Synthesis, morphology and optical properties characterization of Zn₂GeO₄:Mn pH-size dependent nanomaterials

Abstract

Zn2GeO4:Mn (ZGO:Mn) is one of a materials known from its efficient persistent luminescence properties. Such materials are capable of storing excitation energy in crystal structure defects, inner traps such as holes or electrons, whereas once excited can remain luminescence properties after source of the excitation has stopped [1]. This interesting property opens up the potential use of these type of materials for biomedical applications, e.g., bioimaging, therefore the crucial issue is the proper synthesis approach to ensure the nanometer size and monodispersity of the obtained ZGO:Mn materials [2]. In this work, with the use of hydrothermal, microwave assisted synthesis, six different nanomaterials based on the same Zn2GeO4:Mn matrix have been obtained. Each synthesis was carried out for different pH values, i.e. 6.0; 7.0; 7.5; 8.0; 8.5; 9.5, respectively. Morphology of the synthesized ZGO:Mn have been characterized by the transmission electron microscopy (TEM). On the basis of the measured images, size distributions have been calculated. The crystal structure has been confirmed by X-ray powder diffraction (XRD) method. Optical properties (excitation and emission spectra) have been investigated via spectrofluorometer. Use of various pH values during the synthesis process resulted in nanoparticles that differs in size values, what has been confirmed via measured size distribution histograms. The luminescence properties due to the doping of manganese (II) ions was confirmed by spectroscopic measurements. Currently, the first attempts are planned to characterize the persistent luminescence properties of the obtained functional materials, and towards surface functionalization.

Publication
2nd International Conference on Advanced Materials for Bio-Related Applications