New visible-light driven plasmonic photocatalysts

Rémi Dessapt (MC), Hélène Serier-Brault (MC), Stéphane Jobic (DR), Khadija Hakouk (PhD student)

Ag@metal-oxide semiconductor hybrid nanostructures are plasmonic photocatalysts which combine the localized surface plasmon resonance of the silver metal nanoparticles (NPs) with photoinduced electron transfers into the metal oxide. These materials are of great interest in visible-light induced water splitting, pollutant destruction and bacterial disinfection.We develop a new strategy for the synthesis of plasmonic nanostructures by an « all solid-state » photodeposition method from photoresponsive silver polyoxometalates. The 1D nanocomposite Ag@Ag₂Mo₃O₁₀^.2H₂O (Figure 1) is in-situ elaborated by exposing Ag₂Mo₃O₁₀∙2H₂O ultrathin nanowires under a low-power UV irradiation. Quasi spherical silver metal NPs with an average diameter around 10 nm are photogenerated at the surface of the semiconductor according to a mechanism which implies the concomitant reduction of Ag⁺ and Mo⁶⁺ ions. This novel approach is a promising alternative to classical photodeposition methods involving solid-liquid interfaces.

Figure 1 (a) MET image of the hybrid nanostructure Ag@Ag<sub<; a="">>2Mo₃O₁₀•2H₂O. (B) Characterization of metallic silver nanoparticles (red)
And Ag₂Mo₃O₁₀•2H₂O (blue) nanowires by electron energy loss spectroscopy (EELS). (C) Photocatalytic activity of the nanocomposite
Ag@Ag<sub<a ="" >>2Mo₃O₁₀•2H₂O in the visible during degradation of Rhodamine B in aqueous solution.

Involved people

Rémi Dessapt (MC), Hélène Serier-Brault (MC), Stéphane Jobic (DR)

Defended PhD thesis

Khadija Hakouk, Synthèse, caractérisation et photo-réactivité de polyoxométallates inorganiques et hybrides organique-inorganique, thèse soutenue le 5 décembre 2013

Publications

Novel Soft-Chemistry Route of Ag₂Mo₃O₁₀•2H₂O Nanowires and In Situ Photogeneration of a Ag@Ag<sub< a="">>2Mo₃O₁₀•2H₂O Plasmonic Heterostructure
K. Hakouk, P. Deniard, L. Lajaunie, C. Guillot-Deudon, S. Harel, Z. Wang, B. Huang, H.-J. Koo, M.-H. Whangbo, S. Jobic, R. Dessapt, Inorg. Chem., 52, 6440 (2013)

collaborations

Baibiao Huang, Zeyan Wang, State Key Lab of Crystal Materials, Shandong University, Jinan (China)
Hyun-Joo Koo, Department of Chemistry and Research Institute for Basic Sciences, Kyung Hee University, Seoul, Republic of Korea
Myung-Hwan Whangbo, Department of Chemistry, North Carolina State University, Raleigh (USA)