The Role of Ammonia in Synthesis of Silver Nanoparticles in Skim Natural Rubber Latex

Abstract

Silver nanoparticles (AgNPs) were synthesized in skim natural rubber latex, the by-product from concentrated latex production. The role of ammonia was investigated by varying the concentration to be 0.217, 0.362, 0.377, 0.392, and 0.406 wt%. The emergence of AgNPs was detected by UV-visible spectrophotometer and electrical conductivity meter. Upon increasing ammonia concentration, the ABS peak increased to a maximum and slightly shifted to a higher wavelength and then it decreased afterward and slightly shifted to a lower wavelength. The shift of the ABS peak was consistent with the conductivity result. The kinetic model was proposed to explain the competition between the reducing effect and size-controlling effect of ammonia. The reducing effect seemed to dominate in the low range of concentration while the size-controlling effect via the formation of AgNH32+ complex ion was important in the higher range. The TEM figures evidently confirmed the effects.

An in-depth analysis of nucleation and growth mechanism of CdS thin film synthesized by chemical bath deposition (CBD) technique

“…Generally, it was noted that the silver ions favoured a linear structural geometry because of the lack of a stereochemical www.nature.com/scientificreports/ directionality which is formed from the d 10 configuration and a relatively weak nature of the silver(I)-ligand bonds 74 . Hence, the most stable geometrical structure was seen to have a linear geometry 75 as the ground and the excited state energies for this geometrical structure were very stable 76 . In this case, one Ag ion was donated to the Cd 2+ ions.…”

Mechanism and principle of doping: realizing of silver incorporation in CdS thin filmviadoping concentration effect

“…51 Linear geometry with stable excited state energies was the most stable geometrical structure. 52,53 In this case, Ag + donated an electron to Cd 2+ . As a result of the charge transition from Ag + ions to Cd complexes, the [Cd(NH 3 ) 4 ] 2+ complexes (with a square planar geometry) were transformed into the [Cd(NH 3 ) 4 ] + complex (with a tetrahedral), resulting in the formation of unstable [Ag(NH 3 ) 2 ] 2+ linear complexes.…”

Role of the Deep Eutectic Solvent Reline in the Synthesis of Gold Nanoparticles

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“…The reducing potential of ammonia is associated with the lone pair of electrons on the nitrogen atom available for donation, and it has been widely used as a reducing agent to synthesize ZnO, CoFe 2 O 4 , and silver nanoparticles . In this latter case, ammonia forms Ag­[NH 3 ] 2 + complexes that deplete the availability of ionic silver in the medium, resulting in quasi-monodisperse silver nanoparticles. , …”