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Rapidly increasing demand for electrical energy due to unprecedented growth of electronic gadgets urges the research on developing innovative electrode materials for new age batteries and supercapacitors (SCs). Among various electrode materials for SCs, copper ferrite (CuFe2O4) is a cost-effective compound to make electrode materials for SC application owing to its expansive multifunctional physical and electrical properties. The nanoparticles of CuxZn1−xFe2O4 (x = 1, 0.9, 0.7, and 0.5) were synthesized via a facile and effective microwave combustion route. The effective inclusion of zinc on the surface morphology, size of the nanoparticles, elemental compositions, crystalline nature, and electrochemical properties of CuxZn1−xFe2O4 (x = 1, 0.9, 0.7, and 0.5) were examined by different analytical techniques. The electrochemical investigations reveal the highest specific capacitance of 1250 F g−1 for Cu0.9Zn0.1Fe2O4 which is 100% more than the bare copper ferrite. In addition, supercapacitor device in the form of an asymmetric type has been assembled with an aid of Cu0.9Zn0.1Fe2O4 electrodes, and an electrochemical performance of the same was investigated using cyclic voltammetry. The assembled device delivered an energy density of 188.75 W h kg−1 and a power density of 1249 W kg−1. The simple and cost-effective preparation procedure of CuxZn1−xFe2O4 with efficient electrochemical features increases the possibility of this material to be a promising electrode for supercapacitor. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of bismuth oxide (Bi2O3) nanoparticles with three different surfactants: Cetyl Trimethyl Ammonium Bromide (CTAB), Poly Ethylene Glycol (PEG), and Sodium Dodecyl Sulphate (SDS) and their different properties. In order to study the performance of Bi2O3 based materials as negative electrodes in supercapacitor applications, the electrochemical properties of the three samples were carried out. For the electrodes of bismuth oxide covered with CTAB, PEG, and SDS, the estimated rates of diffusion were determined to be 85.6 × 10− 12 cm2 s− 1, 24.4 × 10− 12 cm2 s− 1, and 1.2 × 10− 12 cm2 s− 1 respectively. The estimated specific capacity values for the samples BOC, BOP and BOS are 549.8 C g–1, 412.7 C g–1 and 84.1 C g–1 at 5 A g–1 respectively. When compared to PEG and SDS assisted samples, the sample that was synthesized using CTAB showed the highest specific capacity. The distinctive extended rod-like morphology of BOC can be reasoned for this drastic improvement in capacity. Furthermore, even at a greater current density of 10 Ag− 1, the CTAB assisted Bi2O3 sample showed remarkable rate performance, keeping 92% of its initial capacitance after 5000 continuous GCD cycles. This finding shows that BOC has good rate and stability properties for prospective high-power supercapacitor applications. Further, asymmetric type two electrode device was fabricated and it exhibits higher energy density of 29 WhKg− 1 with a power density of 3404 Wkg− 1. [ABSTRACT FROM AUTHOR]

In the recent years, the whole world is looking for better energy storage devices. Supercapacitors are among the most promising high-capacity energy storage devices. Manganese-based material has gained more importance among transition metals due to its cost, easy fabrication, and wide potential applications. Here, we report the synthesis of a novel MOF using metal centers, dicarboxylate ligand, and aminoterephthalic acid as a co-ligand {Mn-Ni-NH2(h2fipbb)}MOF. The synthesized material has a unique hierarchical morphology consisting of manganese and nickel connected with NH2 through h2fipbb ligand linkage, which is highly efficient for the permeation of the electrolyte and electron transfer. The {Mn-Ni-NH2(h2fipbb)}MOF shows an excellent specific capacitance of 711.60 F g−1 using 2 M KOH at a current density of 1 A g−1. The two electrode system material exhibits a high-power and energy density of 743.99 W kg−1 and 20.49 Wh kg−1, respectively. From the above results, the synthesized {Mn-Ni-NH2(h2fipbb)}MOF can be considered a promising material for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles are considered to be an important material due to their good mechanical stability, unique structure and catalytic properties. The hydrothermal method was followed along with rambutan (Nephelium lappaceum L.) fruit peel extract mixed with metal ions to prepare titanium dioxide (TiO2) nanorods. Though there are numerous similar works published in past decades, in comparison with those works, the novelty of this work is using rambutan fruit peel as a precipitation agent. The advantages of using such natural agents are that they are eco-friendly and economically feasible. The prepared TiO2 nanorods were co-cultured with human breast cancer cells (MDA-MB-231) and their cytotoxicity was evaluated. The morphology of the nanorods was analyzed through transmission electron microscopy. The average diameter of the TiO2 nanorods was found to be 70–90 nm. The anatase phase of the tetragonal structure was confirmed through X-ray diffraction analysis. The studies of the vibrational Raman active modes and optical properties confirmed the presence of TiO2. X-ray photoelectron spectroscopy binding energy of Ti2p3/2 determined as 460 eV and that of O1s determined as 532 eV confirmed the presence of TiO2. Cytotoxicity was analyzed using MDA-MB-231 and cell death was observed at 73.65 µg/ml. [ABSTRACT FROM AUTHOR]

Zinc vanadate (Zn3V2O8) rods have been prepared using easy and economical hydrothermal technique and are explored for supercapacitor electrode application. X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM) were analysed for the structure and morphology of the sample. The electrochemical performance of the Zn3V2O8 electrode was investigated using cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge–discharge test. The performance of Zn3V2O8 in water soluble electrolytes, such as K2SO4, Na2SO4 and KOH were analysed, and the results demonstrated unique double layer properties of the material. The electrode material tested in 0.5 M K2SO4 showed good supercapacitive performance in terms of specific capacitance and efficiency when compared to other electrolytes. We have obtained a specific capacitance of 213 F g−1 at current density of 1 A g−1. This electrode exhibits very less charge transfer resistance (3.3 Ω) in potassium sulphate electrolyte and is lower than other electrolytes. Moreover, Zn3V2O8 provided enhanced rate capacity, with (77%) of retention capacity for charge–discharge up to 1000 cycles. [ABSTRACT FROM AUTHOR]

Copper based derivatives such as CuO, CuS and CuSe2 nanostructures were synthesized employing hydrothermal growth for clean energy production. Three different unique morphologies of CuO, CuS and CuSe2 was observed respectively as hexagonal nanoplates, sharp edge rock like nanostructures and nanoflowers consists of well defined nanorods. Half cell electrochemical compartment was designed with the fabricated electrodes to explore oxygen evolution reaction (OER) activity. The highest electrochemical performance was interestingly achieved from cyclic voltametry (CV) profile for CuSe2 electrode as 1144 F/g at 10 mV/s which is quite high specific capacitance for metal selenide candidate and also the higher OER activity of CuSe2 electrode of 735 mA/g current density at 10 mV/s with low overpotential of 252 mV has been attained. The higher electron transportation mechanism and excellent stability was also achieved for copper selenide candidate that could be recommended as efficient OER active catalysts for future clean energy production applications. [ABSTRACT FROM AUTHOR]

Mn3O4/MnSnO3 nanocomposites have been successfully synthesized via solvothermal method by using the mixed solution consisting of manganese chloride and tin chloride salt dissolved in the mixture of ethanol and deionized water in 50:50 ratio at the processing temperature of 180 °C by adapting different capping agents such as PVP, PVA and ethylene glycol. The synthesized Mn3O4/MnSnO3 nanocomposites were characterized by employing X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, photoluminescence spectra and scanning electron microscopy (SEM) studies. The obtained XRD spectra confirmed the formations of Mn3O4/MnSnO3 nanocomposite illustrated by the sharp predominant diffraction peak observed at 34.2° corresponding to the (021) lattice planes of Mn3O4. The SEM images supply the information about the morphology of synthesized Mn3O4/MnSnO3 nanocomposites. The sharp peaks observed at 483 cm−1 further characterize the presence of Mn–O stretching vibration bond in Mn3O4/MnSnO3 nanocomposite by employing Raman spectra. The PL result revealed the emissive nature of the sample. FTIR spectra observed at 625 cm−1 attributed to the characteristic peaks of Mn3O4/MnSnO3 nanocomposite. The Mn3O4/MnSnO3 nanocomposite synthesized by the assistance of PVP surfactant exhibits the high specific capacitance of 178.2 F g−1 at 0.5 Ag−1 current density which can be considered as potential candidate and excellent electrode for pseudocapacitors applications. [ABSTRACT FROM AUTHOR]

CuCo2O4 nanorods and their nanocomposites were prepared via facile hydrothermal synthesis with the help of urea. X-ray diffraction results revealed the face-centered cubic (Fd3m) structure and the obtained product average crystallite size was about 17.45 nm. The vibrational state of 1Eg and 1A1g Raman active modes of CuCo2O4 materials was observed at 480 and 609 cm−1. Scanning electron microscopy analysis revealed that the length of each CuCo2O4 nanorods is in the range of 30–40 µm with smooth surface. The role and the synergic effect of the prepared nanocomposite component were well-determined in electrochemical studies. The prepared CuCo2O4/AC/PANI nanocomposite specific capacitance was found to be 576.6 F g−1 at 0.5 A g−1 current density. When compared with CuCo2O4 nanorods (PM1) at 0.5 A g−1 current density, CuCo2O4/AC/PANI showed double increment in the specific capacitance. It is noteworthy that CuCo2O4/AC/PANI nanocomposite shows good specific capacitance of 198.1 F g−1 with high current density of 0.5 A g−1. Highlights: CuCo2O4/AC/PANI nanocomposite specific capacitance was found to be 576.6 F g−1 at 0.5 A g−1 current density. CuCo2O4/AC/PANI showed double increment in the specific capacitance. CuCo2O4/AC/PANI nanocomposite shows good specific capacitance of 198.1 F g−1 with a high current density of 0.5 A g−1. [ABSTRACT FROM AUTHOR]

The synthesis of bismuth based materials with porous structures for supercapacitor application has drawn much attention due to their high specific surface area and easy access of electrolytes with the electrode surface through their hierarchical pores. In this present report, we synthesized a three dimensional (3D) BiOCOOH micro flowers by a solvothermal approach and applied to supercapacitor applications. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy results confirmed that the formation of porous BiOCOOH flowers. When BiOCOOH was used as electrode material for supercapacitors it exhibits a maximum specific capacitance value of 312 F g−1 at current density of 1 Ag−1. Additionally, the BiOCOOH flowers retained 52% of its initial specific capacity after 5000 charge–discharge cycles indicating an excellent cyclic stability. This improvement in the cycle stability of the BiOCOOH is ascribed to high surface area and enhanced ion transport through the pores of the BiOCOOH flowers. This high specific capacitance and excellent cyclic stability of the porous BiOCOOH flowers prove to be a promising candidate for supercapacitor application. [ABSTRACT FROM AUTHOR]

Vanadium pentoxide (V2O5) based electrodes for energy storage devices have captured sizeable attention in the past decade owing to their attractive physiochemical features. In the present work, flaky structured V2O5 was prepared using a single step hydrothermal route. The results from analytical investigations hold up well with the formation scheme proposed. The flaky morphology of V2O5 facilitates additional pathways for electron transport and effective ion access. When employed as a supercapacitor electrode in a neutral electrolyte, this flaky V2O5 electrode demonstrates a specific capacitance of 472 F g−1. Besides, it retains maximum capacitance at higher current density confirming its good rate performance. An asymmetric type supercapacitor using flaky V2O5 as positive electrode and activated carbon as negative electrode exhibits specific capacitance of 69 F g−1. This device shows energy density of 10 W h kg−1 within the operational window of 1 V. [ABSTRACT FROM AUTHOR]

Zinc cobalt oxide (ZnCo2O4) microspheres are prepared at three different hydrothermal process temperatures (100 °C, 130 °C, and 160 °C) assisted with urea. XRD studies reveal the spinel face-centered cubic (Fd3m) structure of ZnCo2O4 microspheres. The optical and vibrational properties of the product are characterized by photoluminescence and FTIR studies. The strong near-band edge emission peak observed at 392 nm corresponds to the direct recombination of the exciton-exciton collision process for all three synthesized products; SEM analysis reveals the complete growth stage of spherical ZnCo2O4 microspheres at three different temperatures. The electrochemical properties of synthesized ZnCo2O4 microspheres are analyzed by cyclic voltammetry, electroimpedance spectroscopy, and galvanostatic charging and discharging studies. ZnCo2O4 microspheres (SH3-160 °C) exhibit the superior specific capacitance of 500 F/g at 0.75 A/g current density and retain their specific capacitance of 80% at current density 2 A/g. ZnCo2O4 microspheres (SH3-160 °C) may be considered as a good candidate as electrode in supercapacitor applications. [ABSTRACT FROM AUTHOR]

Detection of uric acid (UA) is a foremost area of research as abnormal increases in its level can be used to diagnose diseases such as gout, renal disorders, and arthritis. Development of efficient test diagnostics to detect UA in human urine is therefore required. In this study, magnesium oxide was prepared via a hydrothermal route. X-ray diffraction analysis revealed formation of amorphous cubic MgO. The transverse optical phonon mode of cubic MgO was confirmed at the zone center at ~ 479 cm−1. Emission peaks observed at 362 nm, 383 nm, 495 nm, and 521 nm showed the high-quality luminescent behavior of the undoped MgO. Scanning electron microscopy images confirmed formation of MgO microflowers. Cyclic voltammetry results confirmed the excellent electrocatalytic ability of Ni/Co-codoped MgO nanostructures. Chronoamperometry (CA) results confirmed that the synthesized Ni/Co-codoped MgO nanostructure possessed good stability under UA. Such transition-metal element-codoped MgO microflowers with improved performance could be suitable as an excellent tool for clinical diagnostics. [ABSTRACT FROM AUTHOR]

Metal-doped tin oxide is gathering interest in the field of energy storage and power supply devices, particularly in supercapacitors applications. In the present study, we adopt a hydrothermal method to synthesis SnO2, Zn-SnO2, Ag-SnO2 nanoparticles at suitable conditions of temperature, pH, reaction time, and capping agents (CTAB). SnO2, Zn-SnO2, Ag-SnO2 nanoparticles were synthesized at 160 °C for 12 h and characterized by employing X-ray Diffraction to confirm the regular crystalline formation with tetragonal structure. Initial analyses by employing CV and GCD results exhibited specific capacitance of 308.2 Ag−1 for Ag-SnO2 nanoparticles at current density 0.5 A/g and can be considered as suitable candidate as positive electrode for supercapacitor device applications. [ABSTRACT FROM AUTHOR]

NiO/NiSnO3 nanocomposite synthesis was accomplished by a hydrothermal method. The role of polyvinylpyrrolidone and experimental parameters in the configuration of NiO/NiSnO3 nanocomposite was studied by employing standard characterization techniques. Electrochemical properties were demonstrated by adopting cyclic voltammetry, electro-impedance spectra and galvanostatic charging and discharging studies. All the obtained products have contact resistance Rct of 0.72 Ω at low frequency arising from the resistance between the working electrode and the electrolyte. The NiO/NiSnO3 nanocomposite superior properties may arise from nanosized rod morphology due to their inherent properties having a significant impact on their electrochemical properties. The specific capacitance for RSA3 can be estimated as 524 F/g at a current density of 0.5 A/g. [ABSTRACT FROM AUTHOR]

Zinc doped tin oxide nanoparticles were synthesized by employing sol-gel method assisted with different surfactants namely cetyl trimethyl ammonium bromide (CTAB), hexamine and polyethylene glycol 400 (PEG-400). The synthesis of uniform distribution of spherical Zn-SnO2 nanoparticles in presence of PEG-400 was optimized. The synthesized Zn-SnO2 nanoparticles were characterized by employing standard characterization techniques. X-ray diffraction results confirmed the product high-quality crystalline formation. The photoluminescence peaks appeared at 360 nm revealed the recombination of electron and hole from band to band emission of SnO2 optical properties. The vibrational properties of Zn-SnO2 nanoparticles were confirmed by both Raman and infra red spectra. The spherical morphology and nano sized product was evident in 200 nm scale SEM images. The cyclic voltammetry result of the product Zn-SnO2 assisted PEG-400 exhibited the specific capacitance value of 312.7 F/g at scan rate of 10 mV/s and revealed the superior electrochemical properties. Moreover, the EIS and GCD studies also revealed the good supercapacitor nature with specific capacitance of 132.1 F/g at current density of 1 A/g for the product Zn-SnO2 (PEG-400).Diagrammatic representation of Zn doped SnO2 synthesis by sol-gel method with enhanced specific capacitance of 132.1 F/g at 1 A/g for Zn-SnO2 (PEG-400). Zn-SnO2 nanoparticles in presence of PEG-400 was optimizedZn-SnO2 (PEG-400) nanoparticles exhibits superior electrochemical propertiesProduct exhibits good capacitance (132.1 F/g) at 1 A/g current density [ABSTRACT FROM AUTHOR]

ZnO nanotips structure fabrication was undertaken through controlled growth by chemical vapor deposition (CVD) method. Substrate position and deposition time role was investigated systematically by controlling the parameters such as temperature, flow rate, and growth pressure. The obtained result showed that ZnO nanorods undergo a sharp regrowth process with increase in ZnO vapor availability in the CVD reactor. The surface morphology and structural properties were investigated by using field-emission scanning electron microscopy and X-ray diffraction (XRD) techniques. The grown nanostructures were used for gas sensor fabrication to detect and to study the sensitivity effects of H2 and CO. [ABSTRACT FROM AUTHOR]

The manuscript presents structural, optical and magnetic properties of CuFeO nanoparticles obtained employing a simple co-precipitation method in aqueous solution. Influence of ferric chloride concentration on the structural, optical and magnetic properties of CuFeO nanoparticles was investigated. XRD results clearly revealed the spinel tetragonal copper ferrite structures. The observed characteristic Raman E, F and A phonon mode of vibrations revealed the tetragonal copper ferrite structures. The observed PL results explored inverse spinel copper ferrite emission peaks in the range of visible region. IR result revealed the metal oxygen intrinsic vibrations of octahedral and tetrahedral sites in the spinel copper ferrite structure. SEM analysis clearly revealed the spherical shape morphology particles sizes are in the nano scale range. VSM studies clearly revealed that copper ferrite exhibit weak ferromagnetic behaviour. It was found that the ferric chloride concentration added to copper chloride precursor in the ratio of 1:1, 1:2 and 1:3 during the synthesis process played a significant role in structural and magnetic properties of the obtained product. [ABSTRACT FROM AUTHOR]

Nickel-doped magnesium oxide (Ni-MgO) nanopowders were successfully synthesized by employing a simple sol-gel process by adopting different surfactants such as Hexamine, CTAB and PEG-400. XRD results clearly revealed the formation of face centered cubic structure. The characteristic PL peaks observed at 401, 490 and 552 nm are owing to charge transfer characteristic in surface state of the obtained product. The characteristic IR peaks observed at 445 and 854 cm could be attributed to Mg-O stretching vibration and the peak appeared at 1036 cm belongs to Mg-O vibrations modes. Scanning electron microscopy (SEM) results clearly revealed the uniform distribution of thin nanolayer morphology in different direction for Ni-MgO (CTAB) product, the mixture of nanolayer and nanoparticle configurations for Ni-MgO (Hexamine) product and more agglomerated particle formation for Ni-MgO (PEG-400) product. The electrochemical studies were carried out to estimate the specific capacitance of Ni-MgO (CTAB) product at low scan rate 10 mV/s which showed an excellent value of 360.5 F/g. The GCD studies for synthesized Ni-MgO (CTAB) nanolayer morphology have superior specific capacitance of 96 F/g at 1 A/g with the excellent specific capacitance. The materials stability for 5000 charging and discharging cycles retains 68% of the specific capacitance 83 F/g at current density of 5 A/g. [ABSTRACT FROM AUTHOR]

Hydrothermal method was adapted to synthesis NiCoO nanoparticles by varying nickel and cobalt precursor concentration as 1:1, 1:2, and 1:3 ratios. X-ray diffraction (XRD) results revealed the spinel NiCoO structure belongs to $${\rm{Fd}}\overline {\rm{3}} {\rm{m}}$$ space group system with face-centered cubic crystal structure. Raman characteristic peaks observed at 495 and 654 cm explored E and A modes of spinel NiCoO product. Photoluminescence (PL) results revealed the hole recombination of Ni/Co ions from 3d-E and 3d-T electronic state of spinel NiCoO material. The characteristic Fourier transform infrared spectroscopy (FTIR) metal-oxygen bands appeared at 658 and 558 cm revealed the spinel-type crystal structure. SEM image revealed the NiCoO spherical nanoparticles formation with an average particle size of around 500 nm. The cyclic voltammetry studies revealed the estimated average specific capacitance value of NC3 (NiCoO spherical nanoparticles) as 542 F g relatively higher than NC1 and NC2. The electro impendence spectroscopy results explored the small arc formation in high frequency range and very low charge transfer resistance ( R ), which resulted high conductive active materials. The estimated specific capacitance for NC3 exhibited superior galvanstatic charging and discharging (GCD) characteristics with high specific capacitance of 294 F g at high current density of 1 A g and revealed that the obtained electrode is suitable for supercapacitor applications. Graphical abstract: Hydrothermal synthesis using an excess of Co source leads to smaller and more uniform particle size. This particle size and the slightly larger crystallite size formed in the materials leads to the improved electrochemical performance of the particles. [ABSTRACT FROM AUTHOR]

Effect of different capping agents such as hexamine and PEG-400 on the synthesis of α-MoO nanoparticles was investigated employing a simple chemical reduction method by adopting NaBH as reducing agent. Owing to the general fact that the two capping agents are unique in chemical properties, different physico-chemical properties on the synthesized samples were expected. The impact of capping agents on crystallite size, structural, morphological and optical properties of the obtained product has been studied employing standard characterization techniques. X-ray diffraction analysis typically shows the formation of orthorhombic α-MoO nanoparticles with high crystalline nature. Raman studies also confirm the formation of α-MoO by exhibiting the characteristic Mo-O stretching and bending modes in the regions of 900-600 and 400-200 cm. PL and IR studies further ensured the formation of α-MoO nanoparticles. SEM image clearly revealed the nanoscale spherical morphology of synthesized α-MoO nanoparticles with and without capping agent. PEG-400 assisted α-MoO nanoparticles have demonstrated a good specific capacitance with 121 F/g as a suitable candidate for pseudo capacitance applications. [ABSTRACT FROM AUTHOR]

Hematite (α-FeO) nanoparticles are successfully synthesized by using the chemical reduction synthesis method. The obtained XRD results revealed the formation of rhombohedral crystal structure of hematite α-FeOwith Rc space group. Raman-forbidden LO E mode and E mode observed at 657, 409 and 285 are clearly revealed hematite α-FeO formation. The prominent PL peak observed at 576 nm is attributed to stronger 3d-4sp hybridization due to the impact of size and morphology effect on synthesized hematite (α-FeO) nanoparticles. SEM analysis revealed that the estimated average hematite nanoparticle size is reduced to be about 600-300 nm with an increase in the concentration of the reducing agent. The investigation of the magnetic properties of hematite nanoparticles showed that the product synthesized at low NaBH concentration exhibited an extremely small hysteresis loop and low coercivity when compared to higher concentrations. The influence of reducing agent concentration on the structure, morphology and ferromagnetic properties of hematite (α-FeO) nanoparticles are discussed comprehensively. [ABSTRACT FROM AUTHOR]

MnMoO4 nanoparticles were synthesized by employing solvothermal method at optimized experimental condition to explore their electrochemical properties. The fundamental characterization studies such as X-ray diffraction, Raman spectroscopy, and Fourier transform infrared spectra confirmed the formation of pure phase of monoclinic crystal structure with C2/m space group. X-ray photoelectron spectroscopy studies revealed that the core-level Mn-2p spectrum peaks observed at 641.2 eV can be attributed to Mn-2p3/2 and that at 654.1 eV can be indexed to the binding energy of Mn-2p5/2. Major infrared peaks observed at 725, 800, 867, and 946 cm−1 could be designated to the characteristics bands of tetrahedral MoO4 groups in MnMoO4 nanoparticles. Raman peaks observed at 351, 823, 886, and 932 cm−1 corresponded to characteristics bands for MnMoO4 nanoparticles. The cyclic voltammetry studies at different scan rates (i.e., 10, 20, 30, 50, 80, and 100 mV s−1) were performed for all three MnMoO4 nanoparticles and displayed similar redox peaks in the positive and negative current regions, reflecting the pseudocapacitive nature. From galvanostatic charge-discharge profiles, it was found that MnMoO4 nanorods (R2) show high- capacitance of 697.4 F g−1 at 0.5 A g−1 current density and 40% increment in specific capacitance than other nanoparticles and can be considered as suitable nanomaterials as electrode for energy storage applications. [ABSTRACT FROM AUTHOR]

Bismuth-based semiconductors have attracted significant attention in rechargeable batteries and supercapacitor devices. In this study, layered structured bismuth germanate (Bi12GeO20) was synthesized using hexamine as a surfactant, at 850 °C, and utilized as electro-active material for supercapacitor and sodium ion (NaB) storage applications. The physical characterization of the prepared Bi12GeO20 was studied with various characterization and microscopic analyses such as XRD, FT-IR, FESEM with EDS, HRTEM, and XPS analysis. The XRD analysis exposed the successful formation of a highly crystalline sillenite phase of Bi12GeO20. The surface morphology analysis FE-SEM and HR-TEM revealed the effective construction of the 2D layered structure of Bi12GeO20. The EDS results profound that uniform distribution of the Bi, Ge, and O elements with good elemental stoichiometry. The supercapacitor properties of the prepared Bi12GeO20 were evaluated with the help of three electrode method using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance (EIS) techniques in the aqueous solution of 3.0 M KOH. The prepared Bi12GeO20 architecture shows a higher specific capacitance of 355 F g−1, with a current density of 1 A g−1. Finally, the sodium-ion storage capacity of Bi12GeO20 was evaluated using a coin cell-type electrode. The as-synthesized Bi12GeO20 material was utilized as an anode for Na ion storage and demonstrated a high specific capacity of 740 mAh g−1 at 0.1 C rate. With these appreciable electrochemical performances, the single component Bi12GeO20 holds an ideal alternative electrode material to develop high-performance power and energy storage devices. [ABSTRACT FROM AUTHOR]