Dimensional analysis of Ni‐NiO grains at anode/electrolyte interface for SOFC during redox reaction

Abstract

Upon reduction and re‐oxidization, the interface of a microtubular solid oxide fuel cell (MTSOFC) anode/electrolyte was structurally analyzed using a dual beam focused ion beam/scanning electron microscope (FIB/SEM) and scanning transmission electron microscopy combined with energy dispersive X‐ray spectrometer (STEM‐EDX). The bulk volume of the dense NiO phase dramatically contracted upon reduction, while the YSZ phases are completely unaffected. No cracks or particle detachment are observed either at the interface of the anode/electrolyte or in the anode backbone. Compared with the initial NiO state (as‐prepared), the area of Ni phase contracts by 22.6%‐83.7%, depending on the grain size.

Recent Development in Reversible Solid Oxide Fuel Cells: Theory, Integration and Prospective

“…This is highly correlated with the accumulation of excessive oxygen ions in the fuel electrode due to fuel supply interruptions, emergency shutdowns, and alternating operation and mode-switching operations during RSOC operation. [94] V.N. Nguyen et al [95] conducted long-term tests on RSOC stacks, finding a higher degradation rate in co-electrolysis conditions.…”

“…The instability of redox reactions is one of the primary degradation issues affecting dual‐mode operation, attributed to the re‐oxidation of particles in the functional layer. This is highly correlated with the accumulation of excessive oxygen ions in the fuel electrode due to fuel supply interruptions, emergency shutdowns, and alternating operation and mode‐switching operations during RSOC operation [94] . V.N.…”

Structure evaluation of anode‐supported planar solid oxide fuel cells based on single/double‐sided electrolyte(s) under redox conditions

“…Therefore, to improve the operational reliability of cells, a series of methods were tried, such as modification of the anode support, using reductive atmosphere for protection, implementing an inert gas emergency system, decreasing NiO particle size, adding several transition layers between the anode and electrolyte, and even switching to electrolyte‐supported SOFCs. [] However, above 600℃ the ASC (Anode‐supported solid oxide fuel cell) still exhibited the deformation during operation and hardly withstood one or more redox process.…”

Electrical properties of Y/Mg modified NiO simple oxides for negative temperature coefficient thermistors

“…Nickel oxide (NiO) is a typical semiconducting compound with band gap of about 3.6 eV. NiO has received great interest for applications in lithium ion battery, supercapacitor, solar cell, fuek cell and gas sensor, etc …”