Detection of oxide-ion and oxygen vacancy swapping upconversion luminescence in LaMoO:Yb,Er

• Published in: Journal of materials chemistry. C, Materials for optical and electronic devices Materials for optical and electronic devices, 2016-07, Vol.4 (3), p.7286-7293
• Main Authors: Li, Ye, Jiang, Xiao-Fang, Tao, Feng-Qiong, Yang, Yan-Min, Zhang, Qin-Yuan, Ye, Shi
• Format: Article
• ISSN: 2050-7526; 2050-7534
• DOI: 10.1039/c6tc01875k

It is requisite to detect thermally activated oxide-ion motion in oxide-ion conductors via an in situ non-contact method when applied in solid oxide fuel cells, oxygen sensors and oxygen separation. This research conceptually proposes an alternative approach by using the upconversion (UC) luminescence of Yb 3+ -Er 3+ in La 2 Mo 2 O 9 oxide-ion conductors. According to the results, the temperature-dependent UC luminescence intensity ratio of 2 H 11/2 → 4 I 15/2 to 4 F 9/2 → 4 I 15/2 transitions of Er 3+ can reveal the activation process of oxide-ion and oxygen vacancy swapping at 150-200 °C in α-La 2 Mo 2 O 9 , which has a break point in the plot. It is also evidenced and confirmed by the temperature-dependent UC decay curves, temperature-dependent alternating current (AC) impedance data, temperature-dependent internal friction data and temperature-dependent Raman data. The analysis according to Judd-Ofelt theory supports this point as well. This research may promote new applications of luminescence, and offer an alternative approach to design novel multifunctional materials. The oxide-ion and oxygen vacancy swapping in the oxide-ion conductor La 2 Mo 2 O 9 :Yb 3+ ,Er 3+ can be detected by upconversion luminescence as a novel non-contact approach.