RESUMO
In this work, a simple one-step hydrothermal method was employed to prepare the Ce-doped Fe2O3 ordered nanorod arrays (CFT). The Ce doping successfully narrowed the band gap of Fe2O3, which improved the visible light absorption performance. In addition, with the help of Ce doping, the recombination of electron/hole pairs was significantly inhibited. The external voltage will make the performance of the Ce-doped sample better. Therefore, the Ce-doped Fe2O3 has reached superior photoelectrochemical (PEC) performance with a high photocurrent density of 1.47 mA/cm2 at 1.6 V vs. RHE (Reversible Hydrogen Electrode), which is 7.3 times higher than that of pristine Fe2O3 nanorod arrays (FT). The Hydrogen (H2) production from PEC water splitting of Fe2O3 was highly improved by Ce doping to achieve an evolution rate of 21 µmol/cm2/h.
RESUMO
Some kinds of phosphors were synthesized with Eu/Dy coating ZnO nanocrystals by co-precipitation approach derived from Zn(AC)2 2H2O, NaOH as precursors. The crystal structure and size were characterized by the X-ray diffraction Photoluminescence(PL) measurements show an intense red luminescence at 612 nm caused by transition of Eu3+ ions in ZnO:Eu3+ and intense luminescence band at 484 and 575 nm caused by transition of Dy3+ ions in ZnO:Dy3+. The results show that the energy transfer was realized from the host to the rare earth ions. The mechanism of the energy transfer was discussed. Meanwhile Eu/Dy co-coating nano ZnO can be achieved white light emission by energy transfer.