Synthesis of a new phosphor based on rare earth oxycarbonate

Synthesis of new red emitting phosphors based on rare earth oxycarbonates

“…These results suggest that Eu 3+ ions substituted the R 3+ (R = La, Gd, and Y) site whose symmetry is C 3v [3]. Although nominal amount of potassium (≤1 mol%) was identified by the X-ray fluorescence analysis, it have already been elucidated in our previous works that the luminescent properties of the oxycarbonate phosphors were not affected by the small amount of the flux remained in the samples [6,7].…”

“…As we previously indicated, it is possible to synthesize the highly crystalline type-II lanthanum oxycarbonate in a single phase using a simple flux method in atmospheric air, where alkaline metal carbonates are applied as the flux [5][6][7]. In this method, the type-II oxycarbonate can be obtained readily, just by heating a mixture of the flux and the precursor in a flow of 10%CO 2 -N 2 gas for 12 h. In the present study, we have successfully synthesized the type-II Eu 3+ -doped R 2 O 2 CO 3 (R = La, Gd, and Y) in a single phase by the flux method employing the 0.476Li 2 CO 3 -0.270Na 2 CO 3 -0.254K 2 CO 3 eutectic mixture, and their photoluminescence properties have been characterized.…”

Synthesis of new green emitting phosphors based on rare earth oxycarbonates

“…It should be noted that it becomes possible for the first time to synthesize the crystalline II-Y 2 O 2 CO 3 in a single phase by our flux method [11]. Although a small amount of potassium (<1 mol%) remained in the samples as detected by the X-ray fluorescence analysis, we have already elucidated in our previous works that the luminescent properties of the oxycarbonate phosphors are not affected by the nominal flux remained in the samples [9,10].…”

“…In our previous works, on the contrary, we have found a new synthesis route for preparing well-crystallized II-La 2 O 2 CO 3 in a single phase by a simple flux method using alkaline metal carbonates, and photoluminescence property of Tb 3+ -doped La 2 O 2 CO 3 was investigated [9,10] …”

Enhancement of the luminescent intensity of the green emitting Gd2O2CO3:Tb phosphor

“…The Eu 3+ -or Tb 3+ -doped II-RE 2 O 2 CO 3 (RE = La, Gd, and Y) phosphors prepared by our flux method showed high emission intensities despite that the particle size was in a submicron scale [6][7][8][9][10]. In the series of the oxycarbonate phosphors examined, II-Gd 2 O 2 CO 3 :17 at.%Tb 3+ exhibited the highest relative emission intensity, which was 101% of that of a commercial LaPO 4 :Ce 3+ ,Tb 3+ phosphor [8,9].…”