Browsing by Author "Brijesh, K."

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Advanced Electrolyte Additives for Lithium-Ion Batteries: Classification, Function, and Future Directions
(American Chemical Society, 2025) Brijesh, K.; Jareer, M.; Lakshmi Sagar, G.; Mukesh, P.; Alagarsamy, A.; Mandal, D.; Nagaraja, H.S.; Shahgaldi, S.
Lithium-ion batteries (LIBs) are widely employed as energy storage devices, particularly in portable electronics and electric vehicles, owing to their high energy density and efficiency. Among the key components of LIBs, the electrolyte plays a crucial role in determining capacity, cycling stability, rate performance, the electrode/electrolyte interface, and overall battery efficiency. However, traditional electrolytes face significant challenges, including severe structural degradation and interfacial side reactions under high-voltage and high-temperature conditions. Protective layers, such as the cathode-electrolyte interphase (CEI) and solid-electrolyte interphase (SEI), are essential for addressing these issues. These layers inhibit electron transfer while allowing lithium-ion (Li+) transport, preserving the structural and electrochemical integrity of the battery. A cost-effective strategy to further enhance the electrode-electrolyte interface and boost LIB performance is the incorporation of carefully designed electrolyte additives. While some articles discuss the use of electrolyte additives in LIBs, there is a lack of detailed studies classifying these additives based on their chemical composition-based grouping. Such a classification enables a more focused examination of the roles and mechanisms by which these additives improve LIB performance. This review paper bridges this gap by examining various electrolyte additives and their contributions to enhancing the safety and performance of next-generation LIBs. It provides valuable insights into the current progress and challenges associated with additives in liquid electrolytes. The article is organized into seven sections, addressing boron-based electrolyte additives (Section 2), sulfur-based electrolyte additives (Section 3), phosphorus-based electrolyte additives (Section 4), fluorine-based electrolyte additives (Section 5), and nitrogen-based electrolyte additives (Section 6). Each section discusses specific examples, the formation of SEI and CEI layers, and the electrochemical properties of these additives. Furthermore, the article concludes with a summary and outlook, advocating for continued advancements in electrolyte engineering for LIBs. © 2025 American Chemical Society.
Chemically prepared Polypyrrole/ZnWO 4 nanocomposite electrodes for electrocatalytic water splitting
(2019) Brijesh, K.; Bindu, K.; Shanbhag, D.; Nagaraja, H.S.
ZnWO 4 , PPy, and PPy/ZnWO 4 nanoparticles were prepared using chemical synthesis. The structural, compositional and morphological properties of the prepared samples have been investigated using XRD, FTIR, SEM, and HRTEM respectively. The powder XRD reveals the monoclinic wolframite structure for both ZnWO 4 and PPy/ZnWO 4 nanocomposite. SEM confirms the wrapping of ZnWO 4 with PPy. The electrodes of ZnWO 4 , PPy, and PPy/ZnWO 4 have been tested as bifunctional electrocatalyst towards HER and OER using constant current chronopotentiometry (CP) and Linear Sweep Voltammetry (LSV). The electrochemical surface area and the electrocatalytic activity PPy/ZnWO 4 nanocomposite towards HER and OER are greater than that of pure ZnWO 4 and PPy. The Tafel slope of PPy/ZnWO 4 nanocomposite is 76 and 84 mV dec ?1 in 0.5 M H 2 SO 4 and 1 M KOH at room temperature for HER and OER respectively. The results suggest that PPy/ZnWO 4 nanocomposite is a good candidate for the bifunctional electrocatalyst for water splitting. 2018 Hydrogen Energy Publications LLC
Chemically prepared Polypyrrole/ZnWO 4 nanocomposite electrodes for electrocatalytic water splitting
(Elsevier Ltd, 2019) Brijesh, K.; Bindu, K.; Shanbhag, D.; Nagaraja, H.S.
ZnWO 4 , PPy, and PPy/ZnWO 4 nanoparticles were prepared using chemical synthesis. The structural, compositional and morphological properties of the prepared samples have been investigated using XRD, FTIR, SEM, and HRTEM respectively. The powder XRD reveals the monoclinic wolframite structure for both ZnWO 4 and PPy/ZnWO 4 nanocomposite. SEM confirms the wrapping of ZnWO 4 with PPy. The electrodes of ZnWO 4 , PPy, and PPy/ZnWO 4 have been tested as bifunctional electrocatalyst towards HER and OER using constant current chronopotentiometry (CP) and Linear Sweep Voltammetry (LSV). The electrochemical surface area and the electrocatalytic activity PPy/ZnWO 4 nanocomposite towards HER and OER are greater than that of pure ZnWO 4 and PPy. The Tafel slope of PPy/ZnWO 4 nanocomposite is 76 and 84 mV dec ?1 in 0.5 M H 2 SO 4 and 1 M KOH at room temperature for HER and OER respectively. The results suggest that PPy/ZnWO 4 nanocomposite is a good candidate for the bifunctional electrocatalyst for water splitting. © 2018 Hydrogen Energy Publications LLC
Dual electrochemical application of r-GO wrapped ZnWO4/Sb nanocomposite
(2019) Brijesh, K.; Bindu, K.; Amudha, A.; Nagaraja, H.S.
ZnWO4/Sb nanorods and r-GO-ZnWO4/Sb nanocomposite have been prepared using a single step solvothermal method. The prepared nanocomposites have been characterized using x-ray diffractometer (XRD), Scanning Electron Microscope (SEM), High Resolution Transmission Electron Microscope (HR-TEM), Raman and Brunauer-Emmett-Teller (BET). The x-ray photoelectron spectroscopy (XPS) technique was used to determine the elemental composition of ZWS-5 (5 mg r-GO-ZnWO4/Sb) composite. The XRD reveals the monoclinic wolframite structure of ZnWO4/Sb and r-GO-ZnWO4/Sb. SEM and HRTEM confirms that the ZnWO4/Sb has been decorated on the r-GO sheets. The electrochemical performance of the prepared samples towards the Hydrogen Evolution Reaction (HER) and dopamine sensing has been tested using electrochemical techniques. Onset potential of 265 mV @10 mA cm-2, lower Tafel slope (95 mV dec-1), high electrochemical surface area (1383.216 m2g-1) and high specific site density (18.551 06 1021 g-1) of ZWS-5 reveals the high electrocatalytic activity of the composite towards HER. Chronoamperometric dopamine sensing shows that ZWS-5 has the superior sensing performance with highest specific sensitivity (723 ?A ?M-1 ?g-1), lowest limit of detection (0.9624 ?M), along with a good selectivity. Results suggest that the r-GO-ZnWO4/Sb nanocomposite is a good candidate for the HER and electrochemical dopamine sensor. The incorporation of r-GO nanosheets with ZnWO4/Sb (ZWS) nanorods enhances the specific and electrochemical surface area, which accounts for the high electrocatalytic activity of the composite. 2019 IOP Publishing Ltd.
Dual electrochemical application of r-GO wrapped ZnWO4/Sb nanocomposite
(Institute of Physics Publishing helen.craven@iop.org, 2019) Brijesh, K.; Bindu, K.; Amudha, A.; Nagaraja, H.S.
ZnWO4/Sb nanorods and r-GO-ZnWO4/Sb nanocomposite have been prepared using a single step solvothermal method. The prepared nanocomposites have been characterized using x-ray diffractometer (XRD), Scanning Electron Microscope (SEM), High Resolution Transmission Electron Microscope (HR-TEM), Raman and Brunauer-Emmett-Teller (BET). The x-ray photoelectron spectroscopy (XPS) technique was used to determine the elemental composition of ZWS-5 (5 mg r-GO-ZnWO4/Sb) composite. The XRD reveals the monoclinic wolframite structure of ZnWO4/Sb and r-GO-ZnWO4/Sb. SEM and HRTEM confirms that the ZnWO4/Sb has been decorated on the r-GO sheets. The electrochemical performance of the prepared samples towards the Hydrogen Evolution Reaction (HER) and dopamine sensing has been tested using electrochemical techniques. Onset potential of 265 mV @10 mA cm-2, lower Tafel slope (95 mV dec-1), high electrochemical surface area (1383.216 m2g-1) and high specific site density (18.551 06 × 1021 g-1) of ZWS-5 reveals the high electrocatalytic activity of the composite towards HER. Chronoamperometric dopamine sensing shows that ZWS-5 has the superior sensing performance with highest specific sensitivity (723 ?A ?M-1 ?g-1), lowest limit of detection (0.9624 ?M), along with a good selectivity. Results suggest that the r-GO-ZnWO4/Sb nanocomposite is a good candidate for the HER and electrochemical dopamine sensor. The incorporation of r-GO nanosheets with ZnWO4/Sb (ZWS) nanorods enhances the specific and electrochemical surface area, which accounts for the high electrocatalytic activity of the composite. © 2019 IOP Publishing Ltd.
Dual storage mechanism of Bi2O3/Co3O4/MWCNT composite as an anode for lithium-ion battery and lithium-ion capacitor
(Elsevier B.V., 2024) Lakshmi Sagar, G.; Brijesh, K.; Mukesh, P.; Hegde, A.P.; Kumar, A.; Kumar, A.; Bhat, K.S.; Nagaraja, H.S.
Bismuth oxide(Bi2O3) and cobalt oxide(Co3O4) are promising owing to their unique properties, high storage capacity, low cost, and eco-friendliness, making them ideal for lithium-ion batteries(LIBs) and lithium-ion capacitors(LICs) anodes. This study presents the synthesis and thorough characterization of Bi2O3/Co3O4 and Bi2O3/Co3O4/MWCNT composites as potential LIB and LIC anode materials. The materials are synthesized using a hydrothermal process succeeded by annealing. Structural, morphological, and compositional studies were analyzed. Various tests evaluated electrochemical performance, including cyclic voltammetry(CV), confirming a dual storage mechanism like alloying and conversion reaction involved for better energy storage. Specific discharge capacities of 834 mAh/g and 1184 mAh/g were recorded for Bi2O3/Co3O4 and Bi2O3/Co3O4/MWCNT composite electrodes at a current density of 100 mA/g, respectively. The composite material exhibited notably enhanced rate capability, with 31 % and 51 % discharge capacities for Bi2O3/Co3O4 and Bi2O3/Co3O4/MWCNT, respectively. The cyclic stability assessment revealed that Bi2O3/Co3O4 and Bi2O3/Co3O4/MWCNT maintained a high coulombic efficiency of around 99 % over 250 charge–discharge cycles at a high current density of 1 A/g. The capacity retention was approximately 253 mAh/g for Bi2O3/Co3O4 and 439 mAh/g for the Bi2O3/Co3O4/MWCNT composite, indicating excellent cyclic stability and minimal energy loss during cycling. Moreover, the LICs assembly of Bi2O3/Co3O4/MWCNT//CB was investigated, revealing a power density of 200 W kg?1 alongside an energy density of 8.64 Wh kg?1. The cyclic stability assessment over 10,000 cycles exhibits a capacity retention of approximately 45 % under a high current density of 2 A/g. © 2024 Elsevier B.V.
Enhanced Electrochemical Performance of Low-Content Graphene Oxide in Porous Co3O4 Microsheets for Dual Applications of Lithium-Ion Battery Anode and Lithium-Ion Capacitor
(Springer, 2024) Lakshmi Sagar, G.; Brijesh, K.; Mukesh, P.; Amudha, A.; Bhat, K.S.; Nagaraja, H.S.
The enhancement of electrochemical performance in lithium-ion battery (LIB) anode materials through nanostructures is of paramount importance, facilitated by the synergistic integration of these unique architectures with active materials, which increases the availability of active sites and decreases the diffusion path for lithium ions. In this investigation, we successfully synthesized cobalt oxide (Co3O4) microsheets composed of small nanoparticles (measuring 28–33 nm), employing a straightforward hydrothermal process followed by annealing. Furthermore, to enhance the composite’s ability to endure volume changes and increase its electrical conductivity, we created a Co3O4/reduced graphene oxide (rGO) composite embedding a judicious amount of graphene oxide (GO). This engineered composite exhibited remarkable specific discharge capacity of 1081 mAh g−1 at 100 mA g−1, a substantial improvement over the pristine material’s capacity of 718 mAh g−1. The composite demonstrated reduced irreversible capacity loss relative to the pristine counterpart and approached a reversible capacity of nearly 99%. Even after 400 cycles under the demanding conditions of high current density of 500 mA g−1, the composite managed to retain 81% of its initial capacity, underscoring its exceptional cycling stability. Moreover, the application of the Co3O4/rGO//carbon black (CB) assembly in lithium-ion capacitors (LIC) yielded notable energy density of 15.6 Wh kg−1 at elevated power density of 1007 W kg−1. These LIC devices demonstrated robust cyclic stability across extended cycles, sustaining 56% of their initial capacity after 2000 cycles while operating at a current density of 2 A g−1. Graphical Abstract: [Figure not available: see fulltext.]. © 2024, The Minerals, Metals & Materials Society.
Enhancing conductivity of Bi2O3 through ‘Fe3+’ doping for pseudocapacitor application
(Springer Science and Business Media Deutschland GmbH, 2025) G, L.S.; Bhat, K.S.; Mukesh, P.; Hegde, A.P.; Kumar, A.; Brijesh, K.; Nagaraja, H.S.
Binary metal oxides have emerged as pSromising materials for advanced electrochemical energy storage systems due to their superior performance characteristics. In this study, we focus on bismuth oxide (Bi?O?), a material renowned for its high theoretical capacity, wide potential range, and exceptional power density, as a potential candidate for supercapacitors. Iron doping was employed as a strategy to enhance its electrochemical performance and modulate the band gap, thereby improving conductivity and charge storage efficiency. Fe-doped bismuth oxide (Fe-Bi?O?) was synthesized via a solvothermal method with varying iron concentrations (2%, 4%, and 6%), followed by annealing. The pure and iron-doped bismuth oxide samples revealed a combination of monoclinic and cubic phases and a prominent micro-sheet architecture. The introduction of iron doping led to a noticeable reduction in the band gap, highlighting its role in fine-tuning the electronic properties for enhanced energy storage capabilities. The electrochemical evaluation highlighted the 4% Fe-Bi?O? sample as the optimal composition, achieving a remarkable specific capacity of 904 F g?1, a substantial improvement over 101 F g?1 for pristine Bi?O?, at 1 A g?1 in a 2 M KOH electrolyte. Moreover, this sample exhibited outstanding cyclic stability, retaining 104 F g?1 after 2000 cycles at 10 A g?1. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.
Fabrication of AgWO4/CNT nanomaterial for high capacity lithium ion battery
(Taylor and Francis Ltd., 2022) Brijesh, K.; Prajil, M.K.; Nagaraja, H.S.
Herein, we report the synthesis of AgWO4 nanomaterial (AWN) and Single-walled carbon nanotube (SWCNT) wrapped AgWO4 nanomaterial (AWNC) via the solvothermal method and is used as an anode material for lithium-ion battery (LIB). The AWNC exhibits, 1202 mAh g?1 discharge capacity at 0.1 A g?1 current density with good cyclic stability and 100% columbic efficiency even after 500 cycles. The AWNC electrode shows a reversible capacity of 594, 521, 252, 143 and 84 mAh g?1 at 0.1, 0.2, 0.3, 0.5 and 1 A g?1 respectively. The 543 mAh g?1 reversible capacity recovered at 0.1 A g?1 after cycling at several current densities suggests the good rate performance of the AWNC electrode. The decent electrochemical performance of the AWNC is due to the synergetic effect between AgWO4 and SWCNT. AWNC shows improved rate capability, better cycling stability, reversible capacity and capacity retention than that of AWN. These results suggest that AWNC is an exciting anode material for LIB. © 2020 Informa UK Limited, trading as Taylor & Francis Group.
GeO2/ZnWO4@CNT nanocomposite as a novel anode material for lithium-ion battery
(Springer, 2020) Brijesh, K.; Nagaraja, H.S.
Single-walled carbon nanotube (SWCNT) wrapped GeO2/ZnWO4 nanocomposite was prepared by single-step solvothermal method. In this work, GeO2/ZnWO4 nanocomposites were prepared by varying the molar percentage of GeO2 and by further adding SWCNT for the composite to boost the electrochemical performance. The prepared GeO2/ZnWO4 nanocomposites and GeO2/ZnWO4@CNT nanocomposite are used as anode material for lithium-ion battery (LIB). As expected, GeO2/ZnWO4@CNT nanocomposite exhibits higher capacities and good rate capability than the GeO2/ZnWO4 nanocomposite. The GeO2/ZnWO4@CNT nanocomposite exhibits 930 mAh g?1 discharge capacity and 533 mAh g?1 charge capacity for the initial cycle at 100 mAh g?1 in the voltage range of 0.01–3 V (vs. Li+/Li). Even at high current density of 500 mAh g?1, GeO2/ZnWO4@CNT nanocomposite shows 231 mAh g?1 and 257 mAh g?1 charge/discharge capacity which are higher than that of GeO2/ZnWO4 nanocomposite. The GeO2/ZnWO4@CNT nanocomposite delivers 75.8% capacity retention and 100% coulombic efficiency even after 400 cycles at 300 mAh g?1. These results direct that GeO2/ZnWO4@CNT nanocomposite is a good negative electrode for lithium-ion battery. [Figure not available: see fulltext.]. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
High stable zinc tungstate electrode for electrochemical supercapacitor
(American Institute of Physics Inc. subs@aip.org, 2020) Dhanush, P.C.; Brijesh, K.; Vinayraj, S.
This paper aims to develop a way for synthesising Zinc Tungstate (ZnWO4) by Microwave method. Which is simpler easier and better than hydrothermal synthesis. Formation of the crystal microstructures were verified with the aid of Powder X-Ray Diffraction (XRD), and further, morphologies were investigated upon using Field Emission Scanning Electron Microscope (FESEM). The implications in the energy storage devices were examined by preparing a pseudo capacitor. The electrochemical characteristics were analysed by using three-electrode system and its performance was evaluated with the assistance of Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS). The result presented the specific capacitance as 79 Fg-1 for a scan rate of 1mVs-1. The ZnWO4 as an active material retains 96.52% stability up to 1000 cycles. A significant increase in the impedance for lower frequencies can be observed for the material after 1000 cycles when compared to that of the first cycle. Â© 2020 Author(s).
Impact of copper doping on the electrochemical response of MnSe2 as anode for lithium-ion battery
(Springer, 2024) Mukesh, P.; Lakshmi Sagar, G.; Brijesh, K.; Kumawat, S.; Hegde, A.; Kumar, A.; Nagaraja, H.S.
Transition Metal Chalcogenides (TMC), due to their unique physicochemical properties, are studied in various fields and have potent applications in energy storage applications. This work is based on the synthesis and characterization of copper-doped manganese di-selenide and the effect of its doping on electrochemical performance as anode material for lithium-ion battery applications using the solvothermal method. The characterization techniques used are X-ray diffraction, Raman spectroscopy, field-emission scanning electron microscopy, XPS, UV–visible absorption spectroscopy, and electrochemical analysis. The XRD data confirms the formation of MnSe2 exhibiting Cubic crystal geometry. The FESEM images show the micro-cube-like structure with agglomerated nanocluster nanostructures on the surface with a dimension of 100–200 nm. The doping of the copper has decreased the band gap of the MnSe2, as studied by the UV–visible absorption spectrum. The electrochemical performance is analyzed as anode material for lithium-ion batteries. The charge/discharge measurements show a specific capacity of 706 mAh g−1 as the initial discharge capacity and 336 mAh g−1 as the initial charge capacity at 0.1 A g−1 current density. Meanwhile, 3% Copper-doped MnSe2 showed a better specific capacity of 878 mAh g−1 as the initial discharge capacity and 461 mAh g−1 as the initial charge capacity at 0.1 A g−1 current density. Cyclic stability, rate capability, and electrochemical impedance spectroscopy were performed, and it shows that 3% copper-doped MnSe2 has good stability and better conductivity and charge kinetics, indicating copper doping has enhanced the electrochemical performance of pristine MnSe2. © The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024.
Lower Band Gap Sb/ZnWO4/r-GO Nanocomposite Based Supercapacitor Electrodes
(2019) Brijesh, K.; Nagaraja, H.S.
Sb/ZnWO4/r-GO nanocomposite has been prepared by a single step solvothermal method. The crystal structure of the prepared nanocomposite has been characterized using a powder x-ray diffractometer (XRD). The optical properties of the prepared nanocomposite were studied using UV visible spectroscopy and photoluminescence. The energy band gap of 3.52 eV is obtained for the ZWS-5 nanocomposite using Tauc plots. For both Sb/ZnWO4 and Sb/ZnWO4/r-GO nanocomposite XRD shows the monoclinic Wolframite structure. The supercapacitor performance of the prepared samples was carried out using electrochemical techniques such as cyclic voltammetry, galvanostatic charge discharge and electrochemical impedance spectroscopy. The nanocomposite ZWS-5 exhibits a specific capacitance of 102 F/g, which is higher than pristine ZWS specific capacitance of 64 F/g. Both ZWS and ZWS-5 electrodes show good capacitance retention proficiency even after 1000 cycles. 2019, The Minerals, Metals & Materials Society.
Lower Band Gap Sb/ZnWO4/r-GO Nanocomposite Based Supercapacitor Electrodes
(Springer New York LLC barbara.b.bertram@gsk.com, 2019) Brijesh, K.; Nagaraja, H.S.
Sb/ZnWO4/r-GO nanocomposite has been prepared by a single step solvothermal method. The crystal structure of the prepared nanocomposite has been characterized using a powder x-ray diffractometer (XRD). The optical properties of the prepared nanocomposite were studied using UV–visible spectroscopy and photoluminescence. The energy band gap of 3.52 eV is obtained for the ZWS-5 nanocomposite using Tauc plots. For both Sb/ZnWO4 and Sb/ZnWO4/r-GO nanocomposite XRD shows the monoclinic Wolframite structure. The supercapacitor performance of the prepared samples was carried out using electrochemical techniques such as cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The nanocomposite ZWS-5 exhibits a specific capacitance of 102 F/g, which is higher than pristine ZWS specific capacitance of 64 F/g. Both ZWS and ZWS-5 electrodes show good capacitance retention proficiency even after 1000 cycles. © 2019, The Minerals, Metals & Materials Society.
Monoclinic Wolframite ZnWO4/SiO2 nanocomposite as an anode material for lithium ion battery
(Elsevier B.V., 2020) Brijesh, K.; Dhanush, P.C.; Vinayraj, S.; Nagaraja, H.S.
Herein, we report the preparation and characterization of the ZnWO4 and ZnWO4/SiO2 nanocomposite. The ZnWO4/SiO2 nanocomposite exhibits 570 mAh g?1 discharge capacity and 314 mAh g?1 charge capacity at 10 mA g?1 for the primary cycle. The increasing amount of SiO2 in the ZnWO4/SiO2 nanocomposite increases the overall performance of the composite. The synergetic effect between the ZnWO4 and SiO2 enhances the rate capability, specific capacity, cycle stability and coloumbic efficiency of the composite. The good electrochemical performance of ZnWO4/SiO2 nanocomposite makes it a promising anode for Lithium ion battery. © 2020 Elsevier B.V.
Reinforcing NiO microsphere structural stability via amorphous carbon sheets obtained from waste milk for lithium-ion capacitor application
(Springer Science and Business Media B.V., 2025) Lakshmi Sagar, G.; Brijesh, K.; Mukesh, P.; Hegde, A.P.; Kumar, A.; Paliwal, A.; Bhat, K.S.; Nagaraja, H.S.
In the pursuit of sustainable chemistry and environmentally friendly energy storage, the study addressed the limitations of nickel oxide utilized as the active material for the anode in lithium-ion capacitors. Despite its abundance and favorable environmental properties, NiO suffered from significant volumetric expansion and slow electrochemical kinetics compared to carbon materials. To overcome these issues, amorphous carbon was extracted from spoiled waste milk through a simple combustion process, effectively converting biomass waste into renewable resources. The engineered NiO/amorphous carbon composite, synthesized through hydrothermal and annealing processes, mitigated the limitations of NiO. Field Emission Scanning Electron Microscopy confirmed the deposition of amorphous carbon sheets encasing NiO microspheres, which preserved structural integrity during electrochemical cycling. The amorphous carbon acted as a stabilizing matrix, encapsulating NiO microspheres to mitigate volumetric expansion and enhance lithium-ion transport kinetics. Electrochemical tests demonstrated a specific discharge capacity of 1230 mAh g?1 at a current density of 100 mA g?1, retaining 401 mAh g?1 after 1000 cycles at 1 A g?1, nearly doubling the retention performance of pristine NiO. Furthermore, the NiO/AC//AC lithium-ion capacitor achieved an energy density of 25.4 Wh kg?1 at a power density of 1991 W kg?1, maintaining 96% capacity after 3500 cycles. This study highlighted the potential of waste-derived carbon in developing high-performance, sustainable energy storage systems. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.
ZnWO4/r-GO nanocomposite as high capacity anode for lithium-ion battery
(2020) Brijesh, K.; Nagaraja, H.S.
The pristine ZnWO4 and ZnWO4/r-GO nanocomposite synthesized by the facile solvothermal method were tested as anode materials for lithium-ion battery. Ex situ X-ray photoelectron spectroscopy (XPS) confirms the elemental composition of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite. The ZnWO4/r-GO nanocomposite shows mesoporous nature and exhibits 50.802�m2�g?1 BET specific surface area, which is higher than that of pristine ZnWO4. In addition, the electrochemical property of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite investigated using 2032 half-cell reveals that GO enhances the electrochemical property of the ZnWO4. The ZnWO4/r-GO nanocomposite not only exhibits higher discharge capacity of 1158�mAh�g?1 at 100�mA�g?1 but also shows longer and stable cycle life at 300�mA�g?1 current density. The ZnWO4/r-GO nanocomposite exhibits 80.74% capacity retention even after 500�cycles. The synergetic effect of r-GO and ZnWO4 improves the capacity, columbic efficiency, and stability of the material. The results indicate that ZnWO4/r-GO nanocomposite is an interesting anode material for Li-ion battery with higher capacity complemented with stability compared to pristine ZnWO4. [Figure not available: see fulltext.]. � 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
ZnWO4/r-GO nanocomposite as high capacity anode for lithium-ion battery
(Springer, 2020) Brijesh, K.; Nagaraja, H.S.
The pristine ZnWO4 and ZnWO4/r-GO nanocomposite synthesized by the facile solvothermal method were tested as anode materials for lithium-ion battery. Ex situ X-ray photoelectron spectroscopy (XPS) confirms the elemental composition of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite. The ZnWO4/r-GO nanocomposite shows mesoporous nature and exhibits 50.802 m2 g?1 BET specific surface area, which is higher than that of pristine ZnWO4. In addition, the electrochemical property of the pristine ZnWO4 and ZnWO4/r-GO nanocomposite investigated using 2032 half-cell reveals that GO enhances the electrochemical property of the ZnWO4. The ZnWO4/r-GO nanocomposite not only exhibits higher discharge capacity of 1158 mAh g?1 at 100 mA g?1 but also shows longer and stable cycle life at 300 mA g?1 current density. The ZnWO4/r-GO nanocomposite exhibits 80.74% capacity retention even after 500 cycles. The synergetic effect of r-GO and ZnWO4 improves the capacity, columbic efficiency, and stability of the material. The results indicate that ZnWO4/r-GO nanocomposite is an interesting anode material for Li-ion battery with higher capacity complemented with stability compared to pristine ZnWO4. [Figure not available: see fulltext.]. © 2020, Springer-Verlag GmbH Germany, part of Springer Nature.
ZnWO4/SnO2 composite for supercapacitor applications
(Elsevier B.V., 2020) Vinayaraj, S.; Brijesh, K.; Dhanush, P.C.; Nagaraja, H.S.
The pristine ZnWO4 and ZnWO4/SnO2 composite was synthesized by solvothermal method. The crystal structure of the ZnWO4 and ZnWO4/SnO2 composite is determined by powder X-ray diffraction (XRD) pattern. The morphology of the samples investigated using SEM and found to be agglomerated structure. The samples are tested as an electrode material for supercapacitor using electrochemical techniques like cyclic Voltammetry (CV), Galvanostatic Charge-Discharge (GCD) and Electrochemical Impedance Spectroscopy (EIS). The ZnWO4/SnO2 composite reveals 56.7 F/g specific capacitance at 1 mV/s scan rate which is higher than that of pristine material and also ZnWO4/SnO2 composite exhibits good cyclic stability than pure ZnWO4. © 2020 Elsevier B.V.
ZnWO4/SnO2@r-GO nanocomposite as an anode material for high capacity lithium ion battery
(Elsevier Ltd, 2020) Brijesh, K.; Vinayraj, S.; Dhanush, P.C.; Bindu, K.; Nagaraja, H.S.
Lithium ion battery (LIB) is widely used energy storage device. Herein, we report the preparation of ZnWO4/SnO2 nanocomposite and ZnWO4/SnO2@r-GO nanocomposite via solvothermal method. The structural, elemental and morphological properties of the prepared samples are characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDAX), high-resolution transmission electron microscopy (HR-TEM), Brunauer-Emmett-Teller (BET) measurements, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) techniques. The prepared samples are tested as an anode for LIB. The ZnWO4/SnO2 (5%) nanocomposite delivers initial discharge capacity of 882 mAh g?1 at a current density of 100 mA g?1, while, the specific capacity increases with the increase of SnO2 upto 10% tested in present case. Further, ZnWO4/SnO2@r-GO nanocomposite exhibits a discharge capacity of 1486 mAh g?1 which is higher than that of ZnWO4/SnO2 nanocomposite. In addition, after 500 cycles ZnWO4/SnO2@r-GO nanocomposite exhibits 89.8% cycle life and 98% of discharge capacity retention. These results indicate that, ZnWO4/SnO2@r-GO nanocomposite is a promising anode material for LIB. © 2020 Elsevier Ltd