Browsing by Author "Samriddhi"

Now showing 1 - 6 of 6

A novel hybrid sodium ion capacitor based on Na [Ni0.60Mn0.35Co0.05] O2 battery type cathode and presodiated D-Ti3C2Tx pseudocapacitive anode
(Elsevier Ltd, 2024) Vikas Yadav; Anupam Patel; Anurag Tiwari; Samriddhi; Shitanshu Pratap Singh; Raghvendra Mishra; Rajendra K. Singh
The combination of the high-power density of supercapacitors and the high energy density of batteries makes hybrid sodium-ion capacitors (HSICs) a promising device. HSICs can provide better performance characteristics by harnessing both ion adsorption/desorption in the capacitor-type electrode and sodium-ion intercalation in the battery-type electrode. Here, the synthesis of MXene (Ti3C2Tx), a two-dimensional (2D) carbide and nitride is reported. Delaminated MXene (D-Ti3C2Tx) is a promising candidate for anode material in HSIC due to its large surface area (∼ 42 m2/g) and good electronic conductivity. Electrochemical study indicates that D-Ti3C2Tx anode exhibits a high discharge capacity of ∼213 mAh/g at a current rate of 20 mA/g. Further the presodiated D-Ti3C2Tx anode is paired with Na [Ni0.60Mn0.35Co0.05] O2 (P2-NMC) cathode to obtain the configuration of HSIC. The HSIC exhibits good specific capacitance of ∼187 F/g and specific discharge capacity of ∼110 mAh/g at a current density of 10 mA/g, according to the electrochemical analysis. A notable improvement in specific energy density (∼ 256 Wh/kg) and specific power density (∼579 W/kg) is also demonstrated by the HSIC. With P2-NMC being used as the cathode material rather than traditional activated carbon, there has been a rise in specific energy density. © 2024 Elsevier B.V.
Boosting sodium hybrid-ion capacitor performance via exfoliated Ti3C2TX (O/OH/F) anode and bio-derived activated hard carbon cathode
(Elsevier Ltd, 2025) Vikas G. Yadav; Anupam Patel; Anurag Tiwari; Samriddhi; Shitanshu Pratap Singh; Tanya Jaiswal; Rajendra K. Singh
The exfoliated MXene (eTCT) was synthesized from its parent MAX phase using a hydrofluoric acid-free etching system (HCl/LiF). The resulting eTCT sample exhibits a specific surface area of 51 m2 g−1 The fabricated eTCT electrode demonstrates remarkable electrochemical performance, delivering a high gravimetric specific discharge capacity of ∼280 mAh g−1 and an impressive specific capacitance of ∼385 F g−1, along with excellent rate capability. Cyclic voltammetry measurements reveal maximum specific capacitances of ∼730 F g−1 and ∼ 418 F g−1 at scan rates of 0.1 mV/s and 0.5 mV/s, respectively. After 150 cycles, the eTCT cell retains approximately 70 % of its initial discharge capacity, corresponding to a capacity fade rate of only 0.2 % per cycle. For energy storage applications. Further MXene's potential is explored by fabricating a sodium hybrid-ion capacitor (SHIC). Based on the total active mass of both electrodes, the SHIC achieves a gravimetric specific capacitance of 79 Fg−1. The eTCT//AMHC system demonstrates outstanding power and energy densities reaching ∼4.1 kW k g−1 and 156 Wh k g−1, respectively. These values surpass many lithium-based capacitors, highlighting the superior performance of MXene-based devices. The Wien2k calculations reveal that LiF-etched MXene exhibits enhanced electronic conductivity. Notably, MXene ([sbnd]F, -OH, [sbnd]O) show higher density of states (DOS) near the Fermi level compared to MAX phase, suggesting the enhancement in metallic character of MXene. Furthermore, the strong Na[sbnd]O interaction in Ti3C2O2 makes it particularly promising for sodium-ion storage applications. © 2025
Enhanced electrochemical performance of K0.67[Ni0.3Mn0.6Co0.1] O2 as a cathode material for secondary K-Ion batteries: Improved K-Ion insertion and reduced charge transfer barrier
(Elsevier B.V., 2024) Shitanshu Pratap Singh; Anupam Patel; Anurag Tiwari; Samriddhi; Vikas Yadav; Raghvendra Mishra; Rupesh Kumar Tiwari; Rajendra Kumar Singh
Potassium-ion batteries, with their high operating voltage and cost-efficiency, emerged as promising contenders for large-scale energy storage system. Nevertheless, the practical application is hindered by the significant challenges of achieving high capacity and good rate capability in cathodes. Herein, a novel layered oxide cathode, K0.67[Ni0.3Mn0.6Co0.1] O2 (KNMCO), has been synthesized via solid-state (S-KNMCO) and co-precipitation (C-KNMCO) routes. The X-Ray diffraction (XRD) peaks of KNMCO are identified in R3 m space group and well-indexed to hexagonal unit cell. The FE-SEM shows non-spherical morphologies for both samples. Additionally, high-resolution transmission electron microscopy (HR-TEM) images of the synthesized cathode materials shows the interlayer spacing of S-KNMCO is higher than that of C-KNMCO. Furthermore, the electrochemical performance of S-KNMCO and C-KNMCO is characterized using K-metal as anode and electrolyte KPF6 in EC/DEC (1:1, v/v). The S-KNMCO and C-KNMCO exhibit the maximum specific discharge capacity of ∼101 mAhg-1 and ∼66 mAhg-1 at the current rate of C/20 respectively. Additionally, these cells show the good rate capability and coulombic efficiency (∼94%). This research offers novel perspectives on the development of cathode substances for KIBs. © 2024 Elsevier B.V.
Hydrothermal assisted RGO wrapped fumed silica-sulfur composite for an advanced room-temperature sodium-sulfur battery
(Elsevier Ltd, 2024) Samriddhi; Anupam Patel; Anurag Tiwari; Shitanshu Pratap Singh; Vikas Yadav; Rupesh Kumar Tiwari; Rajendra Kumar Singh
A promising cathode material RGO/SiO2/S composite for an advanced room-temperature sodium‑sulfur (RT Na[sbnd]S) batteries is synthesized via incorporating nanosulfur into amorphous fumed silica wrapped with reduced graphene oxide (RGO) through the hydrothermal method. Fumed silica (SiO2) offers a high surface area beneficial for sulfur loading. In the presence of ethylenediamine (EDA), nanosulfur is incorporated into SiO2. Additionally, hydrothermal treatment of the prepared solution that contained EDA facilitates the optimal reduction of graphene oxide (GO) into nitrogen–doped interlinked, conducting, and porous RGO. EDA played a multifunctional role as nanosulfur precursor, a nitrogen source, as well as a reducing agent. The synthesized RGO/SiO2/S composite delivers a high initial discharge capacity of 923 mAh/g at 0.1 C-rate with excellent coulombic efficiency (∼99 %). During cycling, fumed silica in the composite buffers volume expansion that happens throughout the cycling process, while RGO in the composite enhances the conductivity of the sulfur. Additionally, the presence of nitrogen also improves the conductivity of the cathode material. © 2024 Elsevier Ltd
One-dimensional nanocomposites for renewable energies
(Elsevier, 2025) Samriddhi; Rajendra K. Singh
The seasonal, intermittent, and localized characteristics of renewable energy necessitate the design of efficient energy storage systems that can maximum its utilization. Electrochemical energy devices, such as batteries and supercapacitors, are gaining significant interest because of their diverse applications, that includes electronic devices, electric motors, and energy storage systems. The electrode material significantly influences the electrochemical performance of these devices, which includes superior safety, high energy/power density, and high capacity and stable cyclic performance. A considerable amount of research has been done to develop novel electrode materials with nanostructures that provide the necessary features for efficient electrochemical energy storage devices. These characteristics are large surface area, reduced ion diffusion and easy access to the electrolyte. This chapter explored the development of an one-dimensional nanocomposite as electrode for energy storage devices. © 2025 Elsevier Inc. All rights reserved.
Sponge-like porous sustainable hard carbon as an efficient anode for sodium-ion batteries
(Elsevier Ltd, 2025) Anupam Patel; Anurag Tiwari; Samriddhi; Shitanshu Pratap Singh; Vikas G. Yadav; Tanya Jaiswal; Danuta Kruk; Ranjith Krishna Pai; Rajendra K. Singh
Renewable, cost-effective, eco-friendly, and abundant biodegradable waste has emerged as a promising resource for developing hard carbon (HC) anode materials for rechargeable sodium-ion batteries (SIBs). This study focuses on synthesizing HC anode materials from mango leaves using hydrothermal carbonization process, and thereafter pyrolysis at 900 °C and 1000 °C. The synthesized HC shows the spongelike morphology along with large specific surface area (88.3 m² g−1). The resulting materials pyrolyzed at 900 °C and 1000 °C, designated as Mango (Mangifera indica) Leaves Hard Carbon (MLHC-900) and (MLHC-1000) respectively, deliver impressive discharge capacities per unit mass of approximately 241 mAh g−1 and 215 mAh g−1 at a current density of 10 mA g−1, respectively. After 1200 cycles at a current density 1000 mA g−1, the MLHC-900 demonstrated superior capacity retention compared to MLHC-1000. These results signify the potential of using biodegradable waste utilizing hydrothermal carbonization to fabricate efficient HC anodes for SIBs. © 2025 Elsevier Ltd