Improved trap capability of shallow traps of Sr2MgSi2O7:Eu2+,Dy3+ through depositing Au nanoparticles

Sr2MgSi2O7:Eu2+,Dy3+ (SED) is a common long afterglow luminescence material. Currently, to obtain excellent luminescence performance, researches mainly focused on the adjustment of defects and luminescence center in the matrix. However, due to concentration quenching, the desired effect is not achieved. In this study, a simple and economical method is proposed to improve the utilization of luminescence center and different traps in the matrix, Au nanoparticles (AuNP) are deposited on the surface of SED by photo-reduction deposition method for the first time. The surface morphology and state of Au/Sr2MgSi2O7:Eu2+,Dy3+ (Au/SED) are characterized by TEM and XPS. After depositing AuNP, the photo-excited emission intensity and afterglow luminescence (AfgL) performance of SED is improved and the AfgL intensity in the fast decay process of SED is increased about 50%, which results are mainly attributed to the surface plasma effect (SPE) of AuNP. Compared with SED, Au/SED produce a stronger emission under the excitation light of 600 nm visible light. In this paper, the surface plasma effect of AuNP is introduced into the long afterglow material SED for the first time and the enhancement mechanism Au/SED is discussed. •Au nanoparticles are successfully deposited on the surface of Sr2MgSi2O7:Eu2+,Dy3+.•The trap capability of shallow traps of Sr2MgSi2O7:Eu2+,Dy3+ is improved by surface plasmon effect.•The surface plasmon effect of AuNP is introduced into Sr2MgSi2O7:Eu2+,Dy3+.