasing attention has been given to polymer-electrolyte-membrane fuel cells as viable power sources. One issue, the widespread application of this technology faces, is the insufficient knowledge regarding the transient behaviour of fuel cells, for instance, following a short-circuit event. In this paper, an agglomerate model is presented and validated, which enables the transient simulation of short-circuit events to predict the resulting peak current and discharge of the double layer capacity. The model allows for the incorporation of detailed morphological and compositional information regarding all fuel cell components. This information is used to calculate the reaction rate, diffusional and convectional species transfer, and the momentum transport. It can be shown that the charge in the double layer capacitance of the fuel cell is key to predicting the peak current and its charge is dependent on the operating conditions of the fuel cell. Further, the effects of the magnitude of the double layer capacity, current rise time and stoichiometry on the dynamic behaviour of the fuel cell are investigated. It can be shown that the discharge of the double layer capacity proceeds from the membrane through the catalyst layer to the gas diffusion layer and that the stoichiometry of the gas supply does not significantly change the absolute peak value of the short-circuit current.

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In-Situ Preparation of Catalytic Diffusion Layers and Its Application in Direct Liquid Fuel Cells

ASME 2009 7th International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2009-85183 ◽

2009 ◽

Author(s):

Nie Luo ◽

Xiaoling Yang ◽

Kyu-Jung Kim ◽

James F. Stubbins ◽

George H. Miley ◽

...

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Power Density ◽

Liquid Fuel ◽

Electrochemical Corrosion ◽

Liquid Fuels ◽

Enabling Factors ◽

Power Sources ◽

Electro Deposition

Direct liquid fuel cells, such as the direct methanol fuel cell (DMFC) and borohydride fuel cell, may experience severe electrochemical corrosion problems due to the presence of conducting liquid fuels. This type of fuel cells has catalytic electrodes that are permeable to the liquid fuels. This permeability to liquids or solutions then opens up a possibility to the electrochemical improvement of catalytic electrodes once excessive corrosion has occurred. The in-situ electro-deposition or electroplating of the catalytic diffusion electrode is developed to first improve the performance and secondly mitigate the corrosion problem. The experimental details of such a technique are described in this paper. Direct liquid fuel cells thus treated typically have power density up to 40% higher, compared to fuel cells whose catalysts are prepared the traditional way. It is well known that power density is one of the enabling factors for portable power sources, for which the typical direct liquid fuel cells are designed. Therefore, the in-situ electroplating technique is expected to play an important role in the commercialization of fuel cell technology.

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Review on challenges of direct liquid fuel cells for portable application

World Journal of Engineering ◽

10.1260/1708-5284.12.6.591 ◽

2015 ◽

Vol 12 (6) ◽

pp. 591-606 ◽

Cited By ~ 6

Author(s):

Venkateswarlu Velisala ◽

G. Naga Srinivasulu ◽

B. Srinivasa Reddy ◽

K. Venkata Koteswara Rao

Keyword(s):

Fuel Cells ◽

Fuel Cell ◽

Energy Density ◽

Liquid Fuel ◽

Electronic Devices ◽

High Energy ◽

Pem Fuel Cells ◽

Green Energy ◽

High Energy Density ◽

Power Sources

Fuel cells technologies are the most promising green energy technologies for diverse applications. One of the fastest growing areas is the portable electronic applications where the power range is the order of 1–100 W. For most of the portable electronic devices, rechargeable battery is the major energy source. Due to limitations like limited capacity, requirement of external power for recharge have led many researchers to look for alternative power sources to power portable electronic devices. The high energy density of fuel cells makes them very attractive alternative to batteries for portable power applications. There are a variety of fuel cell technologies being considered to replace batteries in portable electronic equipment. Direct Liquid Fuel Cells (DLFCs) have attracted much attention due to their potential applications as a power source for portable electronic devices. The advantages of DLFCs over hydrogen fed PEM fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. Unlike batteries, fuel cells need not be recharged, merely refueled. This paper provides an overview on challenges of DLFCs (Direct Liquid Fuel Cells), like fuel crossover, cost, durability, water management, weight and size along with approaches being investigated to solve these challenges. Portable Fuel Cell Commercialization Targets for future and producers of portable fuel cells across the globe are also discussed in this paper.

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Rational Design of Spinel Oxide Nanocomposites with Tailored Electrochemical Oxygen Evolution and Reduction Reactions for ZincAir Batteries

Applied Sciences ◽

10.3390/app10093165 ◽

2020 ◽

Vol 10 (9) ◽

pp. 3165

Author(s):

Gnanaprakasam Janani ◽

Yujin Chae ◽

Subramani Surendran ◽

Yelyn Sim ◽

Woosung Park ◽

...

Keyword(s):

Oxygen Evolution ◽

Active Sites ◽

Rational Design ◽

Specific Capacity ◽

Chemical Properties ◽

Lithium Ion ◽

Power Sources ◽

Bifunctional Electrocatalyst ◽

Practical Applications ◽

Slow Kinetics

The unique physical and chemical properties of spinels have made them highly suitable electrocatalysts in oxygen evolution reaction and oxygen reduction reaction (OER & ORR). Zinc–air batteries (ZABs), which are safer and more cost-effective power sources than commercial lithium-ion batteries, hinge on ORR and OER. The slow kinetics of the air electrode reduce its high theoretical energy density and specific capacity, which limits its practical applications. Thus, tuning the performance of the electrocatalyst and cathode architecture is vital for improving the performance of ZABs, which calls for exploring spinel, a material that delivers improved performance. However, the structure–activity relationship of spinel is still unclear because there is a lack of extensive information about it. This study was performed to address the promising potential of spinel as the bifunctional electrocatalyst in ZABs based on an in-depth understanding of spinel structure and active sites at the atomic level.

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Catalytic Neutralization of Naphthenic Acid from Petroleum Crude Oil by Using Cerium Oxide Catalyst and 2- Methylimidazole in Polyethylene Glycol

Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) ◽

10.2174/2405520413999200819171315 ◽

2020 ◽

Vol 13 ◽

Author(s):

Norshahidatul Akmar Mohd Shohaimi ◽

Norfakhriah Jelani ◽

Ahmad Zamani Ab Halim ◽

Nor Hakimin Abdullah ◽

Nurasmat Mohd Shukri

Keyword(s):

Polyethylene Glycol ◽

Crude Oil ◽

Cerium Oxide ◽

Active Sites ◽

Naphthenic Acid ◽

Naphthenic Acids ◽

Catalyst Loading ◽

High Concentration ◽

Oil Refineries ◽

Al2o3 Catalyst

: The presence of relatively high naphthenic acid in crude oil may contribute to the major corrosion in oil pipelines and distillation units in crude oil refineries. Thus, high concentration Naphthenic Acids crude oil is considered tobe of low quality and is marketed at lower prices. In order to overcome this problem, neutralization method had been developed to reduce the TAN value in crude oil. In this study, crude oil from Petronas Penapisan Melaka was investigated. The parameters studied were reagent concentration, catalyst loading, calcination temperature and reusability of the potential catalyst. Basic chemical used were 2- methylimidazole in polyethylene glycol (PEG 600) with concentration 100, 500 and 1000 ppm. Cerium oxide-based catalysts supported onto alumina prepared with different calcination temperatures. The catalyst was characterized by using Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR) and Thermogravimetry Analysis-Differential Thermal Gravity (TGA-DTG) to study physical properties of the catalyst. The Ce/Al2O3 catalyst calcined at 1000°C was the best catalyst due to larger surface area formation which lead to increment of active sites thus will boost the catalytic activity. The result showed that the Ce/Al2O3 catalyst meet Petronas requirement as the TAN value reduced to 0.6 mgKOH/g from original TAN value of 4.22 mgKOH/g. The best reduction of TAN was achieved by using catalyst loading of 0.39% and reagent of 1000 ppm.

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Spinel of Nickel-Cobalt Oxide with Rod-Like Architecture as Electrocatalyst for Oxygen Evolution Reaction

Materials ◽

10.3390/ma13183918 ◽

2020 ◽

Vol 13 (18) ◽

pp. 3918

Author(s):

Anna Dymerska ◽

Wojciech Kukułka ◽

Marcin Biegun ◽

Ewa Mijowska

Keyword(s):

Cobalt Oxide ◽

Oxygen Evolution ◽

Active Sites ◽

Solvothermal Reaction ◽

Step Method ◽

One Pot ◽

Widespread Application ◽

Nickel Cobalt ◽

Slow Kinetics ◽

Nickel Cobalt Oxide

The renewable energy technologies require electrocatalysts for reactions, such as the oxygen and/or hydrogen evolution reaction (OER/HER). They are complex electrochemical reactions that take place through the direct transfer of electrons. However, mostly they have high over-potentials and slow kinetics, that is why they require electrocatalysts to lower the over-potential of the reactions and enhance the reaction rate. The commercially used catalysts (e.g., ruthenium nanoparticles—Ru, iridium nanoparticles—Ir, and their oxides: RuO2, IrO2, platinum—Pt) contain metals that have poor stability, and are not economically worthwhile for widespread application. Here, we propose the spinel structure of nickel-cobalt oxide (NiCo2O4) fabricated to serve as electrocatalyst for OER. These structures were obtained by a facile two-step method: (1) One-pot solvothermal reaction and subsequently (2) pyrolysis or carbonization, respectively. This material exhibits novel rod-like morphology formed by tiny spheres. The presence of transition metal particles such as Co and Ni due to their conductivity and electron configurations provides a great number of active sites, which brings superior electrochemical performance in oxygen evolution and good stability in long-term tests. Therefore, it is believed that we propose interesting low-cost material that can act as a super stable catalyst in OER.

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Investigation of Gas Diffusion Electrode Systems for the Electrochemical CO2 Conversion

Catalysts ◽

10.3390/catal11040482 ◽

2021 ◽

Vol 11 (4) ◽

pp. 482

Author(s):

Hilmar Guzmán ◽

Federica Zammillo ◽

Daniela Roldán ◽

Camilla Galletti ◽

Nunzio Russo ◽

...

Keyword(s):

Carbon Capture ◽

Active Sites ◽

Co2 Reduction ◽

Gas Diffusion ◽

Gas Diffusion Electrode ◽

Catalyst Loading ◽

Co2 Conversion ◽

Atmospheric Conditions ◽

Electrochemical Co2 Reduction ◽

Liquid Products

Electrochemical CO2 reduction is a promising carbon capture and utilisation technology. Herein, a continuous flow gas diffusion electrode (GDE)-cell configuration has been studied to convert CO2 via electrochemical reduction under atmospheric conditions. To this purpose, Cu-based electrocatalysts immobilised on a porous and conductive GDE have been tested. Many system variables have been evaluated to find the most promising conditions able to lead to increased production of CO2 reduction liquid products, specifically: applied potentials, catalyst loading, Nafion content, KHCO3 electrolyte concentration, and the presence of metal oxides, like ZnO or/and Al2O3. In particular, the CO productivity increased at the lowest Nafion content of 15%, leading to syngas with an H2/CO ratio of ~1. Meanwhile, at the highest Nafion content (45%), C2+ products formation has been increased, and the CO selectivity has been decreased by 80%. The reported results revealed that the liquid crossover through the GDE highly impacts CO2 diffusion to the catalyst active sites, thus reducing the CO2 conversion efficiency. Through mathematical modelling, it has been confirmed that the increase of the local pH, coupled to the electrode-wetting, promotes the formation of bicarbonate species that deactivate the catalysts surface, hindering the mechanisms for the C2+ liquid products generation. These results want to shine the spotlight on kinetics and transport limitations, shifting the focus from catalytic activity of materials to other involved factors.

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Metal-organic-framework derived hollow manganese nickel selenide spheres confined with nanosheets on nickel foam for hybrid supercapacitors

Dalton Transactions ◽

10.1039/d1dt01215k ◽

2021 ◽

Author(s):

Bahareh ameri ◽

Akbar Mohammadi Zardkhoshoui ◽

Saied Saeed Hosseiny Davarani

Keyword(s):

Active Sites ◽

Nickel Foam ◽

Metal Organic Framework ◽

High Surface ◽

Metal Organic Frameworks ◽

High Surface Area ◽

Supercapacitive Performance ◽

Hybrid Supercapacitors ◽

Porous Networks ◽

Metal Organic

Metal-organic frameworks (MOFs) derived nanoarchitectures have special features, such as high surface area (SA), abundant active sites, exclusive porous networks, and remarkable supercapacitive performance when compared to traditional nanoarchitectures. Herein,...

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Advances in the Applications of Graphene-Based Nanocomposites in Clean Energy Materials

Crystals ◽

10.3390/cryst11010047 ◽

2021 ◽

Vol 11 (1) ◽

pp. 47

Author(s):

Yiqiu Xiang ◽

Ling Xin ◽

Jiwei Hu ◽

Caifang Li ◽

Jimei Qi ◽

...

Keyword(s):

Solar Cells ◽

Fuel Cells ◽

Lithium Ion Batteries ◽

Electrode Materials ◽

Specific Capacity ◽

Lithium Ion ◽

Clean Energy ◽

Proton Exchange ◽

Energy Storage And Conversion ◽

Thermoelectric Conversion

Extensive use of fossil fuels can lead to energy depletion and serious environmental pollution. Therefore, it is necessary to solve these problems by developing clean energy. Graphene materials own the advantages of high electrocatalytic activity, high conductivity, excellent mechanical strength, strong flexibility, large specific surface area and light weight, thus giving the potential to store electric charge, ions or hydrogen. Graphene-based nanocomposites have become new research hotspots in the field of energy storage and conversion, such as in fuel cells, lithium-ion batteries, solar cells and thermoelectric conversion. Graphene as a catalyst carrier of hydrogen fuel cells has been further modified to obtain higher and more uniform metal dispersion, hence improving the electrocatalyst activity. Moreover, it can complement the network of electroactive materials to buffer the change of electrode volume and prevent the breakage and aggregation of electrode materials, and graphene oxide is also used as a cheap and sustainable proton exchange membrane. In lithium-ion batteries, substituting heteroatoms for carbon atoms in graphene composite electrodes can produce defects on the graphitized surface which have a good reversible specific capacity and increased energy and power densities. In solar cells, the performance of the interface and junction is enhanced by using a few layers of graphene-based composites and more electron-hole pairs are collected; therefore, the conversion efficiency is increased. Graphene has a high Seebeck coefficient, and therefore, it is a potential thermoelectric material. In this paper, we review the latest progress in the synthesis, characterization, evaluation and properties of graphene-based composites and their practical applications in fuel cells, lithium-ion batteries, solar cells and thermoelectric conversion.

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Direct-Hydrocarbon Proton-Conducting Solid Oxide Fuel Cells

Sustainability ◽

10.3390/su13094736 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4736

Author(s):

Fan Liu ◽

Chuancheng Duan

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Solid Oxide ◽

Sulfur Poisoning ◽

Oxide Fuel ◽

Power Sources ◽

Proton Conducting ◽

Conducting Oxides ◽

Operating Temperatures ◽

Ion Conducting

Solid oxide fuel cells (SOFCs) are promising and rugged solid-state power sources that can directly and electrochemically convert the chemical energy into electric power. Direct-hydrocarbon SOFCs eliminate the external reformers; thus, the system is significantly simplified and the capital cost is reduced. SOFCs comprise the cathode, electrolyte, and anode, of which the anode is of paramount importance as its catalytic activity and chemical stability are key to direct-hydrocarbon SOFCs. The conventional SOFC anode is composed of a Ni-based metallic phase that conducts electrons, and an oxygen-ion conducting oxide, such as yttria-stabilized zirconia (YSZ), which exhibits an ionic conductivity of 10−3–10−2 S cm−1 at 700 °C. Although YSZ-based SOFCs are being commercialized, YSZ-Ni anodes are still suffering from carbon deposition (coking) and sulfur poisoning, ensuing performance degradation. Furthermore, the high operating temperatures (>700 °C) also pose challenges to the system compatibility, leading to poor long-term durability. To reduce operating temperatures of SOFCs, intermediate-temperature proton-conducting SOFCs (P-SOFCs) are being developed as alternatives, which give rise to superior power densities, coking and sulfur tolerance, and durability. Due to these advances, there are growing efforts to implement proton-conducting oxides to improve durability of direct-hydrocarbon SOFCs. However, so far, there is no review article that focuses on direct-hydrocarbon P-SOFCs. This concise review aims to first introduce the fundamentals of direct-hydrocarbon P-SOFCs and unique surface properties of proton-conducting oxides, then summarize the most up-to-date achievements as well as current challenges of P-SOFCs. Finally, strategies to overcome those challenges are suggested to advance the development of direct-hydrocarbon SOFCs.

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