Repeated Use of Cyperus esculentus Tubers, Towards Sustainable Green Synthesis of Silver Nanoparticles

Abstract

For green synthesis to be a sustainable approach for preparing nanoparticles, efforts must go into the search of methods that can guarantee effective and efficient use of bio resources. Most conventional approaches require fresh bio-reducing and stabilizing agents for every synthesis cycle. This study demonstrates that Cyperus esculentus tubers can serve as efficient bio-reducing and stabilizing agents� source for multiple syntheses of silver nanoparticles. The simple approach for extracting reducing agent from Cyperus esculentus tubers reported in this study offers the possibility to reuse the tubers for multiple syntheses. Reductants from Cyperus esculentus were obtained by soaking the tubers in deionized water for 24�hours, without the need of crushing. Addition of silver ions to the extract resulted in a rapid formation of silver nanoparticles. Effects of sunlight exposure, temperature, and pH on the formation of silver nanoparticles were studied. Silver nanoparticles were obtained in seconds under sunlight exposure, minutes at basic conditions, and hours under room and elevated temperatures. In addition, the Cyperus esculentus tubers could be used multiple times for the preparation of silver nanoparticles, thus serving as a sustainable bio reducing and stabilizing agents� source for the preparation of silver nanoparticles. The results from this study offers a simple, convenient, and economical approach for sustainable green synthesis of silver nanoparticles. � 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.