Anti-counterfeiting, latent fingerprint detection and optical thermometry using a multi-stimulus down-converting La2CaZnO5:Er3+ phosphor

Girisha, H.R.; Krushna, B.R. Radha; Lavanya, D.R.; Daruka, Prasad B; Sharma, S.C.; Nagabhushana, H.

doi:10.1016/j.optmat.2022.113053

Cited by 43 publications

(6 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For the analysis of PL properties, emission spectra were recorded at 372 nm excitation for all synthesized samples. The emission spectra exhibits characteristic green emission with peaks centred at 526 nm and 546 nm, corresponding to 2 H 11/2 → 4 I 15/2 and 4 S 3/2 → 4 I 15/2 transitions [22,48]. Notably, there was no change in peak profile with variation in doping concentration.…”

Section: Dmentioning

confidence: 95%

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Kumar,

Kumar

et al. 2024

IEEE Photonics J.

View full text Add to dashboard Cite

CaTiO 3 :xEr 3+ (0.1≤x≤7 mole %) phosphor materials were meticulously prepared through the solution combustion method. Comprehensive analyses employing Powder X-ray Diffraction (PXRD), Field Emission Scanning Electron Microscopy (FESEM), and Fourier Transform Infrared Spectroscopy (FTIR) were conducted to investigate the phase, morphology, and vibrational characteristics of the synthesized phosphors. A detailed luminescence study was undertaken using photoluminescence spectroscopy, revealing distinctive 4f-4f transitions associated with Er 3+ in both excitation and emission spectra. The application of Dexter's theory provided insights into the quenching mechanism inherent in CaTiO 3 :Er 3+ phosphors. Photometric studies were carried out to evaluate the suitability of the synthesized material for solid-state lighting applications. Furthermore, to assess the thermal stability of the phosphor material, the activation energy was computed. The fluorescence intensity ratio of thermally coupled energy levels of Er 3+ ion was utilized to assess the temperature-sensing capabilities of the synthesized material. This material may be suitable for solidstate lighting and optical thermometry applications. Index terms-Perovskite, Phosphor, solid-state lighting, and optical thermometry.

show abstract

Section: Dmentioning

confidence: 95%

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Kumar,

Kumar

et al. 2024

IEEE Photonics J.

View full text Add to dashboard Cite

show abstract

“…The obtained color purity is better than the previously reported surface-modified nanophosphors for La 2 Zr 2 O 7 :Ce 3+ with OA, La 2 Zr 2 O 7 :Eu 3+ with OA, and K 2 SiF 6 :Mn 4+ with OA. 11,12,34 The LZO:3Er 3+ @OA NPs demonstrate the highest color purity, making them particularly promising for applications that require superior color quality.…”

Section: Photometric Propertiesmentioning

confidence: 99%

“…Methods incorporating fatty acids like oleic acid (OA) to modify phosphors are being developed to improve latent print detection over traditional, less sensitive methods like powder dusting. 11 Luminescent materials modified with EDTA are advantageous for binding to amino acids and grease typically found in latent prints at crime scenes. Beyond fingerprints and cheiloscopy, the analysis of the unique patterns of lip prints provides auxiliary identification and is gaining importance in forensics.…”

Section: Introductionmentioning

confidence: 99%

Enhanced Down-Conversion Emission, High-Level Security, and Advanced Latent Fingerprint Visualization in La₂Zr₂O₇:Er³⁺ Nanophosphor through Surface Modification and Deep Learning Analysis

Lavanya,

Krushna,

Manjunatha

et al. 2024

ACS Appl. Opt. Mater.

View full text Add to dashboard Cite

This study explores surface modifications on Er 3+ -activated La 2 Zr 2 O 7 nanophosphors (NPs) through solution combustion, revealing a narrower band gap (3.1 eV) in surface-modified NPs. Under UV excitation (378 nm), these nanophosphors emit green light at 550 nm, notably enhanced by oleic acid (OA) modification, offering the potential for white light-emitting diode applications. Due to enhanced energy transfer processes, OA-modified NPs show 98.6% color purity and improved quantum efficiency (68.7%). Additionally, OA-modified NPs exhibit promise for UV-based forensic applications. This research also showcases the YOLOv8 algorithm's robustness (mAP@50 of 0.78 for bifurcation, 0.72 for ridge-end) in fingerprint detection, aiding forensics. The deep learning method supports feature-matching fingerprint detection and advanced identification techniques. These findings offer insights into nanophosphor modification's optical impact and advanced fingerprint identification methods, contributing to lighting technology and forensic applications.

show abstract

“…Over the years, counterfeiting and forgery of significant products and documents, including certificates, money, well-known brands, medications, cuisines, etc., is a significant threat that severely affects humans, the global economy, and social development worldwide. To solve these issues, many fluorescent-based materials have been used in AC applications; moreover, toxicity, spectral overlap, low quantum efficiency, and luminescence quenching still need to be solved . We prepared luminescence-based security inks to test the feasibility of the produced NPs for AC applications.…”

Section: Applicationsmentioning

confidence: 99%

Orange–Red Emitting Sr₉Al₆O₁₈:Pr³⁺ Nanophosphors for Advanced Latent Fingerprints and Security Ink

Swathi,

Krushna,

Manjunatha

et al. 2023

ACS Appl. Nano Mater.

View full text Add to dashboard Cite

This study presents the synthesis of orange–red emitting Sr9Al6O18:Pr3+ nanophosphors (SAO:Pr3+ NPs) through the solution combustion process. Photoluminescence (PL) spectra revealed concentration quenching at 5 mol % with a critical distance of R C = 21.5 Å, indicating that electric multipolar interactions are responsible for the nonradiative energy transfer in the SAO lattice. Dexter’s theory confirmed the quadruple–quadruple interaction as the mechanism behind the quenching. The optimized SAO:5Pr3+ NPs exhibited exceptional properties, including high color purity (CP = 94.2%), cost-effectiveness, eco-friendliness, scalability, and photostability. A fluorescence-based technique was developed using powder dusting to apply latent fingerprint (LFP) visualization and preservation. This method demonstrated high sensitivity, contrast, and no background interference, enabling the detection of LFPs over extended periods. Furthermore, lip prints (LPs), known for their sex differences and stability, have been effectively utilized for reliable and efficient forensic investigations. An unclonable invisible security ink was developed to combat counterfeiting, exhibiting high stability against UV light, aging, and physical abrasion. Mathematical models were employed for various fingerprint image processing tasks, including segmentation, normalization, ridge orientation estimation, ridge frequency estimation, Gabor filtering, binarization, thinning, and minutiae extraction. These algorithms were implemented by using a Python-based environment, resulting in enhanced fingerprints that displayed level I–II features. These findings underscore the potential applications of SAO:Pr3+ NPs in advanced forensic science and data security. This study offers insights into the synthesis, characterization, and application of SAO:Pr3+ NPs, highlighting their suitability for advanced forensic investigations, data security, and anticounterfeiting measures.

show abstract

Anti-counterfeiting, latent fingerprint detection and optical thermometry using a multi-stimulus down-converting La2CaZnO5:Er3+ phosphor

Cited by 43 publications

References 43 publications

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Enhanced Down-Conversion Emission, High-Level Security, and Advanced Latent Fingerprint Visualization in La₂Zr₂O₇:Er³⁺ Nanophosphor through Surface Modification and Deep Learning Analysis

Orange–Red Emitting Sr₉Al₆O₁₈:Pr³⁺ Nanophosphors for Advanced Latent Fingerprints and Security Ink

Contact Info

Product

Resources

About

Anti-counterfeiting, latent fingerprint detection and optical thermometry using a multi-stimulus down-converting La2CaZnO5:Er3+ phosphor

Cited by 43 publications

References 43 publications

Green Emission in Thermally Stable Er3+ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Green Emission in Thermally Stable Er3+ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Enhanced Down-Conversion Emission, High-Level Security, and Advanced Latent Fingerprint Visualization in La2Zr2O7:Er3+ Nanophosphor through Surface Modification and Deep Learning Analysis

Orange–Red Emitting Sr9Al6O18:Pr3+ Nanophosphors for Advanced Latent Fingerprints and Security Ink

Contact Info

Product

Resources

About

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Green Emission in Thermally Stable Er³⁺ Doped Lead-Free Perovskite Phosphor for Solid-State Lighting and Optical Thermometry Applications

Enhanced Down-Conversion Emission, High-Level Security, and Advanced Latent Fingerprint Visualization in La₂Zr₂O₇:Er³⁺ Nanophosphor through Surface Modification and Deep Learning Analysis

Orange–Red Emitting Sr₉Al₆O₁₈:Pr³⁺ Nanophosphors for Advanced Latent Fingerprints and Security Ink