Hydrothermal-assisted exfoliation of Y/Tb/Eu ternary layered rare-earth hydroxides into tens of micron-sized unilamellar nanosheets for highly oriented and color-tunable nano-phosphor films [dataset]

Qi Zhu, Zhixin Xu, Ji-Guang Li, Xiaodong Li, Yang Qi, Xudong Sun
2016 nano Online   unpublished
Efficient exfoliation of well-crystallized (Y 0.96 Tb x Eu 0.04-x ) 2 (OH) 5 NO 3 · nH 2 O (0 ≤ x ≤ 0.04) layered rare-earth hydroxide (LRH) crystals into tens of micron-sized unilamellar nanosheets has been successfully achieved by inserting water insoluble oleate anions (C 17 H 33 COO − ) into the interlayer of the LRH via hydrothermal anion exchange at 120°C, followed by delaminating in toluene. The intercalation of oleate anions led to extremely expanded interlayer distances (up to
more » ... ces (up to approximately 5.2 nm) of the LRH crystals and accordingly disordered stacking of the ab planes along the c-axis and also weakened interlayer interactions, without significantly damaging the ab plane. As a consequence, the thickness of the LRH crystals increased from approximately 1 to 10 μm, exhibiting a behavior similar to that observed from the smectite clay in water. Highly [111]-oriented and approximately 100-nm thick oxide films of (Y 0.96 Tb x Eu 0.04-x ) 2 O 3 (0 ≤ x ≤ 0.04) have been obtained through spin-coating of the exfoliated colloidal nanosheets on quartz substrate, followed by annealing at 800°C. Upon UV excitation at 266 nm, the oxide transparent films exhibit bright luminescence, with the color-tunable emission from red to orange, yellow, and then green by increasing the Tb 3+ content from x = 0 to 0.04.
doi:10.1515/nano.11671_2015.179 fatcat:dfu65traz5fqpnds4tt4rkq2nq