Investigation of energy transfer and concentration quenching of Dy3+ luminescence in Gd(BO2)3 by means of fluorescence dynamics

• Lifetime of Gd decreases with Dy concentration, confirming energy transfer.
• Rise time confirms the feeding of the Dy excited state by energy transfer.
• Concentration quenching of Dy emission is ascribed to resonant cross-relaxation.
• Interaction between Dy ions is dipole-dipole type through fitting with I-H model.

In this paper, the photoluminescence (PL) properties of Dy3+ activated Gd(BO2)3 phosphors are presented by means of fluorescence dynamics excited by pulsed laser light (λ = 266 nm). Energy transfer from Gd3+ to Dy3+ and concentration quenching of the Dy3+ luminescence are studied. From the PL spectra and decay curves the energy transfer from Gd3+ to Dy3+ is confirmed. The decay curves of Dy3+4F9/2 → 6H13/2 transition exhibiting build-up and decay process confirm the energy transfer between Gd3+ to Dy3+. The rise time becomes shorter as the Dy3+ concentration increases. The theoretical luminescence decay curves of (Gd1−xDyx) (BO2)3 samples agree well with the experimental observations. The concentration quenching of the Dy3+ ion emission can be ascribed to resonant cross-relaxation. The interaction between the Dy3+ ions is probably of the electric dipole–dipole type through fitting the data with Inokuti–Hirayama (I–H) model. The energy transfer parameters and critical distance for the transfer processes are given.