Microbial reduction of graphene oxide by Azotobacter chroococcum

Abstract

We report an eco-friendly route for the reduction of graphene oxide (GO) by Azotobacter chroococcum at room temperature. Examinations using X-ray photoelectron spectroscopy, X-ray diffraction, and transmission electron microscopy indicate the formation of reduced graphene oxide (rGO) with a low degree of agglomeration. Quantitative analyses of electron diffraction data show that the produced rGO consists of single-layer sheets with a random stacking. It is suggested that the GO was reduced directly by the nitrogenase via sequential additions of electrons and protons followed by dehydration. This approach avoids the use of toxic chemical agents and also reduces the agglomeration of rGO.

Protective Effects of Radix Sophorae Flavescentis Carbonisata-Based Carbon Dots Against Ethanol‐Induced Acute Gastric Ulcer in Rats: Anti-Inflammatory and Antioxidant Activities

“…The high-resolution spectrum of C 1s ( Figure 3B ) could be deconvoluted into three peaks at 284.1 (C-C/C=C), 285.6 (C-O/C=N) and 287.6 eV (C=O). 35 , 36 In the high-resolution O 1s spectrum ( Figure 3C ), two peaks at 530.5 and 531.9 eV were attributed to the presence of O-H and O-C=O bonds, respectively. 37 , 38 Two peaks at 399.3 and 400.3 eV were in the high-resolution N 1s spectrum ( Figure 3D ), revealing the existence of pyridinic N and pyrrolic N. 39 The synthesis yield of RSFC-CDs was 3.14 ± 0.2%.…”

The inhibitory impacts of nano-graphene oxide on methane production from waste activated sludge in anaerobic digestion

“…were then breakdown by anaerobic bacteria and eventually converted to methane by methanogens (Sun et al, 2014;Sun et al, 2015;Tian et al, 2017). Previous investigations have reported that nano-graphene and Fe 3 O 4 nanoparticles induced positive effects on the methane yield (Li et al, 2015;Tian et al, 2017).…”

“…For example, thermal treatment of the NGO-WAS mixture could be applied to remove carboxyl groups of NGO to release the absorbed SCOD from NGO (McAllister et al, 2007;Schniepp et al, 2006;Zhu et al, 2017), which would potentially facilitate the carbon transformation and methane production from WAS. Also, chemical reduction of hydrazine vapor could also be tried transfer NGO to the form of graphene (Gao et al, 2010;Park et al, 2012;Ren et al, 2011), which has been demonstrated to be able to facilitate methane production in anaerobic digestion (Tian et al, 2017). In addition, microbial reduction could serve as an environmental-friendly method to replace chemical and thermal reduction of NGO.…”

“…reduce NGO to the form of graphene to avoid the inhibitory effect of NGO (Chen et al, 2017;Gurunathan et al, 2013;Wang et al, 2011b). Given that the anaerobic digestion communities had a high biodiversity, further investigation are worthy to be carried out to explore their potential on NGO reduction.…”

Plasma Assisted Reduction of Graphene Oxide Films

“…However, the C/O atomic ratio and electrical conductivity obtained are inferior to the chemical methods [ 42 , 52 ]. Microbes such as Shewanella [ 132 ] , E. coli [ 133 ] , yeast [ 134 ] , and Azotobacter chroococcum [ 135 ] can also reduce GO in the forms of dispersion or film. Though such biological agents are attractive with low-negative environmental impact, they are limited in terms of the need for sensitive culture procedure and prolonged reaction time [ 49 ].…”