Break the Interacting Bridge between Eu3+ Ions in the 3D Network Structure of CdMoO4: Eu3+ Bright Red Emission Phosphor

Weiguang Ran,Jung Hwan Kim,Byung Kee Moon,Jinsheng Shi,Hyeon Mi Noh,Sung Heum Park,Jung Hyun Jeong

doi:10.1038/s41598-018-24374-3

Abstract

Eu3+ doped CdMoO4 super red emission phosphors with charge compensation were prepared by the traditional high temperature solid-state reaction method in air atmosphere. The interrelationships between photoluminescence properties and crystalline environments were investigated in detail. The 3D network structure which composed by CdO8 and MoO4 polyhedra can collect and efficiently transmit energy to Eu3+ luminescent centers. The relative distance between Eu3+ ions decreased and energy interaction increased sharply with the appearance of interstitial occupation of O2− ions ({O^{primeprime} }_{i}). Therefore, fluorescence quenching occurs at the low concentration of Eu3+ ions in the 3D network structure. Fortunately, the charge compensator will reduce the concentration of {O^{primeprime} }_{i} which can break the energetic interaction between Eu3+ ions. The mechanism of different charge compensators has been studied in detail. The strong excitation band situated at ultraviolet and near-ultraviolet region makes it a potential red phosphor candidate for n-UV based LED.

Highlights

Eu3+ doped CdMoO4 super red emission phosphors with charge compensation were prepared by the traditional high temperature solid-state reaction method in air atmosphere
The structure refinement of the CdMoO4, Cd0.96MoO4:0.04Eu3+ and Cd0.96−yMoO4:0.04Eu3+, yM (M = Li+, Na+, K+ and Cd2+ vacancy) samples was performed using the GSAS II software package[22] and the initial parameters of refinement for CdMoO4 sample were referred from the single crystal data of CdMoO4 (ISCD-84455)
A series of Eu3+ and alkali metal ions co-doped CdMoO4 phosphors were prepared by the solid-state reaction method in air atmosphere

Summary

Introduction

Eu3+ doped CdMoO4 super red emission phosphors with charge compensation were prepared by the traditional high temperature solid-state reaction method in air atmosphere. The strong excitation band situated at ultraviolet and near-ultraviolet region makes it a potential red phosphor candidate for n-UV based LED. With the development of LED chip technology, the emission bands of LED chips shifted from blue light to near-UV range which can offer higher energy to pump the phosphor[9]. Cadmium molybdate CdMoO4 with scheelite-type structure have attracted considerable interest due to its potential applications in phosphors, scintillators, magnets and catalysts[13,14]. Guzik[18] has prepared scheelite-type Cd1–3xEu2x□xMoO4 phosphors by high temperature solid phase reaction method with CdMoO4. The effect of Cd2+ vacancy on the occupied position of doping ions in CdMoO4 was investigated for the first time[18,20]

Methods

Results

Conclusion