Electrospinning preparation and upconversion luminescence of Y 2 Ti 2 O 7 :Tm/Yb nanofibers
- PDF / 6,134,978 Bytes
- 8 Pages / 595.276 x 790.866 pts Page_size
- 13 Downloads / 226 Views
Electrospinning preparation and upconversion luminescence of Y2Ti2O7:Tm/Yb nanofibers Hongquan Yu1 · Piaopiao Jiang2 · Baojiu Chen1 · Jiashi Sun1 · Lihong Cheng1 · Xiangping Li1 · Jinsu Zhang1 · Sai Xu1 Received: 29 May 2020 / Accepted: 5 August 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Nanoscale Y2Ti2O7:Tm3+/Yb3+ fibers were fabricated through electrospinning followed by calcining at high temperatures. The resulting Y 2Ti2O7:Tm3+/Yb3+ fibers were characterized by XRD, SEM, TEM, EDX, and ICP-OES. The average diameter of the Y 2Ti2O7:Yb/Tm nanofibers is about 80 nm and they are hundreds of microns long. Their upconversion (UC) intensity was found to increase with increasing Y b3+ concentration within the working current range of 1.50–2.50 A under 980-nm laser irradiation. The mechanism of energy transfer between Y b3+ to T m3+ ions in the Y2Ti2O7:Yb/Tm nanofibers was also elucidated The three-photon processes and the two-photon processes were confirmed to be involved in blue emissions and red and near-infrared emission by analyzing the UC-intensity dependence on the operating current of the 980-nm exciting laser. Keywords Y2Ti2O7:Tm3+/Yb3+ nanofibers · Electrospinning · Luminescent properties
1 Introduction Nanomaterials doped with lanthanide have found their applications in many fields, including lighting, cathode ray tubes, field emission displays, plasma display panels, biological labeling, solar cells, and so on due to their optical and electronic properties because of their 4f electrons [1]. In contrast to bulk materials, one-dimensional (1D) and quasi-1D nanostructures provide better models to study dependences of optical and electronic transport properties upon morphologies and structures [2]. In recent years, 1D and quasi-1D nanomaterials, such as nanowires, nanorods, and nanotubes, have aroused interest of many scholars. This is because these materials have useful properties, e.g. good luminescence efficiencies, metal–insulator transitions, excellent
* Hongquan Yu [email protected] * Baojiu Chen [email protected] 1
Department of Physics, Dalian Maritime University, No. 1, Linghai Road, Dalian 116026, Liaoning, People’s Republic of China
College of Environmental and Chemical Engineering, Dalian Jiaotong University, Dalian 116028, Liaoning, People’s Republic of China
2
mechanical toughness, lower thresholds, and being able to form ideal systems for building functional devices [3–5]. In recent years, pyrochlore oxides (cubic, Fd3m) whose general formula is A2B2O7 have attracted lots of interest to be used as a host material of trivalent lanthanide activators [6]. Eight-coordinated A sites of such A2B2O7 compounds tend to be occupied by relatively large cations like Gd3+ and Y3+ and are rested inside distorted cubic polyhedra. On the other hand, the six-coordinated B sites are generally taken up by smaller transition-metal cations, such as Zr4+ and Ti4+; these sites are situated inside distorted octahedra made up of oxygen ions [7]. Pyrochlore oxid
Data Loading...
