Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3...Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3+)phosphors with 648 nm red emission,which belongs to the ^(4)G_(5/2)→^(6)H_(9/2) leap of Sm^(3+)and is close to the absorption wavelengths of plant chloro phylls and photochromes PR,were prepared by the high-temperature solid-phase method.The lattice mismatch between Sm^(3+)and Ca^(2+)is solved by cation substitution,which increases the atomic disorder and lattice distortion,and the lattice distortion also causes the forbidden leap to be disrupted,thus improving the luminescence efficiency.Meanwhile,the substitution of small-radius cations leads to the enhancement of the structural rigidity of the material.The test results show that after the introduction of Ca^(2+),the luminous intensity of the phosphor is increased by 5.15 times,the quantum yield is increased from 22.89%to 48.31%,and the I_(423 K)/I_(298 K) value is increased from 70.7%to 73.4%,and the fluorescence lifetime is also improved accordingly.White light-emitting diodes(WLEDs)and fuchsia light-emitting diodes(LEDs)were successfully prepared using the experimentally prepared phosphors,demonstrating their great potential in the fields of optical thermometers,WLEDs and plant growth.展开更多
Er^(3+)-doped BaLaGaO_(4)green phosphors was synthesized through a high-temperature solid-state reaction technique.The phase structure and morphology test results of the phosphor indicate that the BaLaGaO_(4)material ...Er^(3+)-doped BaLaGaO_(4)green phosphors was synthesized through a high-temperature solid-state reaction technique.The phase structure and morphology test results of the phosphor indicate that the BaLaGaO_(4)material was successfully synthesized and Er^(3+)ions were successfully doped into the main lattice.This doping does change the basic structure of the crystal.BaLaGaO_(4):Er^(3+)phosphor exhibits bright green emission centered at 545 nm when excited by 381 nm ultraviolet light or 980 nm near-infrared light.The optimal doping concentration is found to be x=0.04.To quantify the temperature sensitivity of the phosphor,the fluorescence intensity ratio method was used.Within the temperature range of 298-473 K,the maximum relative sensitivities are 1.35%/K(298 K,381 nm)and 1.45%/K(298 K,980 nm),respectively.The maximum absolute sensitivities are 0.67%/K(473 K,381 nm)and 0.69%/K(473 K,980 nm),respectively.Finally,white light-emitting diodes(WLEDs)with a high colour index of Ra=82and a relatively low correlated colour temperature of CCT=5064 K are obtained by integrating the synthesized BaLaGaO_(4):0.04Er^(3+)green phosphor into warm WLEDs devices.These results suggest that Er^(3+)-activated BaLaGaO_(4)multifunctional phosphors hold considerable promise in the areas of optical temperature sensing and WLEDs phosphor conversion.展开更多
基金Project supported by the National Natural Science Foundation of China(52403403)Guizhou Provincial Basic Research Program(Natural Science)(Qian ke he ji chu-ZK 20242024 YiBan 095)。
文摘Although significant progress has been made in the development of red phosphors,the development of efficient and thermally stable red phosphors remains a challenge.In this paper,(Sr_(3-y)Cay)Ca_(1-x)Nb_(2)O_(9):xSm^(3+)phosphors with 648 nm red emission,which belongs to the ^(4)G_(5/2)→^(6)H_(9/2) leap of Sm^(3+)and is close to the absorption wavelengths of plant chloro phylls and photochromes PR,were prepared by the high-temperature solid-phase method.The lattice mismatch between Sm^(3+)and Ca^(2+)is solved by cation substitution,which increases the atomic disorder and lattice distortion,and the lattice distortion also causes the forbidden leap to be disrupted,thus improving the luminescence efficiency.Meanwhile,the substitution of small-radius cations leads to the enhancement of the structural rigidity of the material.The test results show that after the introduction of Ca^(2+),the luminous intensity of the phosphor is increased by 5.15 times,the quantum yield is increased from 22.89%to 48.31%,and the I_(423 K)/I_(298 K) value is increased from 70.7%to 73.4%,and the fluorescence lifetime is also improved accordingly.White light-emitting diodes(WLEDs)and fuchsia light-emitting diodes(LEDs)were successfully prepared using the experimentally prepared phosphors,demonstrating their great potential in the fields of optical thermometers,WLEDs and plant growth.
基金supported by the National Natural Science Foundation of China(52403403)Guizhou Provincial Basic Research Program(Natural Science)(Qian ke he ji chu-ZK2024 YiBan 095)。
文摘Er^(3+)-doped BaLaGaO_(4)green phosphors was synthesized through a high-temperature solid-state reaction technique.The phase structure and morphology test results of the phosphor indicate that the BaLaGaO_(4)material was successfully synthesized and Er^(3+)ions were successfully doped into the main lattice.This doping does change the basic structure of the crystal.BaLaGaO_(4):Er^(3+)phosphor exhibits bright green emission centered at 545 nm when excited by 381 nm ultraviolet light or 980 nm near-infrared light.The optimal doping concentration is found to be x=0.04.To quantify the temperature sensitivity of the phosphor,the fluorescence intensity ratio method was used.Within the temperature range of 298-473 K,the maximum relative sensitivities are 1.35%/K(298 K,381 nm)and 1.45%/K(298 K,980 nm),respectively.The maximum absolute sensitivities are 0.67%/K(473 K,381 nm)and 0.69%/K(473 K,980 nm),respectively.Finally,white light-emitting diodes(WLEDs)with a high colour index of Ra=82and a relatively low correlated colour temperature of CCT=5064 K are obtained by integrating the synthesized BaLaGaO_(4):0.04Er^(3+)green phosphor into warm WLEDs devices.These results suggest that Er^(3+)-activated BaLaGaO_(4)multifunctional phosphors hold considerable promise in the areas of optical temperature sensing and WLEDs phosphor conversion.
