Preparation method of nanofiber composite cathode for intermediate temperature solid oxide fuel cell

Abstract

The invention relates to a preparation method of a nanofiber composite negative electrode of an intermediate-temperature solid oxide fuel cell, belonging to the technical field of energy materials. The preparation method comprises the following steps: firstly preparing a mixed spinning solution containing perovskite structured oxide components and oxygen ion conductor electrolyte components, spinning the mixed solution by virtue of an electrospinning technique to prepare composite fiber, drying and carrying out high-temperature sintering, so as to obtain nanofiber structured composite negative electrode. The diameter of the composite negative electrode fiber is 100-600 nanometers; nanofiber is formed by virtue of agglomeration of perovskite oxide components and electrolyte component nano-particles, wherein the mass percent of the perovskite oxide components is 45%-65%. Components in the nanofiber negative electrode are uniformly distributed, so that the transmission of ions and electrons is benefited; the activation area of electrochemical reaction and the interface of three-phase reaction are large, so that the oxygen reduction catalytic activity of the negative electrode is improved, and the polarization impedance of the negative electrode is reduced; furthermore, the preparation process is simple, the operation is easy, and the cost is low.

Description

technical field [0001] The invention belongs to the technical field of energy materials, and relates to a method for preparing a composite cathode with a nanofiber structure for a medium-temperature solid oxide fuel cell. Background technique [0002] The medium-temperature solid oxide fuel cell (SOFC) with an operating temperature in the range of 600-800 °C is an efficient, clean and green alternative energy source, and has potential application prospects in portable devices, automotive auxiliary power supplies, and decentralized power supply systems. A single SOFC cell is composed of a cathode, an electrolyte, and an anode, among which the cathode is the main factor limiting the output power of a medium-temperature SOFC. In order to improve the output power of SOFC, the cathode material must have high oxygen reduction catalytic activity, that is, low polarization resistance. Cobalt-based perovskite structure oxide is an ion-electronic mixed conductor material with high ca...

AI Technical Summary

Problems solved by technology

Using the solution impregnation-high-temperature sintering method described above, a composite cathode with high oxygen reduction catalytic activity can be obtained. However, in the preparation process, it is first necessary to synthesize powder and sinter the skeleton structure at high temperature, and because the amount of each impregnation solution is limited, multiple impregnations are required. -Drying-high-temperature sintering cycle operation can obtain the composite cathode with the required content. The whole composite cathode preparation process has many steps, complicated operation and long preparation cycle