Fabrication and properties of high efficiency luminescent nanorods EuPO4·H2O by soft template method

Europium orthophosphate monohydrate (EuPO4·H2O) nanorods with typical dimensions of about 10–30 nm in diameter and 300–500 nm in length were prepared by using the soft template method. The effects of using diethylene glycol (DEG) and polyethylene glycol (PEG) polymers as well as the pH values on the size, crystalline structure and morphology of EuPO4·H2O nanorods were investigated. Field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) data of the prepared samples were elucidated. The nanorods were highly uniform and their mean length was reduced by using DEG and PEG as soft template agents. For all prepared samples, the rhabdophane-type hexagonal EuPO4·H2O was the dominated phase. The photoluminescence (PL) spectroscopy measurements of EuPO4·H2O nanorods revealed that, under UV excitation, EuPO4·H2O nanorods exhibited strong luminescence with narrow bands corresponding to the intra-4f transitions of 5D0→7Fj (j=1, 2, 3, 4) of Eu3+ ions. The peaks were found at 594 nm (5D0→7F1), 619 nm (5D0→7F2), 652 nm (5D0→7F3), and 697 nm (5D0→7F4), with the strongest emission at 594 nm.