Nuclear Techniques ›› 2016, Vol. 39 ›› Issue (6): 60102-060102.doi: 10.11889/j.0253-3219.2016.hjs.39.060102

• SYNCHROTRON RADIATION TECHNOLOGY AND APPLICATIONS • Previous Articles     Next Articles

Analysis of three-dimensional microstructure evolution of tested Ni-YSZ anodes by Nano-CT

GUO Pengfei, GUAN Yong, LIU Gang, TIAN Yangchao   

  1. National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029, China
  • Received:2016-03-23 Revised:2016-04-25 Online:2016-06-10 Published:2016-06-12
  • Supported by:

    Supported by National Natural Science Foundation of China (No.11275204, No.11475175, No.11405175, No.11205189), the Major State Basic Research Development Program of China (973 Program)(No.2012CB825804)

Abstract:

Background: Anode in solid oxide fuel cell (SOFC) provides three-phase boundary (TPB) regions for electrochemical reactions and plays an active role in mass transfer, gas diffusion and isolation between different substances.Purpose: During operation, the microstructure of anode will be changed.Research on microstructural evolution of SOFC anode can help us understand performance degradation of SOFC after long time operation.Methods: Recently, development of X-ray nano-CT (Computed Tomography) makes it possible to nondestructively obtain the three-dimensional (3D) microstructural change of anodes subjected to no test and test for 20 h.Some quantitative analysis methods developed in house are applied to obtain key parameters of microstructures.Results: Based on the reconstructions of anode 3D microstructures, some parameters of microstructures are measured, such as particle size, volume fraction of each phase and connectivity for each phase.The average particle size of Ni increases after SOFC test, while the Ni-phase connectivity and TPB density of tested anode decrease, which is caused by the aggregation and growth of Ni particles.Conclusion: The data of untested and tested anode microstructures shows that the agglomeration of Ni particles occurs and internal structure of anode has changed after SOFC test, which may be a main reason causing performance degradation of SOFC during long time operation.This shows that X-ray nano-CT is a powerful tool to study energy materials and provides important data for optimizing the microstructure of anode.

Key words: X-ray CT, Ni-YSZ anode, 3D microstructure, Connectivity

CLC Number: 

  • O434.19