Physics - Research Publications
Permanent URI for this collectionhttps://kr.cup.edu.in/handle/32116/61
Browse
5 results
Search Results
Item Preparation and Energy Storage Assessment of Ti3C2 2d MXene and Its Possible Thinning Mechanism(Springer Nature, 2023-09-07T00:00:00) Singh, Diya; Rani, Pinki; Biswas, Sayani; Alegaonkar, Prashant S.Since after its discovery, MXene has captivated the focus of many researchers. In this work, we report on the low-temperature synthesis of Ti3AlC2 MAX phase at 800�? and its further etching to obtain Ti3C2 MXene. Initially, titanium (Ti), aluminium (Al), and graphite (C) precursors were taken in an appropriate volume proportion and add-mixed and grounded well via molten salt technique (Galvin et al. in J Eur Ceram Soc 38, 2018 [1]). The characterizations performed on powder such as FTIR, XRD, UV�Visible, SEM, and EDS confirmed Ti3AlC2 MAX phase. The MAX phase was subjected to the acid treatment (HF, concentration 40%) for ~ 80�h. The synthesized MXene was separated and investigated using FTIR, XRD, UV�Visible, SEM, and EDS techniques. The MXene was further employed to microwave treatment over the temperature 300�420�K at a discharge of power 120 W for 1�h. Analysis revealed that thickness of Ti3C2 layers is observed to be decreased with microwave treatment which can be a possible mechanism to obtain MXene quantum dots. In electrochemical analysis, specific capacitance for two electrode MXene@300�K and @400�K is reported to be 15 and 10�F/g, respectively, showing resistive nature of capacitance coupling for MXene. Analysis of electrochemical impedance spectroscopy together with bode showed the surface passivation effect of MXene layers to achieve different charge dynamics in both the systems. � 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item All-redox hybrid supercapacitors based on carbon modified stacked zinc cobaltite nanosheets(Royal Society of Chemistry, 2023-09-12T00:00:00) Kour, Simran; Kour, Pawanpreet; Sharma, A.L.The role of energy in the present century has increased with the fast advancement of the global economy. In this regard, hybrid supercapacitors (HSCs) as energy storage systems have become an extensive research focus worldwide. This study reports the synthesis of carbon-loaded ZnCo2O4 stacked nanosheets via an in situ hydrothermal process followed by annealing. The electrochemical response was tested in a 2-electrode system. The optimized composite exhibited a capacitance of ?527.6 F g?1 at 5 mV s?1. The symmetric SC (SSC) possessed an energy density (Ed) of ?17.3 W h kg?1 corresponding to a power density (Pd) of 2.25 kW kg?1. Two asymmetric all-redox HSCs have also been fabricated using an optimized composite material as the positive electrode. The previously synthesized MnCo2O4/AC (HSC1) and MnO2/AC (HSC2) were taken as negative electrodes. HSC1 exhibited an Ed of ?24.4 W h kg?1 corresponding to a Pd of ?0.8 kW kg?1. On the other hand, HSC2 exhibited the highest Ed of ?30.8 W h kg?1 at 2.4 kW kg?1. The real-time application of the composite is tested with the fabricated HSCs. HSC1 exhibited a capacitive retention of ?72.2% after 10 000 cycles. On the other hand, HSC2 exhibited a capacitive retention of ?73.4% after 10 000 cycles. The SSC, HSC1, and HSC2 illuminated a 39 red LED panel for ?3 min, 7 min, and 13 min, respectively. The results suggested the promising performance of all-redox HSCs. The overall results present a sustainable approach for creating hierarchical energy materials for the construction of future energy-storage systems. � 2023 The Royal Society of Chemistry.Item MoSe2-FeOOH nanocomposite as hybrid electrode material for high-performance symmetric supercapacitor(Elsevier Ltd, 2022-12-29T00:00:00) Tanwar, Shweta; Arya, Anil; Sharma, A.L.Molybdenum diselenide-based composite has been considered a potential material in the supercapacitor application due to its variable oxidation states, high surface area, and electronic conductivity. This report presents the composite formation of molybdenum diselenide nanoflowers and iron oxide-hydroxide nanorods utilizing a hydrothermal route assisted by room temperature chemical blending technique. The symmetric cell designed based on prepared composite material delivers the specific capacitance of 132 F g?1 for 1 A g?1 for a 1 V voltage. It shows 100% capacitance retention for 3000 cycles and 100% coulombic efficiency for 10,000 cycles at 1 A g?1. It provides an energy density of 18.3 Wh kg?1 at 1174 W kg?1 power density. The practical application associated with the designed symmetric cell based on the composite electrode was confirmed via the illumination of the panel comprising 42 red LEDs for 10 min effortlessly without break. Additionally, a self-proposed charge mechanism has been incorporated for an enhanced understanding of the reader. The improved results indicate the point that the prepared electrode material has good capability for high-performance supercapacitors. � 2022Item Electrochemical performance of mixed-phase 1T/2H MoS2 synthesized by conventional hydrothermal v/s microwave-assisted hydrothermal method for supercapacitor applications(Elsevier Ltd, 2022-07-05T00:00:00) Kour, Pawanpreet; Deeksha; Yadav, KamleshMixed-phase 1T/2H MoS2 has been receiving immense attention as an electrode material for supercapacitors due to the synergistic effects of both the phases. Herein, we synthesized mixed-phase 1T/2H MoS2 via two different techniques: conventional hydrothermal (HT) and microwave-assisted hydrothermal (MHT) technique. The formation of MoS2 is confirmed through X-ray diffraction pattern, scanning electron microscopy, energy dispersive X-ray spectroscopy, Raman-spectra, and X-ray photoelectron spectra. The electrochemical performance of the two samples is investigated using cyclic voltammetry (CV), Gravimetric charging-discharging (GCD) and electrochemical impedance spectroscopy (EIS). MoS2 synthesized via MHT method (MS-MW) and HT method (MS-HT) deliver capacitances of 421 F g?1 and 742 F g?1 at 5 mV s?1, respectively. The energy density of MS-HT (57 Wh kg?1) is almost double than that of MS-MW (30 Wh kg?1). MS-HT also exhibited remarkable capacitance retention of 91% over 1200 cycles, compared with MS-MW. The results demonstrate that MoS2 synthesized by the hydrothermal method delivers superior electrochemical performance. � 2022 Elsevier B.V.Item Synergistically modified WS2@PANI binary nanocomposite-based all-solid-state symmetric supercapacitor with high energy density(Royal Society of Chemistry, 2022-03-09T00:00:00) Iqbal, Muzahir; Saykar, Nilesh G.; Alegaonkar, Prashant S.; Mahapatra, Santosh K.The rapid development of intelligent, wearable, compact electronic equipment has triggered the need for durable, flexible, and lightweight portable energy storage devices. Nanomaterials that are capable of delivering the high specific power density and commensurate energy density are potential candidate for realizing such devices. Herein, we report the facile synthesis of a binary nanocomposite WS2@PANI by utilizing hydrothermal and physical blending techniques to assess it as an electrode material for high-performance supercapacitors. The nanocomposite electrode delivered specific capacitance >335 F g?1 @ 10 mV s?1 (two-electrode), achieving energy and power densities of ?80 W h kg?1 and ?800 W kg?1, respectively, with capacitance retention of 83% even after 5000 charge-discharge cycles @ 10 A g?1, all of which are superior to the WS2 electrode. Dunns model quantifies capacitive and intercalative contributions that showed the cumulative effect of both to realize a robust, cost-effective, and energy-efficient device. The strategically incorporated PANI broadened the electrochemical window and the device's overall performance, resulting in high specific energy density. We demonstrated that our all-solid-state symmetric supercapacitor could be used to illuminate a light-emitting diode and drive a rotary motor. We believe that our WS2@PANI binary nanocomposite will be a potential candidate for energy storage devices. � 2022 The Royal Society of Chemistry