Microbial synthesis of graphene‐supported highly‐dispersed Pd‐Ag bimetallic nanoparticles and its catalytic activity

Abstract

BACKGROUND Graphene‐supported nanocomposites are promising catalysts for their unique properties. Biosynthesis of such hybrid catalysts possesses several advantages over other methods such as less pollution. The palladium nanoparticle has versatile catalytic activities and its stability and activities can be significantly improved through hybridization with other nanomaterials including graphene. RESULTS In this study, bimetallic palladium‐silver nanoparticles supported on graphene (Pd‐Ag/rGO) was prepared through one‐step biosynthesis using a bacterium Shewanella oneidensis MR‐1. Shewanella oneidensis MR‐1 synthesized Pd‐Ag/rGO through simultaneous reduction of silver nitrate (AgNO3), palladium(II) nitrate (Pd(NO3)2) and graphene oxide (GO). The morphology and composition of the Pd‐Ag/rGO were characterized by transmission electron microscopy, energy dispersive X‐ray, X‐ray diffraction, X‐ray photoelectron spectroscopy, Fourier‐transform infrared spectroscopy and Raman spectroscopy. Furthermore, the hydrogenation activity of synthesized Pd‐Ag/rGO was tested using 4‐nitrophenol as a model chemical at room temperatures and pressure. The Pd‐Ag/rGO showed the best catalytic performance when Pd/Ag ratio was 1:1 and bacterial concentration was 1.0 of OD600 (optical density measured at a wavelength of 600 nm) for the preparation of Pd‐Ag/rGO. Therefore, the kinetic rate constant for 4‐NP reduction was 0.2413 min−1 catalyzed by as‐prepared Pd‐Ag/rGO, which is listed as one of the top level reported catalysts for 4‐NP reduction. CONCLUSION Therefore, this study demonstrated a material and energy‐saving method to synthesize hybrid nanoparticles supported on graphene with high catalytic activity. © 2019 Society of Chemical Industry

Synthesis, Properties, and Biological Applications of Metallic Alloy Nanoparticles

“…The genes, proteins, enzymes, and biomolecules of the microorganisms play roles as reducing factors. Bacteria such as Escherichia coli , Salmonella typhimurium, Listeria monocytogenes , Bacillus subtilis, and Rhodopseudomonas capsulata [ 150 , 151 , 152 , 153 , 154 , 155 , 156 , 157 ] have been used to create Au–Pd, Pd–Pt, Pd–Ag, Au–Ag, Pd–Fe, Au–Fe, Pd–Au–Fe, and Cu–Ag alloy nanoparticles.…”

Microbiologically-Synthesized Nanoparticles and Their Role in Silencing the Biofilm Signaling Cascade

“…where SO 4 2− is first reduced to S 2− by the sulfate-reducing bacteria, and then S 2− gradually combined with Pb +2 to precipitate as PbS-NPs (Qi et al, 2016;Yue et al, 2016). Studies have also shown that grapheme-associated highly dispersed Pd-Ag bimetallic NPs can be synthesized using Shewanella oneidensis MR-1 (Han et al, 2019). The conversion of graphene oxides to grapheme nano sheets can be achieved through the use of crude polysaccharides obtained from Pleurotus flabellatus (Dasgupta et al, 2017; Figure 1).…”

Bacterial extracellular electron transfer: a powerful route to the green biosynthesis of inorganic nanomaterials for multifunctional applications

“…Dong et al developed an Au-NPs/RGO nanohybrid synthesized by using S. oneidensis MR-1 without the addition of any toxic agents, which showed comparable structural features and a better catalytic activity towards the reductive removal of nitroaromatics [ 182 ]. The similar approaches have also been adopted to biosynthesize Ag-NPs/RGO [ 164 ], Pd-NPs/RGO [ 183 ], Pd-Au/RGO[ 25 ] and Pd–Ag/rGO[ 168 ] nanocomposites.…”

“…Carbon nanomaterials having high surface area, conductivity and stability are very promising to address this concern. Various biogenic MNPs including Ag-NPs [ 193 ], Cu-NPs[ 105 ] and Pd/Ag alloys[ 168 ] have been integrated into either carbon nanotubes or graphene as efficient catalysts for organic contaminant removal. Additionally, the conversion of bacterial cell biomass to porous carbon matrix through KOH activation at a high temperature was also developed to improve the catalytic activity of biogenic Pd-NPs [ 22 ].…”