White or tunable photoluminescence of phosphors is of great significance for their practical applications in the light-emitting diodes. In this work, Ba 2 Y(BO 3 ) 2 Cl:Bi 3+ ,Eu 3+ phosphors were fabricated, and their photoluminescence properties were investigated. Three difference luminescence peaks located at 366, 410, and 490 nm were observed in the single Bi 3+ -doped Ba 2 Y(BO 3 ) 2 Cl phosphor under the excitation of ultraviolet light attributed to three various Bi 3+ sites occupied in the Ba 2 Y(BO 3 ) 2 Cl host. By tuning the excitation wavelength from three various Bi 3+ sites, the tunable luminescence properties were obtained. The energy transfer from Bi 3+ at various sites to Eu 3+ were observed in the Ba 2 Y(BO 3 ) 2 Cl:Bi 3+ ,Eu 3+ phosphors by an electric dipole−dipole interaction. The tunable and white luminescence was obtained by changing the Eu 3+ concentration or excitation wavelength. The light-emitting diodes with the white light emission were constructed by coupling Bi 3+ and Eu 3+ codoped Ba 2 Y(BO 3 ) 2 Cl phosphors with the UV chip, which indicated that the Bi 3+ and Eu 3+ codoped Ba 2 Y(BO 3 ) 2 Cl phosphors can act as a promising candidate for the UV converted WLEDs.

We obtained upconversion (UC) light-emitting photonic materials (YbPO(4):Er) with an inverse opal structure by the self-assembly technique in combination with a solgel method. The effect of the photonic stopband on the UC luminescence of the (2)H(11/2), (4)S(3/2)→(4)I(15/2), and (4)F(9/2)→(4)I(15/2) transitions of Er(3+) has been observed in the inverse opals of the Er(3+)-doped YbPO(4). Significant suppression of the UC emission was detected if the photonic bandgap overlapped with the Er(3+) ions emission band, while enhancement of the UC emission occurs if the emission band appears at the edge of the bandgap.

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