Luminescence properties of Nd³⁺/Yb³⁺ co-doped yttrium silicate nanophosphors excited by at laser diode of 975 nm

Trivalent rare earth ions doped materials can convert near infrared photons to different visible emissions and Yb³⁺ rare earth ions have only two levels of ²F_7/2 and ²F_5/2 in the near infrared region. Yb³⁺ ions are generally used as sensitizer to obtain high emissions from other rare earths by using ∼975 nm laser and the near infrared photon energy can be transferred from Yb³⁺ to other ions. The energy level ⁴F_3/2 of Nd³⁺ is little higher than the ²F_5/2 level of Yb³⁺, so Nd³⁺ emission may be sensitized by energy transfer from Yb³⁺ ion. In this work, we studied the luminescence properties of Nd³⁺/Yb³⁺ co-doped yttrium silicate (Y₂O₃:SiO₂) nanopowder with a 975 nm diode laser excitation. The emission properties and spectral changes were analyzed at atmospheric pressure and vacuum. The decay and rise patterns were carried out under vacuum (0.01 mbar) and atmospheric pressures.