Browsing by Author "Vikas G. Yadav"

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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
Desulfonylative halogenation of arene sulfonyl chlorides using N-halosuccinimides: Synthesis, molecular docking, and anti-Alzheimer activity
(Elsevier Ltd, 2025) Vikas G. Yadav; Rohit Kumar; Saripella Srikrishna; Virendra Prasad
Considering the significant biological potential of halogenated arenes, we developed a novel and eco-friendly method for accessing dihalogenated arenes via N-halosuccinimide-promoted desulfonylative halogenation of arenesulfonyl chlorides under metal-free conditions. In silico evaluations of selected compounds for amyloid-beta (Aβ) protein interactions identified compounds 1d and 2d as promising candidates, exhibiting strong binding potential and low toxicity in wild-type Oregon R flies. Furthermore, these compounds demonstrated significant neuroprotective activity in an Aβ-induced Alzheimer's disease model in Drosophila, emphasizing the need for further studies in higher organisms and detailed mechanistic investigations. © 2025 Elsevier Ltd
Metal-Free Desulfonylative and C-H Halogenation of Arenes: A Novel Approach for Haloarene Synthesis
(John Wiley and Sons Inc, 2025) Vikas G. Yadav; Rohit Kumar; Mitushree Ghosh; Ashvani Yadav; Virendra Prasad
We report a novel metal-free approach for the desulfonylative halogenation of aryl sulfonyl chlorides and the C-H halogenation of arenes. This strategy employs hypervalent iodine(III) as both an oxidant and a group transfer agent with tetrabutylammonium halides (TBAX) as a halide source. The method offers several key benefits, including the use of inexpensive and readily available reagents, simple reaction conditions, compatibility with air, and the absence of transition metals. © 2025 Wiley-VCH GmbH.
Regioselective sulfenylation of indoles using sulfonyl hydrazides: In silico design, DFT calculation, hirshfeld surface analysis, ADMET study, molecular docking and anticancer activity
(Elsevier B.V., 2025) Ashvani Yadav; Vishal K. Singh; Rohit Kumar; Vikas G. Yadav; Ashish Kumar Kushwaha; Vikas Kumar Rana; Ajay Kumar; Virendra Prasad
We report the design, synthesis, and anticancer evaluation of some novel indole thioethers, constructed via an efficient and regioselective sulfenylation of indoles with sulfonyl hydrazides, facilitated by KSCN. This method offers a valuable tool for the synthesis of a variety of indole thioethers under mild reaction conditions with good to excellent yields. Initially, the drug like properties of all compounds were evaluated. Subsequently, six lead compounds were subjected to molecular docking studies targeting the active site of the B-RAF protein (PDB ID: 1UWH). These compounds demonstrated strong interactions with key amino acid residues, including Lys482 (3.47 Å), Gln529 (3.28 Å), Thr528 (2.85 Å), Phe467 (2.85 Å), Gly95 (2.86 Å), Thr598 (3.30 Å), His538 (3.37 Å), Ser535 (3.22 Å), and Asn579 (3.43 Å), suggesting their potential as anticancer agents. DFT calculations of the novel thioethers revealed their energy gaps and binding affinities, while Hirshfeld surface analysis highlighted significant intermolecular interactions within their crystal structures. In vitro cell-based assays were conducted on selected compounds to assess their cytotoxicity against human cancer cell lines. The results suggest that extending the exposure duration beyond 24 h may uncover significant cytotoxic effects. In conclusion, these compounds exhibit promising potential as anticancer agents against the tested human cancer cell lines. © 2025 Elsevier B.V.
Regioselective Thiolation of Indole to Construct 3-Arylthioindoles
(Bentham Science Publishers, 2025) Ashvani Yadav; Rohit Kumar; Vikas G. Yadav; Mitushree Ghosh; Virendra Prasad
A practical and novel approach for the regioselective synthesis of 3-arylthioindole derivatives has been accomplished using a combination of indole substrates with p-toluene sulfonyl hydrazide. This methodology employs NIS as the oxidant and PPh3 as the reductant to give the desired 3-arylthioindoles in good to excellent yields. This method offers several advantages, including simplicity, operational ease, and broad substrate scope. © 2025 Bentham Science Publishers.
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