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High-quality graphene is highly enviable material due to its seminal role amongst several areas in modern technology including its role as nanocarrier for site selective drug grafting and delivery applications. Here, we report a facile, cost-effective and single-step method to produce high-quality graphene through customised electrochemical exfoliation of graphite anode in alkaline electrolyte medium. The quality of graphene sheets (GS) were investigated by Raman, TEM/HRTEM, AFM, and FTIR techniques. The high quality as well as excellent Π-Π stacking nature of the honeycomb lattice of graphene was confirmed by measuring the quenching capability through photo-luminescence spectroscopy using organic dyes. A plausible mechanism for the graphite exfoliation has been given where evolution of high density of oxygen molecules exerts large force on the graphitic layers leads to exfoliation and consequent synthesis of graphene. Furthermore, to explore the application of the graphene sheets so synthesized, we carried out studies which may make them as suitable carriers for drug delivery. For this, graphene sheets were functionalized with L-cysteine and attached with the drugs Amphotericin-B (AmB) and Tamoxifen citrate (TMX). The conjugation of drugs with L-cysteine functionalized graphene has been confirmed through FTIR and Raman spectroscopic techniques. The drug loading efficiency of FGS for AmB and TMX was 75.00% and 94.31%, respectively. The present formulation of drugs (AmB and TMX) conjugated with graphene is suitable for the targeted drug delivery as it will enhance the efficacy and reduce cytotoxicity associated with drug.
Assuntos
Grafite , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Eletrólitos , Análise Espectral RamanRESUMO
The present investigation describes the synergistic role of Li4(BH4)(NH2)3 and ZrFe2 in the hydrogen storage behaviour of a Li-Mg-N-H hydride system. The onset desorption temperature of ZrFe2-catalysed Mg(NH2)2-LiH-Li4(BH4)(NH2)3 is â¼122 °C, which is 83 °C, 63 °C, and 28 °C lower than that of thermally treated 2LiNH2-1MgH2, 2LiNH2-1MgH2-4 wt%ZrFe2, and 2LiNH2-1MgH2-0.1LiBH4 composites, respectively. Native Mg(NH2)2-LiH-Li4(BH4)(NH2)3 absorbed only 2.78 wt% of H2 within 30 min. On the other hand, the ZrFe2-catalysed Mg(NH2)2-LiH-Li4(BH4)(NH2)3 sample absorbed 3.70 wt% of hydrogen within 30 min and 5 wt% of H2 in 6 h at 180 °C and 7 MPa H2 pressure. Mg(NH2)2-LiH-Li4(BH4)(NH2)3 catalyzed with ZrFe2 shows negligible degradation of the storage capacity even after repeated cycles of de/rehydrogenation. The effect of ZrFe2 and Li4(BH4)(NH2)3 on a Mg(NH2)2/LiH composite has been described and discussed with the help of structural (X-ray diffraction), microstructural (electron microscopy), and vibrational modes of molecules through FTIR studies. The present results suggest that an optimum catalysis may originate from the synergistic action of an in situ formed quaternary hydride (Li4(BH4)(NH2)3) and an intermetallic-like ZrFe2, which acts as a pulverizer cum catalyst.
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The present report describes the catalytic activity of mechanically activated nano quasicrystalline Al65Cu20Fe15 and related nano crystalline Al50Cu28Fe22 for the synthesis of carbon nanotubes (CNTs). CNTs are synthesized by catalytic decomposition of ethanol through nano quasicrystalline Al65Cu20Fe15 and related crystalline Al50Cu28Fe22 alloys as a catalyst. The synthesized multi-walled CNTs exhibits tube diameter ranging from 5 to 25 nm. The synthesized CNTs are characterized by scanning and transmission electron microscopy. It is found that Al65Cu20Fe15 nanoquasicystal shows better catalytic behaviour as compared to nano-crystalline Al50Cu28Fe22 alloys for decomposition of ethanol during the synthesis of multi-walled CNTs.
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Nanopartículas , Nanotubos de Carbono , Catálise , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Difração de PóRESUMO
The present paper explores the enhancement in hydrogen sorption behavior of MgH2 with TiO2 nanoparticles. The catalytic effect of TiO2 nanoparticles with different sizes (7, 25, 50, 100 and 250 nm) were used for improving the sorption characteristics of MgH2. The MgH2 catalyzed with 50 nm of TiO2 exhibited the optimum catalytic effect for hydrogen sorption behavior. The desorption temperature of MgH2 catalyzed through 50 nm TiO2 was found to be 310 degrees C. This is 80 degrees C lower as compared to MgH2 having a desorption temperature of 390 degrees C. It was noticed that the dehydrogenated MgH2 catalyzed with 50 nm TiO2 reabsorbed 5.1 wt% of H2 within 6 minutes at temperature and pressure of 250 degrees C and 50 atm, respectively. The 50 nm TiO2 catalyst lowered the absorption activation energy of MgH2 from - 92 to - 52.7 kJ mol(-1).
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In the present study, enzyme urease has been immobilized on amine-functionalized gold nanoparticles (AuNPs). AuNPs were synthesized using natural precursor, i.e., clove extract and amine functionalized through 0.004 M L: -cysteine. Enzyme (urease) was extracted and purified from the vegetable waste, i.e., seeds of pumpkin to apparent homogeneity (sp. activity 353 U/mg protein). FTIR spectroscopy and transmission electron microscopy was used to characterize the immobilized enzyme. The immobilized enzyme exhibited enhanced activity as compared with the enzyme in the solution, especially, at lower enzyme concentration. Based on the evaluation of activity assay of the immobilized enzyme, it was found that the immobilized enzyme was quite stable for about a month and could successfully be used even after eight cycles having enzyme activity of about 47%. In addition to this central composite design (CCD) with the help of MINITAB version 15 Software was utilized to optimize the process variables viz., pH and temperature affecting the enzyme activity upon immobilization on AuNPs. The results predicted by the design were found in good agreement (R2 = 96.38%) with the experimental results indicating the applicability of proposed model. The multiple regression analysis and ANOVA showed the individual and cumulative effect of pH and temperature on enzyme activity indicating that the activity increased with the increase of pH up to 7.5 and temperature 75 °C. The effects of each variables represented by main effect plot, 3D surface plot, isoresponse contour plot and optimized plot were helpful in predicting results by performing a limited set of experiments.
Assuntos
Cucurbita/enzimologia , Enzimas Imobilizadas/metabolismo , Nanopartículas/química , Projetos de Pesquisa/estatística & dados numéricos , Urease , Análise de Variância , Interpretação Estatística de Dados , Monitoramento Ambiental/métodos , Ouro/química , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Análise de Regressão , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Urease/química , Urease/metabolismoRESUMO
The present study reports on the structural and magnetic phase transitions in Pr-doped polycrystalline Tb0.6Pr0.4MnO3, using high-resolution neutron powder diffraction (NPD) collected at SINQ spallation source, to emphasize the suppression of the sinusoidal magnetic structure of pure TbMnO3and the evolution to a collinear A-type antiferromagnetic ordering. The phase purity, Jahn-Teller distortion, and one-electron bandwidth for egorbital of Mn3+cation have been calculated for polycrystalline Tb0.6Pr0.4MnO3,in comparison to the parent materials TbMnO3and PrMnO3, through the Rietveld refinement study from x-ray diffraction data at room temperature, which reveals the GdFeO3type orthorhombic structure of Tb0.6Pr0.4MnO3havingPnmaspace group symmetry. The temperature-dependent zero field-cooled and field-cooled dc magnetization study at low temperature down to 5 K reveals a variation in the magnetic phase transition due to the effect of Pr3+substitution at the Tb3+site, which gives the signature of the antiferromagnetic nature of the sample, with a weak ferromagnetic component at low temperature-induced by an external magnetic field. The field-dependent magnetization study at low temperatures gives the weak coercivity having the order of 2 kOe, which is expected due to the canted-spin arrangement or ferromagnetic nature of Terbium ordering. The NPD data for Tb0.6Pr0.4MnO3confirms that the nuclear structure of the synthesized sample maintains its orthorhombic symmetry down to 1.5 K. Also, the magnetic structures have been solved at 50 K, 25 K, and 1.5 K through the NPD study, which shows an A-type antiferromagnetic spin arrangement having the magnetic space groupPn'ma'.
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ß-Amylase was immobilized onto GQDs using 3-aminopropyltriethoxysilane and glutaraldehyde. Optimization was carried out by Box-Behnken design and binding was confirmed by SEM, AFM, FTIR and fluorescence microscopy. Predicted optimum immobilization efficiency (88.64%) was very close to actual (87.98%), which confirmed the success of the immobilization process. The immobilized enzyme showed maximum activity at pH 5.0 and 57 °C, whereas Km and Vmax were found to be 6.40 mg/mL and 714.28 µmol/min/mg, respectively. The enzyme retained 75% activity after 12 uses at 30 °C. Increased values of ΔG° ΔH°, half-life and activation energy of the enzyme inactivation (ΔEd) revealed that thermo-stability increases after immobilization and the process followed first-order kinetics (r2 > 0.96). The activation energy of catalysis (ΔEa) and ΔEd for immobilized enzyme were 22.58 and 158.99 ± 1.10 kJ/mol, respectively which revealed that denaturation of the enzyme requires a higher amount of energy rather than catalysis. Thermodynamic and fluorescence spectroscopic studies revealed that the process is non-spontaneous (ΔG > 0) and endothermic (ΔH > 0) and occurred through protein unfolding rather than aggregation (ΔS > 0). Thus increase in thermo-stability of immobilized fenugreek ß-amylase and non-toxic nature of GQDs could be exploited for maltose production in beverage, food and pharmaceutical industries.
Assuntos
Enzimas Imobilizadas/metabolismo , Grafite/química , Pontos Quânticos/química , Trigonella/enzimologia , beta-Amilase/metabolismo , Estabilidade Enzimática , Germinação , Concentração de Íons de Hidrogênio , Cinética , Pontos Quânticos/ultraestrutura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , TermodinâmicaRESUMO
Atomically thin metallic alloys are receiving increased attention due to their prospective applications as interconnects/contacts in two-dimensional (2D) circuits, sensors, and catalysts, among others. In this work, we demonstrate an easily scalable technique for the synthesis of 2D metallic alloys from their 3D quasicrystalline precursors. We have used aluminum (Al)-based single-phase decagonal quasicrystal Al66Co17Cu17 alloy to extract the corresponding 2D alloy structure. The 2D layered Al alloy possesses 2-fold decagonal quasicrystalline symmetry and consists of two- or three-layer-thick sheets with a lateral dimension of microns. These 2D metallic layers were combined with the atomic layers of tungsten disulfide to form the stacked heterostructures, which is demonstrated to be a stable and efficient catalyst for hydrogen evolution reaction.
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Multi-walled carbon nanotubes (MWNTs)-polyacrylamide (PAM) composites have been prepared using as purified, with ball milling and functionalized MWNTs by solution cast technique and characterized through scanning electron microscopy (SEM) and transmission electron microscopy (TEM). A comparative study has been made on the electrical property of these MWNTs-PAM composites with different MWNTs loadings. It has been shown that the ball milling and functionalization of MWNTs improves the dispersion of MWNTs into the polymer matrix. As the MWNTs loading increases from 0 to 40 wt% electrical conductivity of composite film increases by approximately 7 orders of magnitude whereas the electrical conductivity of functionalized composite film increases only approximately 4 orders of magnitude with respect to the pure PAM film. A model based on power law percolation for the electronic behavior of above composite has been developed and shows good agreement with the experimental data.
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In the present work, aligned TiO2 nanotubes have been synthesized by a simple method of electrochemical anodization of high purity, well cleaned, etched and ultrasonicated Ti-sheet (Purity approximately 99.99%) in a fluoride mediated electrolytic media consisting of a solution of 0.14 M NaF and a solution of 0.5 M/1.0 M H3PO4. Studies on the effects of anodization voltage, time and electrolyte concentration on the formation of TiO2 nanotubes have been carried out. The TiO2 nanotube arrays have been synthesized at applied anodization voltages of approximately 10 V and approximately 20 V. The anodization was carried out for 1 hour and 2 hours at each applied voltage. Structural/microstructural characterizations of TiO2 nanotubes have been carried out through scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM images of TiO, nanotubes showed interesting features relating to morphology, the pore size (diameter of the tubes) and the lengths of the tube. TEM investigations revealed that the as synthesized nanotubes are amorphous in nature and on electron beam annealing, these transformed to crystalline phases (rutile and brookite). The optical characterizations through UV-Visible spectroscopy exhibited that the band gap are approximately 3.03 eV and approximately 2.87 eV for tubes synthesized at applied anodization voltages of approximately 10 V and approximately 20 V respectively. A tentative mechanism for the growth of TiO2 nanotube has been put forward.
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A nano decagonal quasicrystalline phase in the Al70Cu10Co5Ni15 alloy has been synthesized by mechanical alloying of a mixture of elemental powders followed by annealing. A high-energy ball milling of the elemental mixture of Al, Cu, Co and Ni leads to the formation of B2 type quaternary intermetallic alloys. The X-ray diffraction and transmission electron microscopy techniques have been employed for characterization of the samples. It was observed that the dissolution of the individual elements into an alloy led to the formation of a nano B2 phase. This phase was found to be quite stable against milling and no other crystalline or amorphous phases could be detected. Milled powder after annealing at 700 degrees C for 60 h was found to transform to nano-decagonal phase. Attempts have been made to understand the evolution of the complex intermetallic nano phases and their relative stability during milling.
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The present study deals with the material tailoring of Mg(NH2)2-2LiH through dual borohydrides: the reactive LiBH4 and the non-reactive NaBH4. Furthermore, a pulverizer, as well as a catalyst FeTi, has been added in order to facilitate hydrogen sorption. Addition of LiBH4 to LiNH2 in a 1 : 3 molar ratio leads to the formation of Li4(BH4)(NH2)3 which also acts as a catalyst. However, the addition of NaBH4 doesn't lead to any compound formation but shows a catalytic effect. The onset dehydrogenation temperature of thermally treated Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4) is 142 °C as against 196 °C for the basic material Mg(NH2)2-2LiH. However, with the FeTi catalyzed Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4, it has been reduced to 120 °C. This is better than other similar amide/hydride composites where it is 149 °C (when the basic material is catalyzed with LiBH4). The FeTi catalyzed Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4 sample shows better de/re-hydrogenation kinetics as it desorbs 3.9 ± 0.04 wt% and absorbs nearly 4.1 ± 0.04 wt% both within 30 min at 170 °C (with the H2 pressure being 0.1 MPa for desorption and 7 MPa for absorption). The eventual hydrogen storage capacity of Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4 together with FeTi has been found to be â¼5.0 wt%. To make the effect of catalysts intelligible, we have put forward in a schematic way the role of Li and Na borohydrides with FeTi for improving the hydrogen sorption properties of Mg(NH2)2-2LiH.
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The perovskite manganites with generic formula RE(1-x)AE(x)MnO(3) (RE = rare earth, AE = Ca, Sr, Ba and Pb) have drawn considerable attention, especially following the discovery of colossal magnetoresistance (CMR). The most fundamental property of these materials is strong correlation between structure, transport and magnetic properties. They exhibit extraordinary large magnetoresistance named CMR in the vicinity of the insulator-metal/paramagnetic-ferromagnetic transition at relatively large applied magnetic fields. However, for applied aspects, occurrence of significant CMR at low applied magnetic fields would be required. This review consists of two sections: in the first section we have extensively reviewed the salient features, e.g. structure, phase diagram, double-exchange mechanism, Jahn-Teller effect, different types of ordering and phase separation of CMR manganites. The second is devoted to an overview of experimental results on CMR and related magnetotransport characteristics at low magnetic fields for various doped manganites having natural grain boundaries such as polycrystalline, nanocrystalline bulk and films, manganite-based composites and intrinsically layered manganites, and artificial grain boundaries such as bicrystal, step-edge and laser-patterned junctions. Some other potential magnetoresistive materials, e.g. pyrochlores, chalcogenides, ruthenates, diluted magnetic semiconductors, magnetic tunnel junctions, nanocontacts etc, are also briefly dealt with. The review concludes with an overview of grain-boundary-induced low field magnetotransport behavior and prospects for possible applications.
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Stability of enzymes is an important parameter for their industrial applicability. Here, we report successful immobilization of ß-amylase (bamyl) from peanut (Arachis hypogaea) onto Graphene oxide-carbon nanotube composite (GO-CNT), Graphene oxide nanosheets (GO) and Iron oxide nanoparticles (Fe3O4). The Box-Behnken Design of Response Surface Methodology (RSM) was used which optimized parameters affecting immobilization and gave 90%, 88% and 71% immobilization efficiency, respectively, for the above matrices. ß-Amylase immobilization onto GO-CNT (bamyl@GO-CNT) and Fe3O4 (bamyl@Fe3O4), resulted into approximately 70% retention of activity at 65⯰C after 100â¯min of exposure. We used atomic force microscopy (AFM), scanning and transmission electron microscopy (SEM and TEM), Fourier transformed infrared (FT-IR) spectroscopy and fluorescence microscopy for characterization of free and enzyme bound nanostructures (NS). Due to the non-toxic nature of immobilization matrices and simple but elegant immobilization procedure, these may have potential utility as industrial biocatalysts for production of maltose.
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Arachis/enzimologia , Biocatálise , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Nanoestruturas/química , beta-Amilase/química , beta-Amilase/metabolismo , Estabilidade Enzimática , Grafite/química , Concentração de Íons de Hidrogênio , Indústrias , Cinética , Reciclagem , TemperaturaRESUMO
We report the exotic photoluminescence (PL) behaviour of 3D topological insulator Bi2Te3 single crystals grown by customized self-flux method and mechanically exfoliated few layers (18 ± 2 nm)/thin flakes obtained by standard scotch tape method from as grown Bi2Te3 crystals. The experimental PL studies on bulk single crystal and mechanically exfoliated few layers of Bi2Te3 evidenced a broad red emission in the visible region from 600-690 nm upon 375 nm excitation wavelength corresponding to optical band gap of 2 eV. These findings are in good agreement with our theoretical results obtained using the ab initio density functional theory framework. Interestingly, the observed optical band gap is several times larger than the known electronic band gap of ~0.15 eV. The experimentally observed 2 eV optical band gap in the visible region for bulk as well as for mechanically exfoliated few layers Bi2Te3 single crystals clearly rules out the quantum confinement effects in the investigated samples which are well known in the 2D systems like MoS2,WS2, WSe2, and MoSe2 for 1-3 layers.
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ZnO nanotetrapods and nanorods have been synthesized by a simple thermal evaporation of Zn powder (300 mesh, 99.99% purity) under simultaneous flow of oxygen and argon gases in two-zone furnace in two different temperature regions. These ZnO nanostructures have hexagonal structure, which grow along the [001] direction in the form of nanotetrapods (diameter approximately 60-150 nm, length approximately 1-4 microm) and nanorods (diameter approximately 30-60 nm, length approximately 2-5 microm). The morphologies of these ZnO nanostructures have been investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It has been found that growth parameters like temperature, gas flow rate etc., control the diameter of the nanotetrapods and nanorods. These novel structures of ZnO nanorods and nanotetrapods may be attractive for optical and other nanodevices.
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Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Óxido de Zinco/química , Catálise , Gases/química , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Propriedades de SuperfícieRESUMO
The macroscopic coaxial carbon cylinders (dia. approximately 0.5 cm with varying lengths approximately 2-5 cm) consisting of aligned carbon nanotube (CNT) stacks have been prepared by spray pyrolysis of benzene-ferrocene solution in argon atmosphere at approximately 850 degrees C-900 degrees C temperature. The coaxial carbon cylinders of CNT stacks have been formed directly inside the quartz tube. We attempted to prepare superimposed multi carbon cylinder configurations, each consisting of ordered and aligned CNTs stacked over each other. For this, we have terminated the spray of precursor after run of about 25 minutes, for a short interval (approximately 5 min), and then the solution was sprayed again over the already deposited hot CNT stack. Gross structural characterization of CNTs was done through X-ray diffraction technique (XRD). Microstructural characterizations of as prepared coaxial carbon cylinders with CNT stacks were done by scanning electron microscopic (SEM) techniques. SEM studies show that the CNTs are well aligned along the periphery of the cross section of coaxial carbon cylinder, each consisting of CNTs of the type described in the above. Comparisons have been made between the present macroscopic coaxial carbon cylinders with CNT stacks studied earlier by several other workers. Plausible explanation for the synthesis of CNT stacks will be put forward.
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Cristalização/métodos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Aerossóis/química , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
In the present study, attempts have been made to synthesize the nano-crystalline (Co, Ni)Al2O4 spinel powders by ball milling and subsequent annealing. An alloy of Al70Co15Ni15, exhibiting the formation of a complex intermetallic compound known as decagonal quasicrystal is selected as the starting material for mechanical milling. It is interesting to note that this alloy is close to the stoichiometry of aluminum and transition metal atoms required to form the aluminate spinel. The milling was carried out in an attritor mill at 400 rpm for 40 hours with ball to powder ratio of 20 : 1 in hexane medium. Subsequent to this annealing was performed in an air ambience for 10, 20, and 40 h at 600 degrees C in side the furnace in order to oxidize the decagonal phase and finally to form the spinel structure. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the formation of nano-sized decagonal phase after milling and then (Co, Ni)Al2O4 spinel type phase after annealing. The XRD studies reveal the lattice parameter to be 8.075 angstroms and the lattice strain as 0.6%. The XRD and TEM explorations of spinel phase indicate the average grain size to be approximately 40 nm.
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Ligas/síntese química , Compostos de Alumínio/química , Óxido de Alumínio/síntese química , Cobalto/química , Óxido de Magnésio/síntese química , Nanoestruturas/química , Níquel/química , Ligas/química , Compostos de Alumínio/análise , Óxido de Alumínio/química , Cobalto/análise , Cristalização , Desenho de Equipamento , Hexanos/química , Temperatura Alta , Óxido de Magnésio/química , Microscopia Eletrônica de Transmissão , Nanoestruturas/análise , Nanoestruturas/ultraestrutura , Níquel/análise , Tamanho da Partícula , Difração de Pó , Solventes/química , Fatores de TempoRESUMO
In this article, we proposed a facile one-step synthesis of Fe3O4 nanoparticles of different shapes and sizes by co-precipitation of FeCl2 with piperidine. A careful investigation of TEM micrographs shows that the shape and size of nanoparticles can be tuned by varying the molarity of piperidine. XRD patterns match the standard phase of the spinal structure of Fe3O4 which confirms the formation of Fe3O4 nanoparticles. Transmission electron microscopy reveals that molar concentration of FeCl2 solution plays a significant role in determining the shape and size of Fe3O4 nanoparticles. Changes in the shape and sizes of Fe3O4 nanoparticles which are influenced by the molar concentration of FeCl2 can easily be explained with the help of surface free energy minimization principle. Further, to study the magnetic behavior of synthesized Fe3O4 nanoparticles, magnetization vs. magnetic field (M-H) and magnetization vs. temperature (M-T) measurements were carried out by using Physical Property Measurement System (PPMS). These results show systematic changes in various magnetic parameters like remanent magnetization (Mr), saturation magnetization (Ms), coercivity (Hc), and blocking temperature (T B) with shapes and sizes of Fe3O4. These variations of magnetic properties of different shaped Fe3O4 nanoparticles can be explained with surface effect and finite size effect.
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In search of affordable, flexible, lightweight, efficient and stable supercapacitors, metal oxides have been shown to provide high charge storage capacity but with poor cyclic stability due to structural damage occurring during the redox process. Here, we develop an efficient flexible supercapacitor obtained by carbonizing abundantly available and recyclable jute. The active material was synthesized from jute by a facile hydrothermal method and its electrochemical performance was further enhanced by chemical activation. Specific capacitance of 408 F/g at 1 mV/s using CV and 185 F/g at 500 mA/g using charge-discharge measurements with excellent flexibility (~100% retention in charge storage capacity on bending) were observed. The cyclic stability test confirmed no loss in the charge storage capacity of the electrode even after 5,000 charge-discharge measurements. In addition, a supercapacitor device fabricated using this carbonized jute showed promising specific capacitance of about 51 F/g, and improvement of over 60% in the charge storage capacity on increasing temperature from 5 to 75 °C. Based on these results, we propose that recycled jute should be considered for fabrication of high-performance flexible energy storage devices at extremely low cost.