Low-temperature solid oxide fuel cell cathode in a core-shell nanofiber structure and preparation method thereof by electrospinning

Abstract

The invention relates to a low-temperature solid oxide fuel cell cathode in a core-shell nano fiber structure and an electrostatic spinning preparation method and belongs to the field of functional materials. The core-shell nano fiber structure cathode consists of a nano fiber core and a nano shell layer, wherein the fiber core and the shell layer respectively consist of a perovskite structure ion-electron mixed conductor component A and an oxygen ion conductor electrolyte component B or consist of opposite components; the core-shell nano fiber cathode is prepared in an electrostatic spinning manner, a component A before-spinning precursor solution and a component B before-spinning precursor solution are respectively prepared and then are respectively injected into an inner-layer spinning passage or an outer-layer spinning passage so as to carry out the spinning, and composite fibers are dried and sintered at a high temperature to obtain the core-shell nano fiber structure cathode material. By adopting the core-shell nano fiber structure, the oxygen reduction catalytic activity, anti-CO2 surface adsorption toxicity capacity and structural and performance stability of the low-temperature SOFC cathode are improved; moreover, the process is simple, and the cost is low.

Description

technical field [0001] The invention relates to a low-temperature solid oxide fuel cell cathode in a core-shell nanofiber structure and an electrospinning preparation method thereof, belonging to the field of functional materials. Background technique [0002] Solid Oxide Fuel Cell (SOFC) is a green alternative energy source with great application prospects. It is an important development direction in the SOFC field to reduce the working temperature from high temperature of 1000 ℃ to medium and low temperature range of 500-700 ℃. As the operating temperature of SOFC decreases, the oxygen reduction catalytic activity of the cathode decreases, and the polarization impedance increases rapidly, which becomes the key factor limiting the output power of SOFC at medium and low temperature; the decrease of operating temperature will also aggravate the CO on the surface of the cathode. 2 Adsorption poisoning leads to a further decline in the catalytic activity of the cathode and an i...

AI Technical Summary

Problems solved by technology

[0003] Chen et al. (Yan Chen, Zhuhua Cai, Yener Kuru, Wen Ma, Harry L.Tuller, Bilge Yildiz, Advanced Energy Materials, 2013, 3, 1221.) prepared La 0.8 Sr 0.2 CoO 3 / (La 0.5 Sr 0.5 ) 2 CoO 4 The multilayer film with heterogeneous interface structure can increase the oxygen reduction reaction rate by several orders of magnitude at 500 ° C, and the oxygen reduction catalytic activity of the cathode is significantly enhanced. However, this multilayer film material requires expensive and special preparation equipment, which is not conducive to Mass production and large-scale application of the cathode, and cannot solve the CO of the cathode 2 Surface adsorption poisoning and high thermal expansion coefficient problems

Zhou et al. (Wei Zhou, Fengli Liang, Zongping Shao, Zhonghua Zhu, Scientific Reports, 2012, 2 : 327) used solution osmosis-microwave plasma heating method in Ba 0.5 Sr 0.5 co 0.8 Fe 0.2 o 3-δ (BSCF) Particle surface preparation of La 2 NiO 4+δ protective layer that improves the BSCF cathode in the presence of CO 2 Oxygen reduction reaction catalytic activity and performance stability in the atmosphere, in order to solve the CO of perovskite cathode containing alkaline earth metal ions 2 The surface adsorption poisoning problem provides an effective solution, however, due to the La 2 NiO 4+δ The oxygen ion conductivity of the protective layer is low, which is not conducive to the oxygen surface exchange process of the cathode, resulting in low oxygen reduction catalytic activity of the prepared cathode, and there is still the problem of high thermal expansion coefficient

Images