Shewanella oneidensis Assisted Biosynthesis of Pd/Reductive‐Graphene‐Oxide Nanocomposites for Oxygen Reduction Reaction

Abstract

Biological synthesis of green nanomaterials holds great promise for sustainable catalysis with versatile applications. Herein, Shewanella oneidensis MR‐1 is used to develop a green method to synthesize Pd/reductive graphene oxide (rGO) nanocomposites without the addition of toxic reducing agents. It was found that S. oneidensis MR‐1 cells could efficiently reduce graphene oxide to rGO and synthesize Pd nanoparticles that uniformly dispersed on the rGO nanosheets. More strikingly, the addition of GO greatly increases the recovery rate of Pd from 37.8 % to 90.4 %. After carbonization, the biosynthesized Pd/rGO nanocomposites exhibits promising catalytic activities toward oxygen reduction reaction with an onset potential of 0.92 V, a half‐wave potential of 0.81 V, and a limiting current density of 5.2 mA cm−2 in 0.1 M KOH electrolyte. This work provides a simple, “green”, and cost‐effective method for the preparation of graphene supported nanocomposites with extended applications.

Biotechnological synthesis of Pd-based nanoparticle catalysts

“…226,227 Bio-Pd commonly undergoes modication via pyrolysis and/or the incorporation of rGO for use in fuel cells. [228][229][230][231] Recent studies have incorporated various nanomaterials with bacteria, such as metal-organic frameworks (MOFs) and TiO 2 nanotubes, which enhanced the adsorption and reduction of various environmental contaminants. [232][233][234] Another study integrated the synthesis of a photoactive polymer onto microbial surfaces through bio-Pd catalysed Sonogashira polymerisation.…”

“…226,227 Bio-Pd commonly undergoes modification via pyrolysis and/or the incorporation of rGO for use in fuel cells. 228–231…”

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.…”

“…After simple KOH activation at 420 °C, S. oneidensis MR-1 cells were converted into highly porous heteroatom-doped carbon supporting uniform Pd-NPs, and consequently, the as-prepared hybrid nanomaterials showed 2.2-fold higher specific mass catalytic activity, better durability and methanol tolerance compared to the commercial Pt/C catalyst. Recently, Wang et al synthesized a Pd/RGO hybrid catalyst through using S. oneidensis MR-1 as the biological reducing agent, which showed promising electrocatalytic activity towards oxygen reduction reaction in alkaline electrolyte [ 183 ]. Jiang and co-workers fabricated another efficient oxygen reduction catalyst of Mn 2 O 3 micro-/nanocubes through calcination of biogenic MnCO 3 precursors that were produced by S. loihica PV-4 in the presence of MnO 4 − as the sole acceptor [ 192 ].…”

Comparative Study of CuO, Fe3O4 and CuFe2O4/CuO over Montmorillonite Clay: Green Synthesis, Characterization and Catalytic Activity

“…[12] There are many reports on the synthesis of nanoparticles in the presence of various plant extracts. [13] T. chebula (Figure 1), commonly known as chebulic-or black Myrobalan belonging to the family Combretaceae, is a significantly important medicinal plant that it has the following properties: anticancer, antidiabetic, antifungal, antiviral, and antibacterial agents. [14] Some phytochemicals present in this plant are flavonoids, tannins, terpenoids, and gallic acid (Figure 1).…”