Fabrication of REVO4 films via sacrificial conversion from layered rare-earth hydroxide (LRH) films: the investigation of the transition mechanism and their photoluminescence

He Zhang; Taihui Chen; Sen Qin; Junjie Huang; Xiaoli Wu

doi:10.1039/d1dt03724b

Fabrication of REVO₄ films via sacrificial conversion from layered rare-earth hydroxide (LRH) films: the investigation of the transition mechanism and their photoluminescence

Dalton Trans. 2022 Apr 5;51(14):5577-5586. doi: 10.1039/d1dt03724b.

Authors

He Zhang¹, Taihui Chen¹, Sen Qin¹, Junjie Huang^{1

2}, Xiaoli Wu^{1

3}

Affiliations

¹ College of Materials Science and Engineering, Guilin University of Technology, Guilin 541004, People's Republic of China.
² Collaborative Innovation Center for Exploration of Hidden Nonferrous Metal Deposits and Development of New Materials in Guangxi, Guilin University of Technology, Guilin 541004, People's Republic of China.
³ Guangxi Key Laboratory of Optical and Electronic Materials and Devices, Guilin University of Technology, Guilin 541004, People's Republic of China. wuxiaoli@glut.edu.cn.

PMID: 35312739
DOI: 10.1039/d1dt03724b

Abstract

Rare-earth orthovanadate REVO₄ (RE = La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, and Y) films were directly synthesized within 2 hours by sacrificial conversion from electrodeposited layered rare-earth hydroxide (RE₂(OH)₅NO₃·nH₂O) films at pH ∼ 10, without subsequent heat treatment. Detailed characterization of the products was achieved by combined X-ray diffraction, Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and photoluminescence excitation and photoluminescence. The mechanisms of phase and morphology evolution from Y₂(OH)₅NO₃·nH₂O to YVO₄ were unveiled through systematic investigations into the influences of the concentration of the anion sources (Na₃VO₄) and the reaction temperature. The effects of lanthanide contraction on the phase structure and particle morphology of the REVO₄ films were also clarified. Additionally, the photoluminescence of RE³⁺ activators (RE = Eu, Dy, and Eu and Dy) was elaborated with YVO₄ as a representative host lattice, and the color-tunable emission and energy transfer from Dy³⁺ to Eu³⁺ were also investigated. Electrodeposition combined with a hydrothermal anion exchange technique established in this study led to the rapid synthesis of REVO₄ films, and it might have wide implications for the generation of other types of inorganic functional films.