Dual 3D Ceramic Textile Electrodes: Fast Kinetics for Carbon Oxidation Reaction and Oxygen Reduction Reaction in Direct Carbon Fuel Cells at Reduced Temperatures

Abstract

Direct carbon fuel cells (DCFCs) are an efficient energy-conversion technology capable of generating electricity with carbon-dioxide-capture chemistry with solid carbon as fuels. The efficiency and performance of DCFCs depend on the kinetics of the carbon oxidation reactions (COR) and the oxygen reduction reactions (ORR), each occurring at anode and cathode, respectively. The limited active sites paired with reduced temperatures greatly decrease the efficiency of the electrochemical reactions. Ultraporous dual-3D ceramic textiles (dual-3DCT) are integrated into electrolyte-supported DCFCs to enhance charge and mass transfer at the electrodes. Improved COR at the anode is achieved by the synergy between the 3DCT NiO-Ce 0.8 Gd 0.2 O 1.95 (GDC) structure and optimal carbon fuel choice. In a comparative study, DCFCs using graphitic carbon (GC) as fuel show the best COR performance when compared to DCFCs utilizing alternative fuels such as carbon black (CB) and activated carbon (AC). The 3DCT Sm 0.5 Sr 0.5 CoO 3-δ -GDC (SSC-GDC) composite cathode shows electrochemical performance superior to that of the conventional screenprinted SSC-GDC. A peak power density of 392 mW cm −2 at 600 °C is obtained in a DCFC using the 3DCT-anode/electrolyte/3DCT-cathode configuration, an unprecedented value for any reported DCFC as of yet. This points toward promising applications of dual-3DCT electrodes for reduced-temperature DCFCs.

Regulation of Cathode Mass and Charge Transfer by Structural 3D Engineering for Protonic Ceramic Fuel Cell at 400 °C

“…Electrochemical Cell Fabrication: The 3DEC PBSCF cathode was fabricated by a template-derived method as shown in Figure S7, Supporting Information, which has been reported in the authors' previous work. [14] Stoichiometric amounts of high-purity Pr(NO 3 ) 3 · 6H 2 O (99.9%, Sigma Aldrich), Ba(NO 3 ) 2 · 6H 2 O (≥98%, Sigma Aldrich), Sr(NO 3 ) 2 (≥98%, Sigma Aldrich), Co(NO 3 ) 2 · 6H 2 O (≥98%, Sigma Aldrich), and Fe(NO 3 ) 3 · 9H 2 O (≥98%, Sigma Aldrich) were dissolved in DI water to form a homogeneous nitrate precursor solution. A piece of fabric textile purchased from Telio (Montreal, CA) was immersed into the precursor solution.…”

“…The utilization of carbon was 87.3% at 600 °C with a PPD of 0.392 W cm −2 . [14] In PCEC application, the electrolysis performance with the 3DCT steam electrode was 66.7% higher than that of the cell with a conventional screenprinted cathode at an applied voltage of 1.6 V at 500 °C. [13d] These studies provide new insights into the porous electrocatalyst with patterned shapes for reduced temperatures.…”

Review of molten carbonate-based direct carbon fuel cells

“…Recently, a dual 3D ceramic textile electrode was integrated into a GDC-carbonate composite electrolyte-supported DCFC, and thus, the TPB region was expanded [118]. Bian et al [81] developed a unique electrolyte-supported DCFC consisting of a GDC-(67 mol% Li 2 CO 3 -33 mol% Na 2 CO 3 ) electrolyte, a NiO-GDC anode and a Sm 0.5 Sr 0.5 CoO 3 -GDC cathode. It exhibited unprecedented cell performance at 600 °C, with a power output of 392 mW cm −2 when using graphitic fuel, due to the enhanced charge and mass transfer on the electrode below 600 °C [81].…”

“…Bian et al [81] developed a unique electrolyte-supported DCFC consisting of a GDC-(67 mol% Li 2 CO 3 -33 mol% Na 2 CO 3 ) electrolyte, a NiO-GDC anode and a Sm 0.5 Sr 0.5 CoO 3 -GDC cathode. It exhibited unprecedented cell performance at 600 °C, with a power output of 392 mW cm −2 when using graphitic fuel, due to the enhanced charge and mass transfer on the electrode below 600 °C [81]. High fuel utilization of 87.3% was also achieved, as the carbon fuel could quickly reach the…”

Atomic-Scale Design of High-Performance Pt-Based Electrocatalysts for Oxygen Reduction Reaction

“…Fuel cells, as clean and effective energy conversion devices that can directly convert the chemical energy of fuels and oxidants to electricity, are highly demanded to meet the urgent requirement of vehicles and exploitation of environmentally sustainable energies ( Chong et al, 2018 ; Pivovar, 2019 ). The oxidation reaction of fuels at the anode and the oxygen reduction reaction (ORR) at the cathode are the reactions involved in fuel cells ( Chen et al, 2019 ; Bian et al, 2020 ). Both anode and cathode reactions need catalysts to lower their electrochemical overpotential for high-voltage output ( Zhou et al, 2016 ; Jiao et al, 2021 ).…”