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Synthesis, characterization and photoluminescence of ­Dy3+‑doped MgZnO nanophosphors Preasha Rajput1 · Pargam Vashishtha2 · Govind Gupta2 · Pragati Singh3 · Kamni Pathania1  Received: 4 May 2020 / Accepted: 30 June 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020

Abstract MgZnO and MgZnO: D ­ y3+ (x = 0.0025–0.025) nanoparticles were synthesized by the combustion method. The as-synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), UV–visible spectroscopy (UV–Vis) and photoluminescence (PL) techniques. XRD studies confirmed the presence of wurtzite hexagonal structure of all the samples with the crystallite size in the range of 30–50 nm range. The XRD results were also in good agreement with the TEM results. The EDS spectra confirmed the presence of all the elements in the samples prepared. UV–Vis measurements indicated variation in bandgap values with increasing doping concentration. PL spectrum showed enhanced blue emission and tunability of blue emission could be observed with variation in dopant concentration. Excellent emission intensity of the phosphor was suitable for application in display devices. Keywords  Combustion synthesis · Nanophosphors · XRD · UV–visible spectroscopy · TEM · Photoluminescence

1 Introduction MgZnO is a novel ternary alloy. Due to its high bandgap 3.3–7.8 eV, stability and highly oxidic nature MgZnO has the potential application in wide range of optoelectronic applications [1–4]. Recently, ternary XZnO (X = Mg, Be, Sr) alloys have shown to be promising phosphor materials [5]. A bright ultraviolet (UV) luminescence at room temperature that is excitonic in nature is shown by this alloy [6]. Moreover, based on bandgap tunability, MgZnO alloys have been shown to be suitable material for realization of heterojunctions [7]. This material effectively shows emission in UV, blue, green and red region, but the optical properties of the material can be effectively enhanced by suitable doping. The rare earth elements are the most wonderful candidates for modulating the emission of host matrix. Among all the available rare earth elements, dysprosium (­ Dy3+) is the most * Kamni Pathania [email protected] 1



School of Physics, Shri Mata Vaishno Devi University, Katra 182320, Jammu and Kashmir, India

2



CSIR‑National Physical Laboratory, Sensor Devices and Metrology Group, New Delhi, India

3

Department of Physics, Indian Institute of Technology (BHU), Varanasi, India



important rare earth ion for the preparation of phosphors and also plays a major role in the production of white light luminescent materials [8, 9]. Based on the host environment, several emission bands are emitted by D ­ y3+ between its f–f transitions [10]. Although structural and spectral properties of MgZnO have been studied extensively, reports on structural and spectral properties D ­ y3+-doped MgZnO have rarely been reported. This encouraged the author to systematically study MgZnO: ­Dy3+ s