Bactericidal and catalytic performance of green nanocomposite based-on chitosan/carbon black fiber supported monometallic and bimetallic nanoparticles.

Nanoparticles were synthesized on the surface of green nanocomposite based on carbon black dispersed in chitosan (CB-CS) fibres. The nanoparticles were monometallic Co, Ag and Cu and bimetallic Co + Cu and Co + Ag. The CB-CS fibres were prepared and introduced into separate metal salt solutions containing Co2+, Ag+ and Cu2+ and mixed Co2++Cu2+ and Co2++Ag+ ions. The metal ions immobilized on the surface of CB-CS were reduced using sodium borohydride (NaBH4) as reducing agent to synthesize the corresponding zero-valent metal nanoparticles-loaded CB-CS fibres. All the nanoparticles-loaded CB-CS samples were characterized using field emission-scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction techniques. When tested as catalysts, the nanoparticles-loaded CB-CS showed excellent catalytic ability for the reduction of toxic and environmentally unwanted pollutants of para-nitrophenol, congo red and methyl orange dyes. Afterwards, the antimicrobial activities of virgin and metal-loaded CB-CS fibres were tested and the metal-loaded CB-CS fibres were found to be effective against Escherichia coli. In addition, the catalyst can be recovered easily by simply removing the fibres from the reaction mixture and can be recycled several times while maintaining high catalytic efficiency.