Electrocatalytic Performance Evaluation Of SrCo_0.9Nb_0.1O_3-? Based Bifunctional Oxygen Electrodes

Realizing the sustainable development of society is the common goal pursued in the 21st century.The solution to the energy problem has always been the focus of people's work.After long-term research,low-cost environmentally friendly fuel cells and metal-air batteries are the most promising energy conversion and storage devices,which can realize the mutual conversion of electrical energy and chemical energy.The development of high-efficiency dual-function oxygen electrode catalysts is the key to improving the performance of two types of batteries.In recent years,high activity and stability of perovskite materials developed by anion and cation doping have become research hotspots.In this paper,the perovskite-type oxide SrCoO₃?SCO?is used as the basic material and optimized.Including Co-doped high-valent cation Nb⁺⁵SCN_0.1,SCN_0.2 and SCNF samples were prepared by high temperature solid phase synthesis.Room temperature ORR/OER catalytic performance and stability tests of SCN_0.1,SCN_0.2 and SCNF electrodes were carried out by a three-electrode method using a rotating disk electrode device;SCN_0.1 and SCNF were used as oxygen electrodes for zinc-air batteries.The catalyst was subjected to performance tests such as polarization curves and constant current discharge.The three-electrode method was used to test the high temperature electrocatalytic activity of SCN_0.1 and SCNF electrodes.Finally,the Cr deposition and electrode poisoning of SCN_0.1 under different operating conditions were also studied.The paper further studied the sample composition and microstructure by means of X-ray diffraction and scanning electron microscopy.The room temperature electrochemical tests of SCN_0.1,SCN_0.2.2 and SCNF electrodes show that the SrCoO₃?SCO?is doped with 10%Nb⁺⁵ by Co-doping to obtain the ORR and OER catalytic activity and stability of SCN_0.1 material.good.The bifunctional catalytic activity of SCNF material was obtained after O-site F-ion doping on the basis of SCN_0.1,and the reversibility and stability were further improved.When the SCN_0.1 and SCNF materials are used as catalysts for zinc-air batteries and solid oxide batteries,they show good catalytic performance,which proves their practical application value in room temperature and medium-low temperature batteries.In summary,the SCN_0.1-based composite oxygen electrode catalyst has good bifunctional catalytic activity and long-term stability,but its anti-Cr poisoning ability is poor,so attention should be paid to the protection of the oxygen electrode when used as a SOFC cathode.Avoid the phenomenon of Cr poisoning.