Silver Nanoparticle Films with Highly Tunable Plasmon Properties: Tuning the Plasmon Resonance Band for X-Ray Detection

Plasmon-enhanced luminescence is a powerful approach for enhancing many sensing technologies but appropriate tuning of the plasmon band with the excitation and/or emission band of the luminescent species remains a... [ view full abstract ]

• Plasmon-enhanced luminescence is a powerful approach for enhancing many sensing technologies but appropriate tuning of the plasmon band with the excitation and/or emission band of the luminescent species remains a challenge[1–3]. We developed a simple and fast microwave-assisted method to grow silver nanoparticle films with tunable plasmon resonance band. The plasmonic properties can be easily tuned by controlling the microwaving time and the number of deposition cycles. Films can be grown with microwaving times as short as 20 s.  Microwaving time of 30 s leads for films with a single well-defined plasmon resonance band (400 nm), whereas films produced with times longer than 40 s presented higher wavelength resonances modes, with at least two distinguishable plasmon resonance bands at 400 nm and 500 nm. The films were employed to enhance the sensitivity of x-ray detectors, which was assessed by the luminescence emitted from irradiated KCl crystals by Optically Stimulated Luminescence (OSL). By tuning the plasmon resonance band to overlap with the OSL stimulation (530 nm), luminescence enhancements of greater than 100-fold were obtained, demonstrating the importance of tuning the plasmon resonance band to maximize the OSL intensity and detector sensitivity. These findings reveal the versatility of the method developed here to produce silver nanoparticles films with tunable plasmonic properties, standing as promising platform for developing more sensitive, and miniaturized, radiation detectors as well as advanced sensing technologies involving plasmon enhanced luminescence and SERS.

References

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[2]       E.J. Guidelli, A.P. Ramos, O. Baffa, Optically Stimulated Luminescence Under Plasmon Resonance Conditions Enhances X-Ray Detection, Plasmonics. 9 (2014). doi:10.1007/s11468-014-9713-4.

[3]       E.J. Guidelli, A.P. Ramos, O. Baffa, Silver nanoparticle films for metal enhanced luminescence: Toward development of plasmonic radiation detectors for medical applications, Sensors Actuators, B Chem. 224 (2016). doi:10.1016/j.snb.2015.10.024.