High-energy consumption in our day-to-day life can be balanced not only by harvesting pollution-free renewable energy sources, but also requires proper storage and distribution of energy. In this ...regard, lithium ion batteries are currently considered as effective energy storage devices and involve the most active research. There exist several review articles dealing with various sections of LIBs, such as the anode, the cathode, electrolytes, electrode-electrolyte interface
etc.
However, the anode is considered to be a crucial component affecting the performance of LIBs as evident from the tremendous amount of current research work carried out in this area. In the last few years, advancements have been focused more on the fabrication of the nanostructured anode owing to its special properties, such as high surface area, short Li
+
ion diffusion path length, high electron transportation rate
etc.
As the work in this area is growing very fast, the present review paper deliberates the recent developments of anode materials on the nanoscale. Different types of anode materials, such as carbon-based materials, alloys, Si-based materials, transition metal oxides, and transition metal chalcogenides, with their unique physical and electrochemical properties, are discussed. Various approaches to designing materials in the form of 0, 1 and 2D nanostructures and their effect of size and morphology on their performance as anode materials in LIBs are reviewed. Moreover, the article emphasizes smart approaches for making core-shell particles, nanoheterostructures, nanocomposites or nanohybrids with the combination of electrochemically active materials and conductive carbonaceous or electrochemically inactive materials to achieve LIBs with high capacity, high rate capability, and excellent cycling stability. We believe the review paper will provide an update for the reader regarding recent progress on nanostructured anode materials for LIBs.
High-energy consumption in our day-to-day life can be balanced not only by harvesting pollution-free renewable energy sources, but also requires proper storage and distribution of energy. In this regard, lithium ion batteries are currently considered as effective energy storage devices and are involved in the most active research.
The present work reports fabrication of trilaminar core–shell composites of Fe3O4@C@PANI as efficient lightweight electromagnetic wave absorber by facile hydrothermal method and subsequent ...high-temperature calcination followed by its encapsulation through oxidative polymerization of aniline. The prepared composite structure was characterized by FTIR, XRD, XPS, TEM, HRTEM, and SQUID. The measurement of reflection loss, complex permittivity, complex permeability, and total shielding efficiency of the composites has been carried out in the frequency range of 2–8 GHz. Our findings showed lowest reflection loss (∼33 dB) in composite comprised of Fe3O4@C:aniline (1:9 wt/wt) corresponding to shielding efficiency predominantly due to absorption (∼47 dB) than reflection (∼15 dB). Such high value of shielding efficiency could be ascribed to the presence of dual interfaces and dielectric–magnetic integration in Fe3O4@C@PANI. In all probability, higher dielectric loss through interface polarization and relaxation effects in Fe3O4@C@PANI could also contribute toward superior microwave absorption ability of Fe3O4@C@PANI compared to Fe3O4@C and Fe3O4/PANI binary composites. This is likely to enhance the interfacial polarization, natural resonance, dielectric polarization, trapping of EM waves by internal reflection, and effective anisotropy energy in Fe3O4@C@PANI.
The rapid increase in toxic dye wastewater generated from various industries remains a severe public health issue and prime environmental protection concern, posing a major challenge to existing ...conventional water treatment systems. Consequently, various physicochemical and biological treatment processes have been studied, which exhibit varying removal abilities depending on their experimental constraints. Among them, adsorption is considered to be the most efficient due to its high removal efficiency, easy operation, cost-effectiveness, and recyclability of the adsorbents. Considering this, the present review article focused on presenting a comprehensive summary of the various types of adsorbents such as commercial activated carbon, metal oxide-based, carbon-based, metal-organic framework, and polymer-based adsorbents used in dye remediation of contaminated water. The effects of several critical factors such as initial dye concentration, solution pH, temperature, and adsorbent dose on the dye adsorption performance are also described. In addition, the adsorption mechanisms responsible for dye removal are explained based on electrostatic attraction, ion exchange, surface complexation, and π-π interactions. Finally, critiques, future perspectives, and a summary of the present article are given. Various adsorbents such as carbon-based materials, metal oxides, bio-adsorbents, and polymer-based materials, have been shown to be efficient for the removal of dye pollutants from wastewater. Thus, it is anticipated that dye removal by adsorption can provide a feasible solution for the treatment of dye-laden water.
This review is focused on the origin of dye pollutants, their ecotoxicological effects and adsorptive removal using various types of adsorbents.
Among different metal chalcogenides, copper sulfides have been extensively studied in the past few years due to their semiconducting and non-toxic nature, making them useful in a wide range of ...applications from the energy to the biomedical fields. A series of stoichiometric compositions of copper sulfides from Cu-rich, Cu
2
S to Cu-deficient, CuS
2
exist with different crystal structures as well as phases, resulting in different unique properties. The suitable band gap values in the range of 1.2-1.5 eV and unique optoelectronic properties indicate that the material is photocatalytically active and exhibits excellent plasmonic behavior. The material is also known for promising thermoelectric properties, converting waste heat into electricity through the Seebeck effect. The nanodimensional form of copper sulfides promotes their use to a more advanced level, tuning their properties with the size of the materials. In view of this, the present review article is focused on the compositions, phases and crystal structures, and different synthetic methodologies involved in the fabrication of 0D, 1D and 2D nanostructured copper sulfides. Moreover, recent advancements on their use in various applications will also be briefly discussed.
Copper sulfides are the most extensively studied materials due to their non-toxicity, semiconducting nature and tunable properties. In view of this, present review article discusses various synthetic strategies for the fabrication of nanostructured copper sulfides of different morphologies and properties comprehensively followed by their applications in various fields.
The present work is focused on the protective-agent-free synthesis of interconnected copper cobaltite (Cu0.3Co2.7O4) nanochains by temperature-controlled solvothermal method followed by post-thermal ...treatment of the precursors. Furthermore, Cu0.3Co2.7O4 interconnected nanochains are employed as electrocatalyst for water oxidation in alkaline medium for the first time. Extensive studies of physiochemical properties showed the formation of interconnected 1D nanochains of Cu0.3Co2.7O4 exhibiting a larger specific surface area (139.5 m2 g–1) and enhanced electrochemical water oxidation ability. It delivered excellent mass activity (∼50.0 A g–1), high anodic current density (∼124.9 mA cm–2 at 1.75 V versus reversible hydrogen electrode), and turnover frequency (∼4.26 × 10–2 s–1) in 1.0 M KOH. These Cu0.3Co2.7O4 nanochains also demonstrated low overpotential (∼351 mV) and good cycling stability (1000 cycles) in strong alkaline media. The fabricated Cu0.3Co2.7O4 nanochains could be a good alternative to the commercial OER electrocatalysts (RuO2 and IrO2) and also advantageous to the development of efficient, cost-effective, and durable electrocatalysts for electrochemical water splitting.
Herein, we report an in situ reduction process of GO to rGO on Ni foam during deposition of Co3O4 nanoflakes via ammonia evaporation technique followed by thermal treatment. The synthesis procedure ...and the design of electrode make it very promising for supercapacitor application. The characteristic electrochemical properties indicate the ‘battery’ type material and supercapattery performances were investigated thoroughly. The electrode exhibited considerably high specific capacity of 1328 C g−1 at 2 A g−1 current density and showed good stability compared to Co3O4 nanoflakes deposited on bare Ni foam. The performance as asymmetric supercapacitor in a two-electrode configuration of Co3O4-rGO/Ni foam also revealed high specific capacitance of 80 F g−1 at current density of 0.1 A g−1 and excellent stability with 94.5% capacity retention after 10,000 cycles. A considerably high energy density of 20 Wh kg−1 at power density of 1200 W kg−1 was achieved for Co3O4-rGO/Ni foam based asymmetric device, confirming the material as a potential candidate for supercapacitor application.
We report an in situ reduction process of GO to rGO on Ni foam during deposition of Co3O4 nanoflakes via ammonia evaporation technique followed by thermal treatment. Such an arrangement exhibited a high performance asymmetric supercapacitor with great stability. Display omitted
•In-situ reduction of GO into rGO wrapped on Ni foam during deposition of Co3O4 nanoflakes.•The rGO/Co3O4 on Ni foam as nanohybrid electrode exhibited good supercapattery performance.•The asymmetric supercapacitor assemble shows exceptionally good specific capacitance with great cycling stability.•The device exhibits reasonably good energy as well as power density.
The present work is focused on fabrication of reduced graphene oxide/iron(II/III) oxide/polyaniline (RGO/Fe3O4/PANI) ternary composite by a hydrothermal method, its characterization, and application ...in the development of a high microwave absorbing shielding material. The RGO/Fe3O4/PANI composite showed dramatic enhancement of dielectric loss and magnetic loss compared to Fe3O4/PANI and RGO/Fe3O4 binary composites. This is ascribed to the embedment of more heterostructure phases. As a result, RGO/Fe3O4/PANI showed remarkably high SET (∼28 dB) through the absorption dominant mechanism. Our findings also showed maximum R L of Fe3O4/PANI, RGO/Fe3O4, and RGO/Fe3O4/PANI in the range of 2–8 GHz corresponding to −25 to −35, −40 to −46, and approximately −64 dB, respectively. This is in all probability due to the good impedance matching between permittivity/permeability and dielectric/magnetic losses.
This study is focused on the preparation of the CuS/RGO nanocomposite via the hydrothermal method using GO and Cu–DTO complex as precursors. X-ray diffraction, Fourier-transform infrared ...spectroscopy, and Raman and X-ray photoelectron spectroscopy study revealed the formation of the CuS/RGO nanocomposite with improved crystallinity, defective nanostructure, and the presence of the residual functional group in the RGO sheet. The morphological study displayed the transformation of CuS from nanowire to quantum dots with the incorporation of RGO. The galvanostatic charge/discharge curve showed that the CuS/RGO nanocomposite (12 wt % Cu–DTO complex) has tremendous and outperforming specific capacitance of 3058 F g–1 at 1 A g–1 current density with moderate cycling stability (∼60.3% after 1000 cycles at 10 A g–1). The as-prepared nanocomposite revealed excellent improvement in specific capacitance, cycling stability, Warburg impedance, and interfacial charge transfer resistance compared to neat CuS. The fabricated nanocomposites were also investigated for their bulk DC electrical conductivity and EMI shielding ability. It was observed that the CuS/RGO nanocomposite (9 wt % Cu–DTO) exhibited a total electromagnetic shielding efficiency of 64 dB at 2.3 GHz following absorption as a dominant shielding mechanism. Such a performance is ascribed to the presence of interconnected networks and synergistic effects.
PDF
