Template-free synthesis, characterization, growth mechanism and photoluminescence property of Eu(OH)3 and Eu2O3 nanospindles

A simple aqueous solution route was introduced for the fabrication of uniform Eu(OH)3 and Eu2O3 nanospindles, nanorods and nanobundles by using Eu(NO3)3 and NaOH as the starting reaction reagents at room temperature and atmosphere pressure without any surfactant and template. The influence of the molar ratios of [OH−]/[Eu3+], reaction time, and temperature was investigated. It is demonstrated that the size of Eu(OH)3 nanospindle can be well tuned by adjusting the [Eu3+]/[OH−] molar ratios. The possible growth mechanism of Eu(OH)3 and Eu2O3 nanostructures is also discussed. The room-temperature photoluminescence analysis shows that Eu2O3 nanostructures have an intensive emission peak of Eu3+ ion at around 611 nm due to the 5D0–7F2 forced electric dipole transition of Eu3+ ions. It is found that the relative peak intensity increases with increasing reaction time.

Research highlightsIt is still very significant to develop a simple approach for large-scale synthesis of Eu(OH)3 and Eu2O3 nanostructured without the assistance of any added surfactant, catalyst or template under an ambient temperature. In this paper, a simple aqueous solution route was introduced for the fabrication of uniform Eu(OH)3 and Eu2O3 nanospindles, nanorods and nanobundles by using Eu(NO3)3 and NaOH as the starting reaction reagents at room temperature and atmosphere pressure without any surfactant and template. The influence of the molar ratios of [OH−]/[Eu3+], reaction time, and temperature was investigated. It is demonstrated that the size of Eu(OH)3 nanospindle can be well tuned by adjusting the [Eu3+]/[OH−] molar ratios. The possible growth mechanism of Eu(OH)3 and Eu2O3 nanostructures is also discussed. The room-temperature photoluminescence analysis shows that Eu2O3 nanostructures have an intensive emission peak of Eu3+ ion at around 611 nm due to the 5D0–7F2 forced electric dipole transition of Eu3+ ions. It is found that the relative peak intensity increases with increasing reaction time.