Low temperature synthesis and SERS application of silver molybdenum oxides

Abstract

nanomaterials are synthesized at relatively low temperature (80 C) and with a short hydrothermal treatment time (3 h) using glucose (Glc) as a catalyst. Contrary to previous studies, it is possible to synthesize one of the Ag x Mo y O z binaries at 80 C by altering the pH of the reaction media in the presence of glucose. In addition, further experiments indicate that Ag/h-MoO 3 , Ag 2 Mo 2 O 7 and Ag/b-MoO 3 can be convertedto Ag/a-MoO 3 which can also be synthesized from a reaction involving ammonium heptamolybdate tetrahydrate and AgNO 3 at room temperature using cysteamine in both methods. Characterization with UV-Vis, XRD and Raman spectroscopy reveals high purity of as-synthesized product. These synthesized products are finally used to fabricate SERS substrates by coating a silicon wafer with a mixture of silver nanoparticles (Ag NPs) and Ag x Mo y O z (Si@Ag/Ag x Mo y O z ). The results show a good sensitivity and stability. In addition, it is also found that the SERS activity of Si

Surface‐enhanced Raman scattering characteristics of CuO : Mn/Ag heterojunction probed by methyl orange: effect of Mn2+ doping

“…[13][14][15][16][17] Recently, hybridization of nanoparticles of noble metals, e.g., Ag, Au, Cu and Pt with semiconductor, structured carbon and magnetic nanomaterials has drawn attention because of their outstanding SERS performance. [18][19][20][21][22][23][24][25][26] Because the optical band gap plays a crucial role in SERS, therefore, the tuning of the absorption band by doping, change in size, etc. is significance for SERS.…”

Three-dimensional SERS hot spots for chemical sensing: Towards developing a practical analyzer

“…More hotspots in terms of absolute numbers being available in a 3D space will certainly help to transform SERS into a practical analytical technique. To address the issues on 3D geometry of hotspots, various surfactants, DNA, peptide, DNA origami [10], amphiphilic polymers, or even proteins have been used to construct 'fixed' hotspots on solid substrates by preparing oriented assemblies of functional NPs, such as SHINERS [11], core-shell monomers [12], dimers [13,14], trimers [15], chains [16], arrays [17,18], aggregates [19,20], or even multilevel structures [21,22]. On the other side, 'flexible' designs utilizing electronic, ferroelectric, thermal, mechanical strain, or capillary effects have allowed for the tunability of 3D plasmonic hotspots.…”

Experimental and Theoretical Investigations of Electronic Structure and Photoluminescence Properties of β-Ag2MoO4 Microcrystals

“…Singh et al 11 investigated the influence of pH on the formation of broom-and flowerlike Ag 2 MoO 4 heterostructures by the CH approach. In another report, Fodjo et al 25 used the borohydride reduction reaction to prepare Ag 2 MoO 4 nanoparticles for applications in surface-enhanced Raman scattering activities. Also, published studies 12,26 have shown that Ag−Ag 2 MoO 4 composites exhibit good photocatalytic activity under visiblelight irradiation for the degradation of Rhodamine B as well as graphite/Ag 2 MoO 4 lubricants in Ni-based composites to improve tribological properties, preventing the high-friction and wear.…”

“…In addition, morphological aspects are able to dislocate crystal lattice planes as well as adjacent particles in aggregates, producing defects in the crystals. In another study, 25 the PL properties of Ag 2 MoO 4 crystals were attributed to chargetransfer transitions in the anion molecular complex. However, in our previous research 57 …”