CeO纳米结构形态演变过程中的电学性质变化：体缺陷与表面缺陷之间的协同作用。

Electric Properties Change during Morphological Evolution of CeO Nanostructures: Synergy between Bulk and Surface Defects.

作者信息

Macchi Carlos, Procópio Alley M S, Rocha Leandro S R, Ortega Pedro P, Aldao Celso M, Granone Luis I, Nascimento Hugo M S, Longo Elson, Castro Miriam S, Ivorra Fernando D, Somoza Alberto, Moura Francisco, Ponce Miguel A

机构信息

CIFICEN (UNCPBA-CICPBA-CONICET) and Materials Physics Institute (IFIMAT), National University of Central Buenos Aires (UNCPBA), Tandil 7000, Argentina.

Advanced Materials Interdisciplinary Laboratory (LIMAv), Federal University of Itajubá, Itabira, Minas Gerais 35903-087, Brazil.

出版信息

ACS Omega. 2024 Oct 3;9(41):42172-42182. doi: 10.1021/acsomega.4c03210. eCollection 2024 Oct 15.

DOI:10.1021/acsomega.4c03210

PMID:39431077

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11483379/

Abstract

CeO samples were synthesized via the polymeric precursor method at different calcination temperatures. Electric properties were investigated using positron annihilation lifetime spectroscopy, electron paramagnetic resonance spectroscopy, and complex impedance spectroscopy. Reduction in the specific surface area of the particles with increasing calcination temperature along with morphological changes were observed. PALS depicted doubly ionized oxygen vacancies surrounded by two Ce3+ atoms, while the EPR spectroscopy showed a singly ionized oxygen vacancy surrounded by Ce3+ and Ce4+ ions. Impedance measurements unraveled the presence of polarons, while thermal treatments led to a lower electrical conductance, as the calcination temperature increased.

摘要

通过聚合物前驱体法在不同煅烧温度下合成了CeO样品。使用正电子湮没寿命谱、电子顺磁共振谱和复阻抗谱研究了电学性质。观察到随着煅烧温度升高，颗粒的比表面积减小以及形态发生变化。正电子湮没寿命谱描绘了被两个Ce3+原子包围的双电离氧空位，而电子顺磁共振谱显示了被Ce3+和Ce4+离子包围的单电离氧空位。阻抗测量揭示了极化子的存在，而随着煅烧温度升高，热处理导致电导率降低。