<mml:math display="inline"><mml:mrow><mml:mi mathvariant="normal">Ca</mml:mi><mml:msub><mml:mi mathvariant="normal">La</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:mi mathvariant="normal">Mo</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>:</mml:mo><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>,</mml:mo><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>CaLa2(MoO4)4:Sm3+,Eu3+ phosphors are prepared using a convenient solid-state reaction route. The red emission intensity of <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Eu3+ is enhanced by <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Sm3+ ion codoping. The energy transfer mechanism from <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Sm3+ to <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Eu3+ was found to be a dipole-quadrupole interaction with a critical distance of <mml:math display="inline"><mml:mrow><mml:mn>10.42</mml:mn><mml:mspace width="0.3em"></mml:mspace><mml:mi mathvariant="normal">Å</mml:mi></mml:mrow></mml:math>10.42Å . With increasing <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Eu3+ doping content, the energy transfer efficiency <mml:math display="inline"><mml:mrow><mml:mo>(</mml:mo><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>→</mml:mo><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>)</mml:mo></mml:mrow></mml:math>(Sm3+→Eu3+) gradually increased to 75.5%. The thermal quenching behavior was investigated using absorption and emission spectra. The thermal quenching temperature <mml:math display="inline"><mml:mrow><mml:mo>(</mml:mo><mml:msub><mml:mi mathvariant="normal">T</mml:mi><mml:mrow><mml:mn>50</mml:mn></mml:mrow></mml:msub><mml:mo>)</mml:mo></mml:mrow></mml:math>(T50) of <mml:math display="inline"><mml:mrow><mml:mi mathvariant="normal">Ca</mml:mi><mml:msub><mml:mi mathvariant="normal">La</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:mi mathvariant="normal">Mo</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>:</mml:mo><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>,</mml:mo><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>CaLa2(MoO4)4:Sm3+,Eu3+ phosphors is above <mml:math display="inline"><mml:mrow><mml:mn>200</mml:mn><mml:mo>°</mml:mo><mml:mi mathvariant="normal">C</mml:mi></mml:mrow></mml:math>200°C , and the activation energy of the thermal quenching process is <mml:math display="inline"><mml:mrow><mml:mn>0.13</mml:mn><mml:mspace width="0.3em"></mml:mspace><mml:mi>eV</mml:mi></mml:mrow></mml:math>0.13eV . The effect of codoped <mml:math display="inline"><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:math>Sm3+ ions on the thermal stability of <mml:math display="inline"><mml:mrow><mml:mi mathvariant="normal">Ca</mml:mi><mml:msub><mml:mi mathvariant="normal">La</mml:mi><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mo>(</mml:mo><mml:mi mathvariant="normal">Mo</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>)</mml:mo></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub><mml:mo>:</mml:mo><mml:msup><mml:mi mathvariant="normal">Sm</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>,</mml:mo><mml:msup><mml:mi mathvariant="normal">Eu</mml:mi><mml:mrow><mml:mn>3</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>CaLa2(MoO4)4:Sm3+,Eu3+ phosphors is investigated.

SrSi₂O₂N₂: Eu₂₊ green phosphors are prepared using a convenient solid-state reaction with Sr₂SiO₄: Eu₂₊ as the precursor. The activation energy of crystallization, electron-phonon coupling, and thermal quenching behavior are investigated using differential thermal analysis (DTA) spectra and photoluminescence measurements. SrSi₂O₂N₂: Eu₂₊ green phosphors exhibit excellent thermal stability and color stability due to their weak electron-phonon coupling strength (Huang-Rhys factor = 4.2). The thermal quenching temperature (T ₅₀) of SrSi₂O₂N₂: Eu₂₊ is above 200 °C. Results show that SrSi₂O₂N₂: Eu₂₊ green phosphors have a broad excitation band and good thermal stability, making them suitable for use in solid-state lighting and GaAsAl solar cells.

This study developed a hydrothermal method for the growth of three types of zinc oxide (ZnO) nanostructures: nanorods, nanowalls and nanoflowers. The structures are produced at high densities with a high degree of uniformity on Al-coated SiO₂ substrates without the need for surfactant. Unlike the random distribution of ZnO nanoflowers reported in previous studies, the proposed method makes it possible to control the distribution of these structures along the grooves created by altering the growth rate of ZnO nanorods and nanowalls. The number of ZnO nanoflowers created in this manner depends on the concentration of solution (HMT: hexamethylenetetramine) and reaction time. Measurements of cathodoluminescence (CL), X-ray diffractometry (XRD), and SEM-EDS confirm that the resulting structures are pure ZnO with good crystallinity. We also investigated the optical properties of these ZnO nanostructures and propose a possible growth mechanism.