Remarkable fluorescence enhancement in YVO4:Eu3+@Ag nano-hybrids induced by interface effect

The luminescence enhancement effect induced by the coupling of noble metal nanoparticles (NPs) with rare earth (RE) doped nanophosphors is attracting current interests. In order to obtain efficient luminescence enhancement and clarify its physical nature, the YVO4:Eu3+@Ag core-shell nano-hybrids colloids were first prepared by a facile two-step seed-mediated growth method. The luminescence enhancement of 5D0–7FJ transition for Eu3+ with a maximal factor of ∼one order was observed, which strongly depended on the amount of silver NPs, the concentration of the YVO4:Eu3+ colloids and the dissolved solutions. The enhancement mechanism was carefully discussed based on absorption spectra, emission spectra, luminescent decay dynamics and zeta potentials of colloids solutions. The results indicate that the silver NPs on the surface of YVO4:Eu3+ can effectively prevent VO43− and Eu3+ from the interaction with the solvent such as OH bonds, leading to a decrease of nonradiative energy transfer (ET) and suppressed luminescent quenching. A detailed model was proposed to explain the interesting luminescence enhancement behavior.