【摘要】 采用碳包埋方法制备了不同Eu²⁺掺杂浓度的七铝酸十二钙(C12A7∶x%Eu²⁺)导电荧光粉。在254 nm的紫外光激发下,样品呈现出位于444 nm的蓝光宽带发射峰,其来源于Eu²⁺的4f⁶5d¹-4f⁷跃迁。当Eu²⁺的掺杂浓度为1.0%时,蓝光发射强度最大。通过漫反射吸收光谱结合经验公式可计算C12A7∶1.0%Eu²⁺粉末样品的困陷于笼中的电子浓度为3.40×10¹⁹ cm^-3。在空气气氛下对C12A7∶1.0%Eu²⁺样品进行热处理,通过减少困陷于笼中的电子浓度,即增加困陷于笼中的O^2-离子浓度,可进一步提高样品的发光强度。阴极射线发光实验结果表明:铕掺杂七铝酸十二钙蓝光发射导电荧光粉在低压场发射显示器件中有潜在的应用前景。更多还原

【Abstract】 Eu²⁺ doped 12 CaO·7 Al₂O₃(C12 A7∶x% Eu²⁺) conductive phosphors with different concentrations were synthesized by a melting solidification method. Upon 254 nm UV excitation, we can observe a broad blue emitting band peaked at 444 nm, which originates from the 4 f⁶5 d¹-4 f⁷ transition of Eu²⁺. As the Eu²⁺ doping concentration is 1.0%, the strongest emission intensity can be achieved. The conductive performance of Eu²⁺ doped 12 CaO·7 Al₂O₃ phosphors can be attributed to the generation of encaged electrons and the calculated encaged electron concentration is ～3.40×10¹⁹ cm^-3. After the conductive phosphor was annealed in air, its photoluminescence intensity increased with increasing the amount of encaged O^2- anions（i.e. decreasing the amount of encaged electrons）. Our results suggest that C12 A7∶Eu²⁺ blue emitting conductive phosphors have a potential application in field emission displays.更多还原