Latent fingermarks detection for La2O3:Er3+/Yb3+ phosphor material in upconversion emission mode: A comparative study

Abstract

The authors in this manuscript present the results on synthesis of Er3+/Yb3+ codoped La2O3 upconverting phosphor and its demonstration on the development of latent fingermarks on the surfaces of semi-porous and non-porous objects. The samples were synthesized via combustion using urea as a reducing agent and chemical precipitation methods. The annealed samples showed enough intense green emission in the 520–550 nm range on 980 nm excitation. Excellent emission property of the samples in the green region showed an advantage to use it in latent fingermarks detection. A dry powder dusting technique is used to develop latent fingermarks and the results are compared. The studies reflected the superiority of upconversion phosphor materials for the detection of latent fingermarks over the traditional downconversion luminescence methods.

Nanoparticles used for fingermark detection—A comprehensive review

“…In another paper, Timari et al used silver NPs doped with La 2 O 3 :Yb,Er and applied this to marble stone. They observed that the NPs doped with 1.0 mw% of silver oxide gave clearer image compared to the NPs without any doping (Tiwari et al, ). Chen et al used red and white emitting LaVO 4 :Eu and LaVO 4 :Dy and observed good ridge detail on all the surfaces tested without background interference (C. Chen et al, ).…”

“…In another paper, Timari et al used silver NPs doped with La 2 O 3 :Yb,Er and applied this to marble stone. They observed that the NPs doped with 1.0 mw% of silver oxide gave clearer image compared to the NPs without any doping (Tiwari et al, 2015). Chen et al used…”

Recent Trends Concerning Upconversion Nanoparticles and Near-IR Emissive Lanthanide Materials in the Context of Forensic Applications

“…Progress to this effect has been highlighted in an extensive review by Bécue. [81] These nanomaterials have encompassed heavy-metal-based quantum dots (QDs), [82][83][84] noble-metal nanocomposites, [85] lanthanidebased phosphors (see below), [54,57,[86][87][88][89][90][91] and many others.…”

Commercial Upconversion Phosphors with High Light Harvesting: A Superior Candidate for High‐Performance Dye‐Sensitized Solar Cells

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