Abstract Latent fingerprint detection is one of the promising technique in forensic science. Here, an oxide based red-emitting phosphors, CaGdAlO4:Eu3+ (CGA:Eu3+), have been successfully synthesized by a solvothermal reaction method. The structural phase was characterized with the XRD Rietveld refinement and TEM analyses. The luminescence properties and dynamics of Eu3+ in CGA were studied in detail by room temperature emission, excitation and decay curve measurements. Intense red emission peaking at 620 nm due to 5D0→7F2 transitions of Eu3+ under the excitation at 283 nm was obtained and the optimal Eu3+ ion concentration was found to be about 7 mol%. The CIE chromaticity coordinate evaluated from the PL spectra and exhibited (0.6410, 0.3581) coordinates within the pure red region of the CIE 1931 diagram with a close proximity to the commercial red phosphor (Y2O2S:Eu3+). Furthermore, with the use of the CGA:7Eu3+ phosphors, the developed latent fingerprint fluorescent images were well visualized and identified their level 1, 2 and 3 details with high contrast, selectivity and sensitivity. These results indicate that CGA:7Eu3+ has great potential for practical applications in the latent fingerprint detection.

中文翻译：

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用于潜在指纹检测的多功能荧光 CaGdAlO4:Eu3+ 红色磷光体

摘要 潜指纹检测是法医学中很有前景的技术之一。在这里，基于氧化物的红色荧光粉 CaGdAlO4:Eu3+ (CGA:Eu3+) 已通过溶剂热反应方法成功合成。用 XRD Rietveld 精修和 TEM 分析表征结构相。通过室温发射、激发和衰减曲线测量，详细研究了 CGA 中 Eu3+ 的发光特性和动力学。由于在 283 nm 激发下 Eu3+ 的 5D0→7F2 跃迁，在 620 nm 处获得了强烈的红色发射峰，发现最佳 Eu3+ 离子浓度约为 7 mol%。从 PL 光谱评估的 CIE 色度坐标显示 (0.6410, 0. 3581) 坐标在 CIE 1931 图的纯红色区域内，与商业红色磷光体 (Y2O2S:Eu3+) 非常接近。此外，通过使用 CGA:7Eu3+ 荧光粉，开发的潜指纹荧光图像可以很好地可视化，并以高对比度、选择性和灵敏度识别它们的 1、2 和 3 级细节。这些结果表明 CGA:7Eu3+ 在潜在指纹检测中具有巨大的实际应用潜力。