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We report the effect of temperature on the stability of glutathione-protected Ag 25 clusters. The clusters are stable up to 50 °C. Interestingly, above this temperature, they decompose to yield Ag 2 S nanoparticles with an average diameter of 3 ± 1 nm, crystallizing in monoclinic acanthite polymorph. Unlike conventional methods of syntheses of Ag 2 S, where a temperature of ∼200 °C is needed, our study shows the possibility of synthesis of Ag 2 S nanoparticles at much lower temperatures. This is in contrast with silver nanoparticles protected with thiolates, which typically give silver and alkyl/aryl disulfide upon thermal activation. The mechanism of cluster decomposition and formation of silver sulphide nanoparticles was investigated using various analytical techniques such as ultraviolet−visible spectroscopy, X-ray diffraction scanning electron microscopy, energy-dispersive analysis of X-rays, transmission electron microscopy, and electrospray ionization mass spectrometry. The monolayer of the cluster undergoes S−C bond cleavage, as revealed by mass spectrometry. This is somewhat unusual because Ag−S cleavage is expected in view of its lower bond energy.

The morphology of a nanoparticle strongly controls the path ofelectronic interaction, which directly correlates to the physicochemical properties and also the electrochemical comportment. Conjoining it with a two-dimensional (2D) material...

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Effect of the Yb dopant on the structural, magnetic, and electrical properties of the multiferroic BiFeO3 have been studied. The structural properties of sol-gel derived Bi1-xYbxFeO3 (x = 0.0, 0.1, and 0.2) nanoparticles reveal the formation of a rhombohedrally distorted perovskite in XRD and a reduction in the average grain size have been observed with an increase in the Yb concentration. Microstructural studies exhibited the formation of sphere like morphology with decreasing particle size with increase in the dopant concentration. The effective doping also resulted in larger magnetization as well as coercivity with the maximum of 257 Oe and 1.76 emu/g in the Bi0.8Yb0.2FeO3 nanoparticles. Ferroelectric as well as dielectric properties of the nanoparticles were also improved on doping. The best results were obtained for the BiFeO3 nanoparticles having Yb concentration x = 0.2.