Using density functional theory method, we have studied the oxygen dissociation in alkali molten carbonate at the B3LYP/6-31G(d) level. The calculated energies were then verified by MP4 and CCSD(T). A four-formula cluster (M2CO3)4, M = Li, Na, and K was used to describe the molten carbonate. It was found that the adsorption of oxygen to molten carbonate is of a chemical type and leads to the formation of CO5(2-) in MC, which was confirmed for the first time by DFT calculations. The energy barrier for its dissociation is calculated to be 197.9, 116.7, and 170.3 kJ/mol in the (M2CO3)4 cluster, M = Li, Na, and K, respectively. If the reaction of O2 + 2CO3(2-) → 2CO4(2-) is approximated as a one-step reaction, the activation energy is estimated to be 96.2, 15.1, and 68.6 kJ/mol, respectively. The reaction rate is first order to the pressure of oxygen. Surprisingly, the reaction of oxygen dissociation has the lowest energy barrier in sodium carbonate, which is consistent with the recent experimental findings. It is very clear that the molten carbonate salt has directly participated in the ORR process and plays an important role as a catalyst in the cathode of SOFCs. The oxygen reduction has been facilitated by MC and enhanced cell performance has been observed.
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http://dx.doi.org/10.1021/acs.jpca.5b06527 | DOI Listing |
Chem Commun (Camb)
January 2025
College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 215123 Jiangsu, China.
A two-dimensional (2D) amorphous iridium cobalt oxide (Am-IrCoO) was prepared using the molten salt method. The optimal catalyst shows a low overpotential of 230 mV at 10 mA cm in 0.5 M HSO.
View Article and Find Full Text PDFEnviron Res
January 2025
MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001, China.
In recent years, the accumulation of waste plastics and emergence plastic-derived pollutants such as microplastics have driven significantly the development and updating of waste plastic utilization technology. This study prepared the porous carbon (PC-1-KOH) material directly from polyethylene terephthalate (PET) in waste plastic bottles using KOH activation and molten salt strategy for efficient removal of antibiotic tetracycline (TC). The maximum removal efficiency of TC was 100.
View Article and Find Full Text PDFNanomaterials (Basel)
December 2024
Institute of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China.
The electrochemical conversion of CO into high value-added carbon materials by molten salt electrolysis offers a promising solution for reducing carbon dioxide emissions. This study focuses on investigating the influence of molten salt composition on the structure of CO direct electroreduction carbon products in chloride molten salt systems. Using CaO as a CO absorber, the adsorption principle of CO in LiCl-CaCl, LiCl-CaCl-NaCl and LiCl-CaCl-KCl molten salts was discussed, and the reasons for the different morphologies and structures of carbon products were analyzed, and it was found that the electrolytic efficiency of the whole process exceeded 85%.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Collaborative Innovation Center of Sustainable Energy Materials, School of Physical Science and Technology, Guangxi University, Guangxi Key Laboratory of Electrochemical Energy Materials, State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures, Nanning 530004, China. Electronic address:
Transition metal-nitrogen-carbon (MNC) based on 3d metal atoms as promising non-precious metal catalysts have been extensively exploited for oxygen reduction reaction (ORR), but MNC with 4f rare earth metals have been largely ignored, most likely due to their large atomic radii that are difficult to coordinate with N dopants using conventional precursors. Herein, atomically dispersed dysprosium-nitrogen-carbon (DyNC) nanosheets were developed via the pyrolysis of anitrogen-containing chelate compound of 2, 4, 6-Tri (2-pyridyl) 1, 3, 5-triazine (TPTZ) ligand with Dy under the assistance of molten NaCl. The as-synthesized DyNC features specific moieties of single Dy atom coordinated by N and O as active sites for ORR, displaying excellent performance.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Department of Chemical Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan.
Potassium metal batteries are emerging as a promising high-energy density storage solution, valued for their cost-effectiveness and low electrochemical potential. However, understanding the role of potassiphilic sites in nucleation and growth remains challenging. This study introduces a single-atom iron, coordinated by nitrogen atoms in a 3D hierarchical porous carbon fiber (Fe─N-PCF), which enhances ion and electron transport, improves nucleation and diffusion kinetics, and reduces energy barriers for potassium deposition.
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