Preparation of Gold/Silver Core-Shell Nanoparticles for Colorimetric Sensing and as Photocatalyst in the Degradation of Organic Dye

Ai Chia Patrick Melet, Sheela Chandren, Wijitar Dungchai

Abstract


Bimetallic gold/silver core-shell nanoparticles (Au/Ag core-shell NPs) were prepared by chemical reduction in aqueous solution, using an environmental-friendly and economical method. Core Au NPs (~20 nm) were synthesized in the presence of citrate ions as the reducing agent and stabilizing agent. Synthesis of Ag shell was carried out by reducing Ag+ over Au sol in the presence of ascorbic acid (AA) as the reducing agent. Localized surface plasmon resonance (LSPR) of Au (~520 nm) obtained from ultraviolet-visible (UV-Vis) spectra, confirmed the formation of the NPs, while the formation of core-shell structure was proven by the presence of blue-shifting in the spectrum after the addition of AA into the Ag precursors. Transmission electron microscopy (TEM), field-emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD) analyses confirmed the presence of Au core and Ag shell in the core-shell structure. The synthesized Au/Ag core-shell NPs were utilized in the application of colorimetric sensing of Vitamin C (also known as AA) and photocatalytic degradation of an organic dye, methyl orange (MO). For colorimetric sensing, the distance-based paper sensor was designed to determine a high-resolution colorimetric protocol. Au/Ag core-shell NPs in solution form was used as the indicator on the sensor to detect AA, where the quantification of AA has been achieved by measuring the length of the yellow colour band, and it was shown that the yellow colour band length was proportional to the concentration of AA. In the photocatalytic degradation of MO, it was found that the Au/Ag core-shell NPs were inactive under visible light irradiation, contrary to the characterization results. This could be caused by the lower surface area of the agglomerated NPs and the change in the oxidation state of the metals. Hence, modification to the synthesis step must be undertaken in order to allow visible light photocatalytic activity.

Keywords


Gold nanoparticles; silver nanoparticles; core-shell; colorimetric sensing; photocatalytic

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References


Mody, V. V., Siwale, R., Singh, A., & Mody, H. R. Introduction to metallic nanoparticles. Journal of Pharmacy and Bioallied Sciences. 2(4) (2010) 282.

Katz, E., Baron, R., & Willner, I. Magnetoswitchable electrochemistry gated by alkyl-chain-functionalized magnetic nanoparticles: Control of diffusional and surface-confined electrochemical processes. Journal of the American Chemical Society. 127(11) (2005) 4060-4070.

Khan, I., Saeed, K., & Khan, I., Nanoparticles: Properties, applications and toxicities. Arabian Journal of Chemistry, (2017) 1-24.

Laurent, S., Forge, D., Port, M., Roch, A., Robic, C., Vander Elst, L., & Muller, R. N.. Magnetic iron oxide nanoparticles: synthesis, stabilization, vectorization, physicochemical characterizations, and biological applications. Chemical reviews. 108(6) (2018) 2064-2110.

Linic, S., Christopher, P., & Ingram, D. B. Plasmonic-metal nanostructures for efficient conversion of solar to chemical energy. Nature materials, 10(12) (2011) 911.

Huang, H., Huang, S., Yuan, S., Qu, C., Chen, Y., Xu, Z., Liao, B., Zeng, Y., & Chu, P. K. High-sensitivity biosensors fabricated by tailoring the localized surface plasmon resonance property of core–shell gold nanorods. Analytica chimica acta. 683(2) (2011) 242-247.

Stuchinskaya, T., Moreno, M., Cook, M. J., Edwards, D. R., & Russell, D. A. Targeted photodynamic therapy of breast cancer cells using antibody–phthalocyanine–gold nanoparticle conjugates. Photochemical & Photobiological Sciences. 10(5) (2011) 822-83

Singh, P., Thuy, N. T., Aoki, Y., Mott, D., & Maenosono, S. Intensification of surface enhanced Raman scattering of thiol-containing molecules using Ag@ Au core@ shell nanoparticles. Journal of Applied Physics. 109(9) (2011) 094301

Steinbrück, A., Stranik, O., Csaki, A., & Fritzsche, W. Sensoric potential of gold–silver core–shell nanoparticles. Analytical and bioanalytical chemistry. 401(4) (2011) 1241.

Ji, Y., Yang, S., Guo, S., Song, X., Ding, B., & Yang, Z. Bimetallic Ag/Au nanoparticles: A low temperature ripening strategy in aqueous solution. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 372(1-3) (2010) 204-209.

Haldar, K. K., Kundu, S., & Patra, A. Core-size-dependent catalytic properties of bimetallic Au/Ag core–shell nanoparticles. ACS applied materials & interfaces. 6(24) (2014) 21946-21953.

Calagua, A., Alarcon, H., Paraguay, F., & Rodriguez, J. Synthesis and characterization of bimetallic gold-silver core-shell nanoparticles: a green approach. Advances in Nanoparticles. 4(04) (2015) 116.

Zeng, J., Cao, Y., Lu, C.-H., Wang, X.-d., Wang, Q., Wen, C.-y., Qu, J.-B., Yuan, C., Yan, Z.-f., & Chen, X. A colorimetric assay for measuring iodide using Au@ Ag core–shell nanoparticles coupled with Cu2+. Analytica chimica acta. 891 (2015) 269-276.

Nandini, R., & Vishalakshi, B. A study of interaction of methyl orange with some polycations. Journal of Chemistry, 9(1) (2012) 1-14

Fu, C., Li, M., Li, H., Li, C., guo Wu, X., & Yang, B. Fabrication of Au nanoparticle/TiO2 hybrid films for photoelectrocatalytic degradation of methyl orange. Journal of alloys and compounds. 692 (2017) 727-733.


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