Good thermal dispersion is essential for phosphors used in laser-lighting applications. Luminescent films naturally show better thermal dispersion than bulk phosphor because the distance to the supporting substrate is shorter, which facilitates heat dissipation. However, the underlying mechanism for luminescence saturation in films is still unclear. In addition, the synthesis of luminescent films always involves the use of carbon-rich organic materials, which can introduce both pores and carbon residues. Here, we present a facile sol–gel route to synthesize YAG:Ce thick films suitable for laser lighting applications. Inorganic aluminum hydroxides are used as gelling agent, which solves the carbon residue problem. A series of YAG:Ce films of different thicknesses was produced at relatively low temperature (975 °C). The YAG:Ce film shows no luminescence saturation under 4.1 W blue laser excitation. This means this approach represents a strong potential candidate for applications like automotive headlamps and many other devices.

良好的热分散性对于激光照明应用中使用的磷光体至关重要。发光膜自然显示出比体荧光粉更好的热分散性，因为到支撑基板的距离更短，这有利于散热。但是，膜中发光饱和的潜在机理仍不清楚。另外，发光膜的合成总是涉及使用富含碳的有机材料，这会引入孔和碳残留物。在这里，我们提出了一种简便的溶胶-凝胶路线来合成适用于激光照明应用的YAG：Ce厚膜。无机氢氧化铝用作胶凝剂，解决了碳残留问题。在相对较低的温度（975°C）下生产了一系列不同厚度的YAG：Ce膜。YAG：Ce薄膜在4.1 W蓝色激光激发下未显示出发光饱和。这意味着该方法代表了汽车前照灯和许多其他设备等应用的强大潜力。