SiO 2 @LaOF:Eu 3+ core-shell functional nanomaterials for sensitive visualization of latent fingerprints and WLED applications
2018
Abstract For the first time, intense red color composite of SiO 2 @LaOF:Eu 3+ core-shell nanostructures (NS) were fabricated via facile solvothermal method followed by thermal treatment. The obtained core–shell particles display better spherical shape and non-agglomeration with a narrow size distribution. Photoluminescence (PL) emission spectra exhibits intense peaks at ∼593 nm, 611 nm, 650 nm corresponds to 5 D 0 → 7 F J (J = 0, 1 and 2) Eu 3+ transitions respectively. The spectral intensity parameters and Eu-O ligand behaviors are estimated by means of Judd-Ofelt (J-O) theory. CIE co-ordinates are found to be (x = 0.63, y = 0.36) which is very close to standard NTSC values (x = 0.67, y = 0.33). CCT value is ∼3475 K which is less than 5000 K, as a result this phosphor is suitable for warm light emitting diodes. The optimized core-shell SiO 2 (coat III)@LaOF:Eu 3+ (5 mol%) was used as a fluorescent labeling marker for the visualization of latent fingerprints on both porous and non-porous surfaces. Obtained fingerprints are highly sensitive and selective also no background hindrance which enables level-I to level-III fingerprint ridge characteristics. Observed results indicate that the significant improvement in luminescence of coreshell NS can be explored as a sensitive functional nanopowder for advanced forensic and solid state lightning applications.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
51
References
39
Citations
NaN
KQI