Papers by Anil Suryawanshi
The Analyst, Jan 2, 2015
Photoluminescent carbon dots of 4-5 nm size were prepared from starch (Tapioca Sago) through a so... more Photoluminescent carbon dots of 4-5 nm size were prepared from starch (Tapioca Sago) through a solution method under mild conditions. The as-prepared carbon dots were used as photoluminescence probes for highly anion selective fluoride ion detection in aqueous solutions. A ready-to-use device is also demonstrated.
Nanoscale, 2014
Graphene quantum dots (GQDs) are synthesized from bio-waste and are further modified to produce a... more Graphene quantum dots (GQDs) are synthesized from bio-waste and are further modified to produce amine-terminated GQDs (Am-GQDs) which have higher dispersibility and photoluminescence intensity than those of GQDs. A strong fluorescence quenching of Am-GQDs (switch-off) is observed for a number of metal ions, but only for the Ag(+) ions is the original fluorescence regenerated (switch-on) upon addition of L-cysteine.
Catalysis Science & Technology, 2014
A composite of reduced graphene oxide (RGO) with oxides of manganese and cobalt together was prep... more A composite of reduced graphene oxide (RGO) with oxides of manganese and cobalt together was prepared by a solvothermal method. During synthesis, both the reduction of graphene oxide as well as the growth of nanorod shaped CoMn 2 O 4 and Co 3 O 4 occurred simultaneously having a crystallite size of~8 nm calculated from X-ray diffraction (XRD). The as-obtained triple nanocomposite material designated as RGO-MnCoO exhibited excellent activity for the liquid phase aerobic oxidation of aromatic alcohols under base-free conditions selectively giving the corresponding aldehydes (>85%). RGO loading was varied in the range of 1-10%, among which 1% RGO-MnCoO showed maximum catalytic activity enhancement of 24% as compared to the bare mixed oxide (MnCo-MO) for the oxidation of vanillyl alcohol. HR-TEM of RGO-MnCoO revealed that it was a composite material having uniform nanotubes of~25 nm length and 6 nm diameter with a fringe pattern showing the and planes and lattice spaces of 0.26 nm and 0.22 nm, respectively, for the spinel CoMn 2 O 4 . The detailed studies on the morphology, size and composition of the as-prepared RGO-MnCoO nanocomposite by XRD, XPS, N 2 -adsorption/desorption and O 2 -TPD techniques were used to understand the role of RGO in the enhancement of catalytic activity for oxidation reaction.
Electrochimica Acta, 2014
Keywords: Na-ion battery anode disordered carbon indanthrone A B S T R A C T We report facile, on... more Keywords: Na-ion battery anode disordered carbon indanthrone A B S T R A C T We report facile, one step synthesis of disordered graphitic carbon by high temperature (1000 C) pyrolysis of indanthrone dye (ID). The pyrolysed carbon is disordered in nature and the same is clearly evidenced by various analytical techniques like X-ray diffraction, Raman spectroscopy and high resolution transmission electron microscopy. Na-insertion properties of such indanthrone dye derived disordered graphitic carbon (IDDGC) is evaluated in half-cell assembly (Na/IDDGC). The test cell delivered a reversible capacity of $160 mAh g À1 at current density of 25 mA g À1 . In addition, excellent cycling profiles are noted for such IDDGC, which retains $67% of initial reversible capacity after 500 cycles. The present study clearly highlights the importance of disorder in the graphitic carbon for efficient Na-ion storage.
Small, 2013
High performance is reported for a symmetric ultracapacitor (UC) cell made up of hierarchically p... more High performance is reported for a symmetric ultracapacitor (UC) cell made up of hierarchically perforated graphene nanosheets (HPGN) as an electrode material with excellent values of energy density (68.43 Wh kg⁻¹) and power density (36.31 kW kg⁻¹). Perforations are incorporated in the graphite oxide (GO) and graphene system at room temperature by using silica nanoparticles as template. The symmetric HPGN-based UC cell exhibits excellent specific capacitance (Cs) of 492 F g⁻¹ at 0.1 A g⁻¹ and 200 F g⁻¹ at 20 A g⁻¹ in 1 M H₂SO₄ electrolyte. This performance is further highlighted by galvanostatic charge-discharge study at 2 A g⁻¹ over a large number (1000) of cycles exhibiting 93% retention of the initial Cs. These property features are far superior as compared to those of symmetric UC cells made up of only graphene nanosheets (GNs), i.e. graphene sheets without perforations. The latter exhibit Cs of only 158 F g⁻¹ at 0.1 A g⁻¹ and the cells is not stable at high current density.
Journal of Materials Chemistry, 2012
ABSTRACT A triethylene glycol (trigol) based simple approach is reported for the reduction of gra... more ABSTRACT A triethylene glycol (trigol) based simple approach is reported for the reduction of graphite oxide (GO). This protocol produces high quality graphene which we term as trigol reduced graphene (TRG) and its relevant properties including electrical conductivity and energy storage capacity are comparable to those of graphene obtained by the conventional hydrazine based approach. The achieved specific capacitance for TRG is 130 F g−1 with an energy density value of 18 W h kg−1. This work opens up a new promising synthetic route for the development of graphene and graphene based nanocomposites for various energy related applications.
International Journal of Hydrogen Energy, 2012
Visible-light water splitting a b s t r a c t Nanocomposite of graphitic carbon nitride (g-C 3 N ... more Visible-light water splitting a b s t r a c t Nanocomposite of graphitic carbon nitride (g-C 3 N 4 ) with optimum concentration of multiwall carbon nanotubes (MWCNTs) is shown to render 100% improvement in its photocatalytic activity for visible-light induced water splitting. Our study reveals that in addition to the charge transfer effects, morphological changes in g-C 3 N 4 introduced by mild MWCNT reinforcement play a vital role in the photocatalytic activity. We present results of structural and opto-electronic characterizations in support of these inferences.
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Papers by Anil Suryawanshi