Catalytic reduction of anionic and cationic toxic dyes and evaluation of antimicrobial activity using green synthesized palladium nanoparticles employing Carica papaya aqueous leaf extract

Abstract

The present study offers a flexible method for the ecologically friendly synthesis of palladium nanoparticles and their assessment as a catalyst and antibacterial agent. Using an aqueous leaf extract of Carica papaya as a capping and reducing agent with Total Organic Carbon (TOC) measured at 959 mg/L, palladium nanoparticles (PdNPs) were biochemically created. This is undoubtedly a modest green synthesis method, and the structural characteristics of the nanoparticles were investigated utilizing the techniques of UV, FTIR, powder XRD, SEM, and HR-TEM. According to FTIR studies, the polyphenols in Carica papaya leaf extract may be what causes Pd2+ to be converted into PdNPs. The face-centered cubic geometry of the PdNPs was extremely crystalline, as shown by the X-ray diffraction., and SEM images confirmed their spherical shape. The particle size of the synthesized PdNPs was found to be 20 nm as determined by HR-TEM. In the reduction of anionic Congo red (CR) and cationic Methylene blue (MB) dyes, green-produced PdNPs showed substantial catalytic activity. The PdNPs may have a catalytic impact as seen by the decrease in absorption band intensity with passing time, which results in 92 % degradation of Congo red, an anionic dye, and 95 % degradation of Methylene Blue, a cationic dye. Significant antibacterial action was also shown by the synthetic green PdNPs against bacterial and fungi strains.

Keywords

• Palladium nanoparticles (PdNPs)
• Carica papaya leaf extract
• Methylene blue (MB)
• Congo red (CR)
• Antimicrobial activity