Synthesis, characterization, and luminescence studies of lead zinc germanate (PbZnGe2O6) phosphors — 33a — Anika Nawar Chowdhury

Luminescent materials or phosphors are substances that emit light when being excited. These materials have significant applications in security, optoelectronics, bioimaging, sensors, and other fields. Recently, some studies showed that germanate based phosphors with various dopants could have different color emissions. Metal-doped calcium zinc germanate (CZGO), which has a clinopyroxene structure, shows excellent optical properties. According to the studies, dynamic fluorescence and photochromism is observed when doped with lead ions. It is hypothesized that, as lead and calcium ions are similar in size, these divalent cations can be interchanged in the lattice. In addition, understanding the host and dopant interactions is crucial for developing various germanate based phosphors. In this study, we synthesized a new material lead zinc germanate (LZGO) as a host and doped with calcium ions. The compounds were synthesized at a high temperature using a solid-state reaction. The compounds show blue and green fluorescence under 254 nm and 365 nm excitation, respectively. Spectrofluorometer has been used for performing photoluminescence studies. A systematic photoluminescence study of the phosphors has been conducted using different dopant concentrations and reaction time for synthesis. The increase of reaction time and dopant concentrations showed more intense green fluorescence. In addition, powder X-ray diffraction experiments have been conducted to study the samples’ crystallinity. This study shows that dopant concentrations and reaction time can play a significant role in the photoluminescence properties of the LZGO phosphors.

University of South Dakota
Dr. Chaoyang Jiang