Green route synthesis of silver nanoparticles using plants/ginger extracts with enhanced surface plasmon resonance and degradation of textile dye

Silver nanoparticles (AgNPs) of 10-20 nm sized were synthesized via eco-friendly and cost-effective green methods using ginger (Zingiber officinale) extract and exhibit an excellent crystalline structure. The AgNPs show absorption maximum at around 407 nm at an optimal pH of 10, hence exhibits a strong surface plasmon resonance (SPR), which arises when the interaction of free electron oscillation of AgNPs is in resonance with the frequency of light interacted. AgNPs growth could be controlled by changing environmental factors such as pH, temperature, reaction time and concentration. The development of AgNPs using ginger extract is much higher as compared to tulsi (Ocimum sanctum) and neem (Azadirachta indica), plant nectar (honey), pomegranate peel extracts and fructose. In the presence of catalyst AgNPs, the absolute absorption intensity (absorbance) of textile dye, methylene blue (MB) is reduced dramatically by sodium borohydride (NaBH4). The absorbance of MB diminished 99.9% and the solution became colorless (in 10 min). Thus, the hazardous dye is degraded faster by AgNPs than the metal oxides/NPs used so far. Note that most medicinal plant extracts used in the present study are quite helpful for several diseases, including coronavirus (Covid-19).