Silver sulfide nanoparticle assembly obtained by reacting an assembled silver nanoparticle template with hydrogen sulfide gas

Abstract

A fast, simple procedure is described for obtaining an assembly of silver sulfide nanoparticles (Ag(2)S NPs) on a glass substrate through reaction of a template of an assembled layer of silver nanoparticles (Ag NPs) with hydrogen sulfide (H(2)S) gas. The Ag NP template was prepared by assembling a monolayer of spherical Ag NPs (mean diameter of 7.4 nm) on a polyethylenimine-treated glass substrate. Exposure to pure H(2)S for 10 min converted the Ag NPs of the template to Ag(2)S NPs. The resulting Ag(2)S NP assembly, which retains the template nanostructure and particle distribution, was characterized by optical absorption spectroscopy, atomic force microscopy, transmission electron microscopy (TEM), scanning high resolution TEM, energy dispersive x-ray spectroscopy and x-ray photoelectron spectroscopy. The Ag(2)S NPs have a crystal structure of monoclinic acanthite, and while they retained the spherical shape of the original Ag NPs, their mean particle size increased to 8.4 nm due to changes to the crystal structure when the Ag NPs are converted into Ag(2)S NPs. The measured optical absorption edge of the Ag(2)S NP assembly indicated an indirect interband transition with a band gap energy of 1.71 eV. The Ag(2)S NP assembly absorbed light with wavelengths below 725 nm, and the absorbance increased monotonically toward the UV region.

Enhanced terahertz emission by coherent optical absorption in ultrathin semiconductor films on metals

“…However, we note that the enhancement of THz emission is not limited to the three semiconductors described in this paper. For example, we also observe fairly strong THz emission from thin films of silver sulfide (Ag 2 S), a semiconducting material [53], formed on silver (Ag) substrates. It might also be possible to have enhanced terahertz emission from thin films of GaAs or InAs of the right thicknesses deposited on metal surfaces.…”

Luminescence Enhancement Mechanism of Lanthanide-Doped Hybrid Nanostructures Decorated by Silver Nanocrystals

“…Because Si-O-H moieties are consumed when Si-O-C and Si-O-Ag are formed, the weak 957-cm −1 absorption peak attributed to the Si-O-H stretching vibration disappears gradually as Ag NP increases [35]. The appearance of the weak 1,558-cm −1 band ascribed to N-H bending possibly indicates an interaction -NH 2 group and Ag NPs [29,30].…”

“…Ag NP decoration was carried out using the coupling reaction of 3-aminopropyltriethoxysilane (KH-550) with LaF 3 :Yb 3+ , Er 3+ @SiO 2 nanostructure [29,30]. The LaF 3 :Yb 3+ , Er 3+ @SiO 2 nanostructure suspension was heated to 100°C in an oil bath, then 30 mL of an aqueous solution containing a quantity of AgNO 3 (as specified in Table 1) and 0.65 mL KH-550 were successively added to the solution with stirring.…”

The influence of the constituent elements on the corrosion mechanisms of silver alloys in sulphide environments: the case of sterling silver

“…This band can be ascribed to the formation of Ag 2 S particles, which size increases with the immersion time. 44 The band energy gap estimated for the 7 min sample is 1.1 eV that could correspond to the presence of Ag 2 S particles.…”

“…43 The sample immersed during 1 min has a broad band with a maximum absorption at 484 nm, which can be attributed to the nucleation of amorphous Ag 2 S with a particle size inferior to 10 nm. 44 The sample immersed during 3 min has a well-dened absorption band with a maximum at 528 nm, corresponding to an estimated band gap energy of 1.2 eV, value reported for both Ag 2 O and Ag 2 S band gap energies.…”