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Ceria-zirconia-alumina composite oxides CZ + A(pm) and CZ + A(mm) (the molar ratio of Ce, Zr and Al was 1 = 1 = 2) were prepared by the mixing precursor of precipitates and the mixing precipitates mechanically methods, respectively. The samples were thermally aged in a flowing air atmosphere and in 10% H2/Ar flow. The structure and performance of the composite oxides were studied by X-ray diffraction (XRD), N2 adsorption-desorption (BET), oxygen storage capacity (OSC) measurements, and H2 temperature-programmed reduction (H2-TPR). The results show that the XRD patterns of CZ+A(pm)-H2-1 100 exhibited many sharp diffraction peaks attributed to CeAlO3, but CZ + A(mm)-H2-1 100 reductively aged at 1 100 °C did not appear CeAl()3phase. The oxygen storage capacity (OSC) was 157 and 773 µmol/g, respectively, which were far higher than the 23.2 µmol/g of CZA-H2-1 100, and the hydrogen consumption of H2-TPR was 960 and 1 916 µmol/g, respectively, while the hydrogen consumption of CZA-H2-1 100 was significantly reduced to 310 µmol/g. The OSC of CZ+A(pm) was affected by the formation of CeAlO3 during the reductive treatment, which was consistent with the change result of reductive performance. It was found that CeO2 and Al2O3 in CZ+A (pm) samples, with the particles of cerium-zirconium and alumina being small in scale and close in contact with each other, were more likely to produce CeAlO3 through solid-phase combination reaction. However, the reductive treatment of CZ+A(mm) samples, for the cerium-zirconium and alumina particles being larger and farther apart, could inhibit the formation of CeAlO3, thus significantly improving the oxygen storage performance and reductive performance of the material in the reduction atmosphere. [ABSTRACT FROM AUTHOR]

Thioglycolic acid-capped CdTeS quantum dots (QDs) were synthesized through a one-step approach in an aqueous medium. The CdTeS QDs played the role of a color conversion center. The structural and luminescent properties of the obtained CdTeS QDs were investigated. The fabricated red light-emitting hybrid device with the CdTeS QDs as the phosphor and a blue InGaN chip as the excitation source showed a good luminance. The Commission Internationale de L'Eclairage coordinates of the light-emitting diode (LED) at (0.66, 0.29) demonstrated a red LED. Results showed that CdTeS QDs can be excited by blue or near-UV regions. This feature presents CdTeS QDs with an advantage over wavelength converters for LEDs. [ABSTRACT FROM AUTHOR]

High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications.High-quality ZnSe:Eu, Mn quantum dots (QDs) with white light emitting were synthesized via a green preparation method in an aqueous solution using thioglycolic acid as a stabilizing agent. The composition of the QDs could be flexibly controlled by varying the amount of Eu or Mn cation. The effects of reflux time and Eu2+ ion dopant concentration on the luminescence properties were systematically investigated. The obtained QDs were characterized by photoluminescence spectrometry, X-ray powder diffraction, and high-resolution transmission electron microscopy. The proposed method formed cubic ZnSe:Mn2+, Eu2+ QDs with the maximum emission peak at 460 and 580 nm. In the optimal condition, the quantum yields of ZnSe:Mn2+, Eu2+ QDs could reach 27.68%. The CIE color coordinates were (0.328, 0.334), which agreed with those of pure white light (0.33, 0.33). The results verified that the ZnSe:Mn2+, Eu2+ QDs exhibited potential in light-emitting diode applications. [ABSTRACT FROM AUTHOR]