Cu-modified Ni foams as three-dimensional outer anodes for high-performance hybrid direct coal fuel cells

Bae

et al. 2021

ACS Appl. Nano Mater.

The use of non-platinum group metal (non-PGM) catalysts and liquid fuels is a good way to reduce the burden of commercialization and supply in fuel cells. However, it is very difficult to reach the power performance of commercial hydrogen–air fuel cells, 1.0–1.2 W cm–2, with only non-PGM catalysts. In this study, we synthesize a crustlike Cu@NiCo/C nanocomposite as an anode catalyst for a direct liquid hydrazine fuel cell via facile polyol reduction by injecting a Ni–Co solution into a Cu solution. By systematically investigating their electrocatalytic performance toward hydrazine oxidation in an alkaline solution, an appropriate proportion of three different non-PGM metals is carefully selected. For further investigation, we conduct various electrochemical analyses on Cu@NiCo/C nanoparticles, namely, X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and Tafel plot analyses, and confirm that the introduction of copper facilitates water adsorption and increases the conductivity of the catalyst. As a result, the application of Cu@NiCo/C as the anode catalyst of the hydrazine fuel cell can achieve a phenomenal power density of 1.08 W cm–2. Importantly, the crusty structure maintains its shape after harsh single-cell testing. This strategy provides not only further insights into alkaline liquid fuel cells using non-PGM catalysts but also the possibility for replacing hydrogen fuel cells.

Section: Resultsmentioning

confidence: 94%

Crusty-Structured Cu@NiCo Nanoparticles as Anode Catalysts in Alkaline Fuel Cells

Bae

et al. 2021

ACS Appl. Nano Mater.

“…15 Ni−Cu cermet anodes showed the enhanced resistance to carbon formation due to reduced adsorption energy of carbon for other hydrocarbon fuels. 18,19 The suppression of carbon deposition was also observed with Ni−Cu anodes, inhibiting anode deformation in methane-fueled protonic ceramic fuel cells. 20 Carbonate-superstructured solid fuel cells (CSSFCs), which possess ultrahigh conductivity of oxygen ions, are a new type of fuel cell with high efficiency, low cost, easy fabrication, high flexibility of fuels, and relatively low operating temperatures (∼500 °C).…”

Section: Introductionmentioning

confidence: 98%

“…Kim et al have examined Ni–Cu alloys with various compositions as anodes for the direct oxidation of methane in SOFCs at 800 °C, revealing a substantial reduction in coke formation on Ni–Cu alloys compared to pure Ni . Ni–Cu cermet anodes showed the enhanced resistance to carbon formation due to reduced adsorption energy of carbon for other hydrocarbon fuels. , The suppression of carbon deposition was also observed with Ni–Cu anodes, inhibiting anode deformation in methane-fueled protonic ceramic fuel cells …”

Section: Introductionmentioning

confidence: 99%

Unusual Promoting Effect of Ni–Cu Alloy Formation on Carbon Deposition in Carbonate-Superstructured Solid Fuel Cell with Methane Fuel

Su,

2024

Ind. Eng. Chem. Res.

Copper is usually exploited to modify nickel-based anodes for solid oxide fuel cells for inhibiting coke formation due to its low cost, higher electronic conductivity, and inert property to carbon formation. Herein, however, it was found that the formation of a Ni–Cu alloy promoted coke formation in carbonate-superstructured solid fuel cells (CSSFCs). Namely, a Ni–Cu alloy anode suffered remarkable carbon deposition that is approximately 2 orders of magnitude greater than that in either a Ni–Cu bimetallic anode or a pure Ni anode in a CSSFC with methane fuel. The Ni–Cu alloy anodes exhibit expanded lattice parameters and surface enrichment of copper, balancing the methane decomposition and carbon diffusion processes and leading to the formation of carbon filaments, thereby diminishing both the peak power densities and the overall stability of the CSSFC.

ACS Appl. Energy Mater.

“…Direct carbon solid oxide fuel cell (DC-SOFC) is recognized as a novel alternative clean coal utilization technology which is able to directly convert chemical energy into electrical energy . It has drawn numerous attention owing to the advantages of high efficiency, strong adaptability, no pollution, no noise, and simple assembly and also the launch of “dual-carbon strategic goal” (peak carbon dioxide emissions and carbon neutrality). − Thereinto, since there is no combustion process, the theoretical efficiency of completely electrochemical oxidation of carbon into CO 2 can reach or even be slightly higher than 100%. , …”

Section: Introductionmentioning

confidence: 99%

High-Performance La_0.9Sr_0.1Ga_0.8Mg_0.2O_3-δ Electrolyte-Based Direct Raw Brown Coal Fuel Cells

Chen,

Wu,

Hao

et al. 2023

Self Cite

The direct carbon solid oxide fuel cell (DC-SOFC) is a potential energy conversion device that cleanly and effectively utilizes various carbon resources to generate electric power through electrochemical conversion. Recently, DC-SOFCs utilizing real-world coal fuel have gained great momentum due to the “dual carbon strategic goals”. Here, we report high-performance La0.9Sr0.1Ga0.8Mg0.2O3‑δ (LSGM) electrolyte-supported DC-SOFCs, by integrating Ag–Gd0.1Ce0.9O2−δ (GDC) as symmetrical electrodes, which enable highly efficient utilization of raw brown coal as fuel. As a comparison, the performances of the conventional yttria-stabilized zirconia (YSZ) electrolyte supported-DC-SOFCs are also investigated. Fueled by raw brown coal, the LSGM-based cells can deliver a maximum power density of 367 mW cm–2 at 850 °C, which is distinctly superior than that of the YSZ-based cells (249 mW cm–2). In addition, stability tests reveal that under a discharge current of 0.15 A, the cell can achieve a discharge time of 4.38 h and a better fuel utilization of 14.8%, indicating that a large current discharge is more propitious for the LSGM-based DC-SOFCs fueled by raw brown coal to achieve higher fuel utilization. This study exhibits the enormous potential of LSGM as an electrolyte material for high-performance direct brown coal fuel cells and provides direction guidance for the optimization of discharge operation of DC-SOFCs directly utilizing brown coal in consideration of fuel utilization.