Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia

In recent years, the utilisation of oxygen-deficient zirconia (ZrO2-α), commonly referred to as black zirconia, has garnered considerable attention due to its potential applications for solid oxide fuel cells (SOFCs), gas sensors, biomedical implant materials, and photocatalysis. However, current me...

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Main Authors: Fangzhou Shi, Behnam Dashtbozorg, Xiaoying Li, Hanshan Dong
Format: Article
Language:English
Published: Elsevier 2024-03-01
Series:Journal of Materials Research and Technology
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2238785424004046
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author Fangzhou Shi
Behnam Dashtbozorg
Xiaoying Li
Hanshan Dong
author_facet Fangzhou Shi
Behnam Dashtbozorg
Xiaoying Li
Hanshan Dong
author_sort Fangzhou Shi
collection DOAJ
description In recent years, the utilisation of oxygen-deficient zirconia (ZrO2-α), commonly referred to as black zirconia, has garnered considerable attention due to its potential applications for solid oxide fuel cells (SOFCs), gas sensors, biomedical implant materials, and photocatalysis. However, current methods employed to manufacture ZrO2-α exhibit noticeable limitations regarding their scalability, environmental sustainability, and cost-effectiveness. Our recent work has successfully demonstrated the feasibility for bulk conversion of conventional white zirconia into oxygen-deficient black zirconia through direct current (DC) plasma treatment (i.e. plasma blackening). This study elucidates the conditions for plasma blackening and provides a unique mechanism for the bulk transformation of zirconia. A systematic investigation of different plasma technologies (DC, active-screen plasma), treatment configurations (contact conditions, cathode material, and cathode potential), and treatment parameters (voltage, temperature, duration) uncover the crucial variables that influence the feasibility and rate of the reduction process. The reduction of zirconia is shown to initiate from localised contacting points at the cathode-facing surface and grow, with a hemispherical shape, towards the anode-facing surface. A series of development stages are proposed for the process, namely: bulk oxygen vacancy conductance, surface activation, oxygen vacancy generation and a moving cathode front. The findings of this study provide insights into the underlying mechanisms involved in the bulk-reduction of zirconia and help to pave the way towards future scalable and cost-effective generation of oxygen-deficient zirconia.
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spelling doaj.art-3551b028ef7b4f2991806c0929b90cf22024-03-24T06:58:21ZengElsevierJournal of Materials Research and Technology2238-78542024-03-012937593770Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconiaFangzhou Shi0Behnam Dashtbozorg1Xiaoying Li2Hanshan Dong3School of Metallurgy & Materials, University of Birmingham, Birmingham, B15 2TT, UKCorresponding author.; School of Metallurgy & Materials, University of Birmingham, Birmingham, B15 2TT, UKSchool of Metallurgy & Materials, University of Birmingham, Birmingham, B15 2TT, UKSchool of Metallurgy & Materials, University of Birmingham, Birmingham, B15 2TT, UKIn recent years, the utilisation of oxygen-deficient zirconia (ZrO2-α), commonly referred to as black zirconia, has garnered considerable attention due to its potential applications for solid oxide fuel cells (SOFCs), gas sensors, biomedical implant materials, and photocatalysis. However, current methods employed to manufacture ZrO2-α exhibit noticeable limitations regarding their scalability, environmental sustainability, and cost-effectiveness. Our recent work has successfully demonstrated the feasibility for bulk conversion of conventional white zirconia into oxygen-deficient black zirconia through direct current (DC) plasma treatment (i.e. plasma blackening). This study elucidates the conditions for plasma blackening and provides a unique mechanism for the bulk transformation of zirconia. A systematic investigation of different plasma technologies (DC, active-screen plasma), treatment configurations (contact conditions, cathode material, and cathode potential), and treatment parameters (voltage, temperature, duration) uncover the crucial variables that influence the feasibility and rate of the reduction process. The reduction of zirconia is shown to initiate from localised contacting points at the cathode-facing surface and grow, with a hemispherical shape, towards the anode-facing surface. A series of development stages are proposed for the process, namely: bulk oxygen vacancy conductance, surface activation, oxygen vacancy generation and a moving cathode front. The findings of this study provide insights into the underlying mechanisms involved in the bulk-reduction of zirconia and help to pave the way towards future scalable and cost-effective generation of oxygen-deficient zirconia.http://www.sciencedirect.com/science/article/pii/S2238785424004046ZirconiaDC plasmaOxygen vacanciesMoving cathodeReduction
spellingShingle Fangzhou Shi
Behnam Dashtbozorg
Xiaoying Li
Hanshan Dong
Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
Journal of Materials Research and Technology
Zirconia
DC plasma
Oxygen vacancies
Moving cathode
Reduction
title Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
title_full Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
title_fullStr Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
title_full_unstemmed Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
title_short Processing conditions and mechanisms for the plasma defect-engineering of bulk oxygen-deficient zirconia
title_sort processing conditions and mechanisms for the plasma defect engineering of bulk oxygen deficient zirconia
topic Zirconia
DC plasma
Oxygen vacancies
Moving cathode
Reduction
url http://www.sciencedirect.com/science/article/pii/S2238785424004046
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AT xiaoyingli processingconditionsandmechanismsfortheplasmadefectengineeringofbulkoxygendeficientzirconia
AT hanshandong processingconditionsandmechanismsfortheplasmadefectengineeringofbulkoxygendeficientzirconia