Effect of Oxygen Partial Pressure on Solid Oxide Electrolysis Cells

doi:10.3866/PKU.WHXB201804171

CORC > 上海应用物理研究所 > 中国科学院上海应用物理研究所 > 中科院上海应用物理研究所2011-2017年

	Effect of Oxygen Partial Pressure on Solid Oxide Electrolysis Cells
	Hou, Q ; Guan, CZ ; Xiao, GP ; Wang, JQ ; Zhu, ZY
刊名	ACTA PHYSICO-CHIMICA SINICA
	2019
卷号	35 期号:3 页码:284—291
关键词	HIGH-TEMPERATURE ELECTROLYSIS HYDROGEN-PRODUCTION FUEL-CELLS STEAM ELECTROLYSIS AIR ELECTRODE PERFORMANCE POLARIZATION CATHODE MODEL EFFICIENCY
ISSN号	1000-6818
DOI	10.3866/PKU.WHXB201804171
文献子类	期刊论文
英文摘要	High-temperature (700-900 degrees C) steam electrolysis based on solid oxide electrolysis cells (SOECs) is valuable as an efficient and clean path for large-scale hydrogen production with nearly zero carbon emissions, compared with the traditional paths of steam methane reforming or coal gasification. The operation parameters, in particular the feeding gas composition and pressure, significantly affect the performance of the electrolysis cell. In this study, a computational fluid dynamics model of an SOEC is built to predict the electrochemical performance of the cell with different sweep gases on the oxygen electrode. Sweep gases with different oxygen partial pressures between 1.01 x 10(3) and 1.0 x 10(5) Pa are fed to the oxygen electrode of the cell, and the influence of the oxygen partial pressure on the chemical equilibrium and kinetic reactions of the SOECs is analyzed. It is shown that the rate of increase of the reversible potential is inversely proportional to the oxygen partial pressure. Regarding the overpotentials caused by the ohmic, activation, and concentration polarization, the results vary with the reversible potential. The Ohmic overpotential is constant under different operating conditions. The activation and concentration overpotentials at the hydrogen electrode are also steady over the entire oxygen partial pressure range. The oxygen partial pressure has the largest effect on the activation and concentration overpotentials on the oxygen electrode side, both of which decrease sharply with increasing oxygen partial pressure. Owing to the combined effects of the reversible potential and polarization overpotentials, the total electrolysis voltage is nonlinear. At low current density, the electrolysis cell shows better performance at low oxygen partial pressure, whereas the performance improves with increasing oxygen partial pressure at high current density. Thus, at low current density, the best sweep gas should be an oxygen-deficient gas such as nitrogen, CO2, or steam. Steam is the most promising because it is easy to separate the steam from the by-product oxygen in the tail gas, provided that the oxygen electrode is humidity-tolerant. However, at high current density, it is best to use pure oxygen as the sweep gas to reduce the electric energy consumption in the steam electrolysis process. The effects of the oxygen partial pressure on the power density and coefficient of performance of the SOEC are also discussed. At low current density, the electrical power demand is constant, and the efficiency decreases with growing oxygen partial pressure, whereas at high current density, the electrical power demand drops, and the efficiency increases.
语种	英语
内容类型	期刊论文
源URL	[http://ir.sinap.ac.cn/handle/331007/31571]
专题	上海应用物理研究所_中科院上海应用物理研究所2011-2017年
作者单位	1.Chinese Acad Sci, Shanghai Inst Appl Phys, Dept Molten Salt Chem & Engn, Shanghai 201800, Peoples R China; 2.Chinese Acad Sci, Key Lab Interfacial Phys & Technol, Shanghai 201800, Peoples R China; 3.Univ Chinese Acad Sci, Beijing 100049, Peoples R China
推荐引用方式 GB/T 7714	Hou, Q,Guan, CZ,Xiao, GP,et al. Effect of Oxygen Partial Pressure on Solid Oxide Electrolysis Cells[J]. ACTA PHYSICO-CHIMICA SINICA,2019,35(3):284—291.
APA	Hou, Q,Guan, CZ,Xiao, GP,Wang, JQ,&Zhu, ZY.(2019).Effect of Oxygen Partial Pressure on Solid Oxide Electrolysis Cells.ACTA PHYSICO-CHIMICA SINICA,35(3),284—291.
MLA	Hou, Q,et al."Effect of Oxygen Partial Pressure on Solid Oxide Electrolysis Cells".ACTA PHYSICO-CHIMICA SINICA 35.3(2019):284—291.