Controllable Synthesis and Luminescence Properties of Zn₂GeO₄ : Mn²⁺ Nanorod Phosphors

Abstract

In this study, color tunable phosphors (Mn 2 + -doped Zn 2 GeO 4 ) were successfully synthesized by a facile microwave hydrothermal process with H 2 O as solvent. Crystal field modulation and band gap doping by Mn 2 + substitution for Zn 2 + realizes color tunable Mn 2 + emission from 424 to 535 nm. Mn 2 + -doping on the phase and size transition of Zn 2 GeO 4 nanocrystals was discussed, and a possible Zn 2 GeO 4 : xMn crystal growth mechanism is discussed. Photoluminescence (PL) spectra indicate that the d-d transition of manganese ions ( 4 T 1 ! 6 A 1 ) corresponds to a strong green emission of Zn 2 GeO 4 : xMn phosphors.

Dynamic Luminescence of Lead-Doped Calcium Zinc Germanate Clinopyroxene for Multimode Anticounterfeiting

“…Numerous studies have focused on utilizing germanate as a host material that contains various dopants to create phosphor materials with exceptional luminescent properties. For example, germanate material Zn 2 GeO 4 (ZGO) has been intensively studied in the last few decades, − and ZGO-based phosphor materials have been utilized in anticounterfeiting labels with excellent outcomes. − Other germanate materials could also be good candidates for anticounterfeiting applications. One such material is CaZnGe 2 O 6 [calcium zinc germanate (CZGO)], which is a clinopyroxene material utilized in long persistent luminescence phosphors. − The dopants used in CZGO clinopyroxene include chromium (Cr); , manganese (Mn); , bismuth (Bi); , dysprosium (Dy); terbium (Tb), and lead (Pb) .…”

Persistent Luminescence Zn2GeO4:Mn2+ Nanoparticles Functionalized with Polyacrylic Acid: One-Pot Synthesis and Biosensing Applications

“…Zn 2 GeO 4 :Mn 2+ rod-like NPs with large aspect ratios are indeed reported in the vast majority of studies about PLNPs of this material. Such studies reported Zn 2 GeO 4 :Mn 2+ rods obtained by hydrothermal reaction of zinc and manganese nitrates and germanium oxide in alkaline conditions in the absence of any additive, where the dimensions of the rods are determined by the temperature, time, and pH of the reaction. − However, although it is essential that the NPs to be used in biomedicine are monodisperse in nature and exhibit colloidal and chemical stability in physiological medium, these physicochemical features have never been demonstrated for the reported Zn 2 GeO 4 :Mn 2+ nanorods by suitable methods such as dynamic light scattering (DLS) and ion coupling plasma (ICP) . In addition, despite the importance of surface functionalization for bioapplications, only a few studies report surface-functionalized Zn 2 GeO 4 :Mn 2+ NPs, all of which require a second-stage functionalization reaction following the hydrothermal synthesis. − , …”