Stimuli-responsive color-tunable BaLa2ZnO5:Bi3+ phosphor for the encryption and authentication of security patterns and latent fingerprint detection

• Published in: Colloids and surfaces. A, Physicochemical and engineering aspects Physicochemical and engineering aspects, 2023-06, Vol.666, p.131219, Article 131219
• Main Authors: Girisha, H.R., Krushna, B.R. Radha, Manjunatha, K., Wu, Sheng Yun, Ho, Ming-Kang, Sharma, S.C., Prasad, B. Daruka, Subramanian, Balanehru, Kumar, J.B. Prasanna, Nagabhushana, H.
• Format: Article
• Language: English
• Subjects: Anti-counterfeiting; Latent finger print detection; Phosphor; Security ink; Stimuli-responsive
• ISSN: 0927-7757; 1873-4359
• DOI: 10.1016/j.colsurfa.2023.131219

Due to the outstanding optical qualities, stimulation-responsive luminous materials have drawn a lot of attention in the anti-counterfeiting application. In this work, the feasibility of applying BaLa2ZnO5:Bi3+ (BLZO:Bi3+) (0.5–4.0 mol%) phosphor, to multiple stimuli anti-counterfeiting (AC) and latent fingerprint visualization (LFP) is explored and discussed. The prepared luminous security ink from the optimized phosphor is effectively used for the multiple stimuli AC under 325, 355 and 375 nm excitation wavelengths. The results show that the fabricated luminous security ink is highly stable in ultraviolet (UV) light, various chemical environments, and ambient conditions. In addition, powder dusting method is utilized for LFPs detection on porous, non-porous and semi-porous surfaces under different excitation wavelengths. The multilevel features of the phosphor-attached LFP could be identified clearly in all the surfaces. The high-resolution LFPs imaging by scanning electron microscope (SEM) pictures, providing us more precise details on the width, distance, distribution, and forms of fingerprint (FP) pores. All the results reveal that the phosphor is a good potential choice for AC and LFP detection. [Display omitted] •At excitation wavelengths of 325, 355, and 375 nm, the BLZO:Bi3+ phosphor can produce blue, baby blue, and blue-green light.•latent fingerprints clearly captured by using the optimized phosphor in powder dusting method.•The application of the prepared luminous security ink for multiple stimuli anti-counterfeiting has been effectively proven.•Results show that luminous security ink is highly stable in UV light, various chemical environments, and ambient conditions.