Effect of Bi3+ on fluorescence properties of YPO4:Dy3+ phosphors synthesized by a modified chemical co-precipitation method

► YPO4:Dy3+, Bi3+ was synthesized by chemical precipitation method using urea as pH value regulator. ► Bi3+ can improve the luminescent efficiency of YPO4:Dy3+. ► The phosphor has a broad excitation band from 250-400 nm including peaks at 294, 326, 352 and 365 nm. ► The yellow-to-blue emission intensity ratio is related to the excitation wavelength not Bi3+.