“…1 h). Studies have reported thinner GO sheets (Huang et al 2011; He et al 2015a; Mukherjee et al 2016; Rathnayake et al 2017; Chu et al 2018); however, this is possibly due to prolonged graphite exfoliation which reduces the thickness of GO sheets.Fig. 1Lateral size in micrometres and height (thickness) in nanometres of GO sheets using TEM and AFM, respectively.…”
Graphene oxide (GO) has been reported to possess antibacterial activity; therefore, its accumulation in the environment could affect microbial communities such as biofilms. The susceptibility of biofilms to antimicrobials is known to depend on the stage of biofilm maturity. The aim of this study was to investigate the effect of GO nano-particles on
Pseudomonas putida
KT2440 biofilm of variable age. FT-IR, UV-vis, and Raman spectroscopy confirmed the oxidation of graphene while XPS confirmed the high purity of the synthesised GO over 6 months. Biofilms varying in maturity (24, 48, and 72 h) were formed using a CDC reactor and were treated with GO (85 μg/mL or 8.5 μg/mL). The viability of
P. putida
was monitored by culture on media and the bacterial membrane integrity was assessed using flow cytometry.
P. putida
cells were observed using confocal microscopy and SEM. The results showed that GO significantly reduced the viability of 48-h biofilm and detached biofilm cells associated with membrane damage while the viability was not affected in 24- and 72-h biofilms and detached biofilm cells. The results showed that susceptibility of
P. putida
biofilm to GO varied according to age which may be due to changes in the physiological state of cells during maturation.
Graphical abstract
Electronic supplementary material
The online version of this article (10.1007/s11356-019-05688-9) contains supplementary material, which is available to authorized users.
“…1 h). Studies have reported thinner GO sheets (Huang et al 2011; He et al 2015a; Mukherjee et al 2016; Rathnayake et al 2017; Chu et al 2018); however, this is possibly due to prolonged graphite exfoliation which reduces the thickness of GO sheets.Fig. 1Lateral size in micrometres and height (thickness) in nanometres of GO sheets using TEM and AFM, respectively.…”
Graphene oxide (GO) has been reported to possess antibacterial activity; therefore, its accumulation in the environment could affect microbial communities such as biofilms. The susceptibility of biofilms to antimicrobials is known to depend on the stage of biofilm maturity. The aim of this study was to investigate the effect of GO nano-particles on
Pseudomonas putida
KT2440 biofilm of variable age. FT-IR, UV-vis, and Raman spectroscopy confirmed the oxidation of graphene while XPS confirmed the high purity of the synthesised GO over 6 months. Biofilms varying in maturity (24, 48, and 72 h) were formed using a CDC reactor and were treated with GO (85 μg/mL or 8.5 μg/mL). The viability of
P. putida
was monitored by culture on media and the bacterial membrane integrity was assessed using flow cytometry.
P. putida
cells were observed using confocal microscopy and SEM. The results showed that GO significantly reduced the viability of 48-h biofilm and detached biofilm cells associated with membrane damage while the viability was not affected in 24- and 72-h biofilms and detached biofilm cells. The results showed that susceptibility of
P. putida
biofilm to GO varied according to age which may be due to changes in the physiological state of cells during maturation.
Graphical abstract
Electronic supplementary material
The online version of this article (10.1007/s11356-019-05688-9) contains supplementary material, which is available to authorized users.
“…The HRTEM image (Fig. 7 b) of Pd@GO shows an amorphous characteristic of graphene sheets 24 . The Pd@GO/MOF image in Fig.…”
Section: Resultsmentioning
confidence: 98%
“…Moreover, it has been reported that modification of MOF surface with a carbon-based material such as graphene oxide (GO) improves the structural properties of MOF 23 – 27 due to GO’s rich functional oxygen groups and conjugate network of graphitic structure. These structural properties of GO enhance the electrical conductivity and the dispersive forces when incorporating it into other materials to form composites 23 , 24 . For example, a composite of cobalt oxide (Co 3 O 4 )-decorated reduced graphene oxide (rGO)-based nanoelectrodes showed to have good electrochemical performance for water splitting reactions in an alkaline medium 3 .…”
In this study, a nanocomposite of palladium supported graphene oxide (GO)/metal–organic framework (MOF) was prepared using electroless deposition of Pd on GO followed by impregnation method of Pd@GO and MOF. The prepared materials were characterized with various analytical techniques and their applications as HER electrocatalysts were evaluated using cyclic voltammetry (CV), Tafel plots, and turn over frequencies (TOFs). The HER results showed a radical increment of H2 production in the nanocomposite through the Volmer reaction together with Heyrovsky or Tafel mechanism. This disclosed that the addition of Pd@GO/MOF in the electrolytic system possessed better catalytic characteristics with enhanced current density which may open a new way for hydrogen production and storage via HER.
“…These materials are commonly available and even showcase similar properties to that of graphene. There are several ways to produce single or few-layer graphene (Figure 10), such as mechanical cleavage, 58 epitaxial growth in high vacuum chamber, 58,59 graphitization of SiC in atmospheric pressure, oxidation of graphite to produce graphite oxide, 64,65 chemical vapour deposition (CVD) using catalyst transition metal 66,67 and liquid phase exfoliation techniques. 68 Among those methods, low cost and high-quality materials are only obtained from direct liquid phase exfoliation technique.…”
Section: Graphene: Preparation Processing and Dispersion Techniquesmentioning
This articles reviews till-date available literature on metal matrix composites reinforced with graphene, CNT and other carbonaceous materials. The article has a special focus on the mechanical, tribological and challenges associated with the fabrication of nanocomposites. Simultaneously, it reviews the synthesis, strengthening mechanism and applications of graphene along with research gap associated with graphene metal matrix nanocomposites (GMMNC). Carbonaceous nanofillers, e.g. Graphene, are known to have extraordinary mechanical, thermal and electrical properties along with multifaceted characteristics. These materials have the potential to become an ideal material in numerous application which requires reinforcement. Graphene nanoplatelets (GNP) suffers various challenges starting from its synthesis to the uniform distribution within the matrix material. Our concern is to give details on the challenges associated with graphene and metal matrix composites along with the solution so that new research can be done at its ease. Section 1 of the article gives a detailed analysis of various carbonaceous reinforcement materials. Preparation, processing and dispersion technique for graphene and composite material is given in section 2. Section 3 of the article deals with different matrix material used in MMNC along with the properties and challenges associated with it in tabulated form. Strengthening mechanism used for the enhancement of mechanical properties of composites is described in section 4, whereas, Section 5 deals with the applications and Research gap.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
