X-ray Absorption Spectroscopic Study on Interfacial Electronic Properties of FeOOH/Reduced Graphene Oxide for Asymmetric Supercapacitors

2017 ◽  
Vol 5 (4) ◽  
pp. 3186-3194 ◽  
Author(s):  
Han-Wei Chang ◽  
Chung-Li Dong ◽  
Ying-Rui Lu ◽  
Yu-Cheng Huang ◽  
Jeng-Lung Chen ◽  
...  
2016 ◽  
Vol 120 (39) ◽  
pp. 22134-22141 ◽  
Author(s):  
Han-Wei Chang ◽  
Ying-Rui Lu ◽  
Jeng-Lung Chen ◽  
Chi-Liang Chen ◽  
Jin-Ming Chen ◽  
...  

Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 990
Author(s):  
Hangil Lee ◽  
Hyun Sung Kim

While reduced graphene oxide (rGO) is used widely as a catalyst, its catalytic activity can be improved significantly by modifying it with a metal. In this study, we compared the photocatalytic and catalytic properties of base-treated rGO particles and transition-metal-ion-doped rGO based on the oxidation reaction of thiophenol and the photocatalytic degradation of 4-chlorophenol. Since the two catalytic activities are related to the changes in the electronic structure of rGO, X-ray photoemission spectroscopy, X-ray absorption spectroscopy, and Raman spectroscopy were performed. When rGO was doped with Mn2+ ions, its catalytic properties improved with respect to both reactions. The changes in the electronic structure of rGO are attributed to the formation of defect structures on the rGO surface via a reaction between the doped Mn2+ ions and oxygen of the rGO surface. Thus, the results show that the doping of rGO with Mn ions in the +2-charge state (stable oxide form: MnO) enhances its catalytic and photocatalytic activities. Hence, this study provides new insights into the use of defect-controlled rGO as a novel catalyst.


2017 ◽  
Vol 5 (24) ◽  
pp. 12578-12578
Author(s):  
Mohammad Qorbani ◽  
Tsu-chin Chou ◽  
Yi-Hsin Lee ◽  
Satyanarayana Samireddi ◽  
Naimeh Naseri ◽  
...  

Correction for ‘Multi-porous Co3O4 nanoflakes@sponge-like few-layer partially reduced graphene oxide hybrids: towards highly stable asymmetric supercapacitors’ by Mohammad Qorbani et al., J. Mater. Chem. A, 2017, DOI: 10.1039/c7ta00694b.


2021 ◽  
Author(s):  
Ashwini Patil

Abstract The present research deals with the development of a novel bioinspired in situ fabrication of reduced graphene oxide (rGO)-silver nanoparticle (AgNPs) nanocomposite (rGO@AgNCs) using microbes namely Pseudomonas aeruginosa (PA) and Staphylococcus aureus (SA). The fabricated rGO@AgNCs were characterized using Ultraviolet-visible (UV) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), particle size analysis, polydispersity index (PDI), zeta potential analysis, energy dispersive X-ray analysis (EDAX), Raman spectroscopy, powder X-ray diffraction (PXRD), high-resolution transmission electron microscopy (HR-TEM) analysis, etc. Furthermore, the rGO@AgNCs-PA and rGO@AgNCs-SA interaction with serum protein, pH stability study, and in vitro dissolution of AgNPs were also performed. The research findings of the proposed study demonstrated the simultaneous reduction of graphene oxide (GO) and AgNPs and the formation of rGO@AgNCs in the presence of microbes. The in vitro dissolution studies of rGO@AgNCs composites showed better AgNPs dissolution with controlled release and offered remarkable matrix integrity throughout the dissolution period. The size and stability of rGO@AgNCs-PA and rGO@AgNCs-SA had no significant changes at physiological pH 7.4. A minimal decrease in the zeta potential of rGO@AgNCs was observed, which may be due to the weak interaction of nanocomposites and albumin. The antibacterial application of the synthesized nanocomposite was evaluated against a pathogenic mastitis-forming bacterium. The obtained results suggested an admirable antibacterial activity of synthesized nanocomposites against the tested microbes. This knowledge will assist the scientific fraternity in designing novel antibacterial agents with enhanced antibacterial activity against various veterinary pathogens in near future.


RSC Advances ◽  
2015 ◽  
Vol 5 (21) ◽  
pp. 16319-16327 ◽  
Author(s):  
Ganesh Kumar Veerasubramani ◽  
Karthikeyan Krishnamoorthy ◽  
Sang Jae Kim

In this article, we report the fabrication and electrochemical performance of asymmetric supercapacitors (ASCs) based on a reduced graphene oxide (rGO) negative electrode and a cobalt molybdate (CoMoO4) positive electrode.


2020 ◽  
Vol 20 (7) ◽  
pp. 4035-4046
Author(s):  
Rengasamy Dhanabal ◽  
Dhanasekaran Naveena ◽  
Sivan Velmathi ◽  
Arumugam Chandra Bose

Using a simple solution based synthesis route, hexagonal MoO3 (h-MoO3) nanorods on reduced graphene oxide (RGO) sheets were prepared. The structure and morphology of resulting RGO-MoO3 nanocomposite were characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The optical property was studied using UV-Visible diffuse reflectance spectroscopy (UV-Vis DRS) and photoluminescence spectroscopy (PL). The RGO-MoO3 nanocomposites were used as an electrode for supercapacitor application and photocatalyst for photodegradation of methylene blue (MB) and rhodamine B (RhB) under visible light irradiation. We demonstrated that the RGO-MoO3 electrode is capable of delivering high specific capacitance of 134 F/g at current density of 1 A/g with outstanding cyclic stability for 2000 cycles. The RGOMoO3 photocatalyst degrades 95% of MB dye within 90 min, and a considerable recyclability up to 4 cycles was observed. The quenching effect of scavengers test confirms holes are main reactive species in the photocatalytic degradation of MB. Further, the charge transfer process between RGO and MoO3 was schematically demonstrated.


Sign in / Sign up

Export Citation Format

Share Document