Highly stable AgNPs prepared via a novel green approach for catalytic and photocatalytic removal of biological and non-biological pollutants. (October 2020)

• Record Type: Journal Article
• Authors: Rani, Pooja; Kumar, Vanish; Singh, Prit Pal; Matharu, Avtar Singh; Zhang, Wei; Kim, Ki-Hyun; Singh, Jagpreet; Rawat, Mohit
• Is Part Of: Environment international. Volume 143(2020)
• Publication Date: 2020-10
• Subjects: Phaseolus Vulgaris -- Silver nanoparticles -- Green synthesis -- 4-nitrophenol -- Catalytic activity -- Photocatalytic degradation; Environmental protection -- Periodicals; Environmental health -- Periodicals; Environmental monitoring -- Periodicals; Environmental Monitoring -- Periodicals; Environnement -- Protection -- Périodiques; Hygiène du milieu -- Périodiques; Environnement -- Surveillance -- Périodiques; Environmental health; Environmental monitoring; Environmental protection; Periodicals; 333.705
• DOI: 10.1016/j.envint.2020.105924
• Languages: English
• ISSNs: 0160-4120

Abstract

Graphical abstract: Highlights: Environmentally friendly synthesis of AgNPs is realized using kidney bean seed extract. AgNPs have a spherical morphology with a face-centered cubic crystal structure. The synthesized AgNPs showed long-term stability due to capping of biomolecules. AgNPs showed excellent photocatalytic/catalytic and antimicrobial potential. Abstract: Increases in biological and non-biological pollutants pose a significant threat to environmental systems. In an effort to develop an effective means to treat such pollutants, the use of Phaseolus vulgaris (kidney beans) as reducing and capping agents is proposed for the green synthesis of highly stable silver nanoparticles (AgNPs) with a face-centered cubic ( fcc) crystalline structure (size range: 10–20 nm). The potent role of the resulting AgNPs was found as triple platforms (photocatalyst, catalyst, and antimicrobial disinfectant). AgNPs were able to photocatalytically degrade approximately 97% of reactive red-141 (RR-141) dye within 150 min of exposure (quantum efficiency of 3.68 × 10 -6 molecule.photon -1 and a removal reaction kinetic rate of 1.13 × 10 -2 mmol g −1 h −1 ). The role of specific reactive oxygen species (ROS) in the photocatalytic process and complete mineralization of dye was also explored through scavenger and chemical oxygen demand (COD) experiments, respectively. As an catalyst, AgNPs were also capable of reducing 4-nitrophenol to 4-aminophenol within 15 min. Overall, AgNPs showed excellent stability as catalyst and photocatalyst even after five test cycles. As an antimicrobial agent, the AgNPs are effective against both gram-positive ( Bacillus subtilis ) and -negative bacteria ( Escherichia coli), with the zones of clearance as 15 and 18 mm, respectively. Thus, the results of this study validate the triple role of AgNPs derived via green synthesis as a photocatalyst, catalyst, and antimicrobial agent for effective environmental remediation.