Novel high-temperature CO2 and H2O co-electrolysis superlattice composite oxygen electrode and preparation method thereof

Abstract

The invention belongs to the technical field of high-temperature CO2 and H2O co-electrolysis and solid oxide electrolysis pools, and relates to a novel high-temperature CO2 and H2O co-electrolysis superlattice composite oxygen electrode and a preparation method thereof. The composite oxygen electrode is structurally characterized in that a BSCF or LSCF substrate layer covers an electrolyte layer of a half-electrolytic-cell plate, and an active layer covers the substrate layer. BSCF or LSCF powder and M2-zSrzCoO4+theta powder are prepared by a low-temperature self-propagating method, the composite oxygen electrode substrate layer is prepared by a silk-screen printing method, a paste coating method or a wet spraying method, the composite oxygen electrode active layer is prepared by a soaking method, and the novel SOEC high-temperature CO2 and H2O co-electrolysis superlattice composite oxygen electrode can be prepared in a high-temperature sintering way. The composite oxygen electrode prepared by the method can remarkably improve the performance and operation stability of the solid oxide electrolytic cell and can prolong the service life of the electrolytic cell. The method is applicable to the field for preparing clean carbon hydrogen fuel in a high-temperature co-electrolysis way.

Description

technical field [0001] The invention belongs to CO 2 and H 2 O high temperature co-electrolysis and solid oxide electrolytic cell technical field, especially a kind of novel CO 2 and H 2 Superlattice composite oxygen electrode for high temperature co-electrolysis of O and its preparation method. Background technique [0002] The 200MW fourth-generation high-temperature gas-cooled reactor demonstration power plant project, a major medium- and long-term science and technology project in my country, has been launched. While actively developing nuclear power, using low-peak power to improve the economics of nuclear energy and expand new utilization of nuclear energy is currently a frontier topic in the field of nuclear energy research in various countries around the world. The principle of this technology is to develop a solid oxide electrolysis cell (Solid Oxide Electrolysis Cells, SOEC) that uses nuclear energy to flexibly drive high-temperature co-electrolysis of CO 2 an...

AI Technical Summary

Problems solved by technology

However, at lower temperatures (<700 °C), the slower oxygen evolution reaction kinetics of the oxygen electrode becomes the main obstacle limiting the performance of SOECs.

Co-based SOEC oxygen electrode (anode) materials (such as La 1-y Sr y co 0.2 Fe 0.8 o 3-δ , LSCF and Ba 1-x Sr x co 0.8 Fe 0.2 o 3-δ , BSCF) relative to the conventional La 0.8 Sr 0.2 MnO 3-δ (LSM) materials have better activity at medium and low temperatures; however, when they are used in SOEC oxygen electrodes, the high oxygen partial pressure accumulated on the interface between the electrolyte and the electrodes makes the oxygen electrodes detach from the electrolyte, resulting in the performance degradation of the electrolytic cell.

Therefore, even if they can run stably for thousands of hours in the battery mode, in the SOEC mode, they are exposed to serious delamination with the electrolyte, causing the electrolysis voltage to rise rapidly, so it is necessary to develop new types of Oxygen electrode materials and structures

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