Hybrid Mxene-li-ion battery Supercapacitor

Here's an abstract for the presentation titled "Integration of Mxene Supercapacitor and Li-ion Battery"

---

**Abstract**

The integration of Mxene supercapacitors and Li-ion batteries represents a promising advancement in energy storage technology, combining the high power density of supercapacitors with the high energy density of Li-ion batteries. This presentation explores the working principles, challenges, and potential solutions for enhancing the performance of these hybrid systems.

Mxenes, a class of two-dimensional materials comprising transition metal carbides, nitrides, and carbonitrides, exhibit unique properties such as high electrical conductivity, large specific surface area, and tunable surface chemistry, making them suitable for supercapacitor applications. However, issues such as aggregation, hydrophilicity, and synthesis challenges must be addressed to fully leverage their potential.

The presentation delves into various approaches to overcome the energy density limitations of traditional supercapacitors, including the use of asymmetric supercapacitors, graphene hybrids, and nanostructured materials. It also highlights the synthesis processes for Mxenes, comparing methods like hydrofluoric acid etching, fluoride salt etching, molten salt etching, ionic liquid etching, and electrochemical etching, along with their respective advantages and disadvantages.

A detailed comparison of Mxene supercapacitors, Li-ion batteries, and hybrid systems is provided, focusing on parameters such as capacitance, energy density, power density, cycle life, conductivity, and structural stability. The integration challenges, including electrolyte compatibility, electrode balancing, and safety concerns, are discussed, emphasizing the need for efficient and scalable synthesis techniques and a deeper understanding of charge storage mechanisms.

Finally, the future potential of Mxene-carbon hybrids for supercapacitors is explored, outlining prospective directions for research and development in this field. The findings presented underscore the significant role of Mxene-based hybrid systems in advancing energy storage solutions for applications requiring high power and energy density, such as portable electronics and electric vehicles.

1. MATL903:Recent development in Materials Seminar presentation on, “Integration of Mxene supercapacitor and Li-ion Battery” Student Name Student Id Viraj Solankure 7309296 Master of Engineering (Mechanical Engineering) FACULTY OF ENGINEERING AND INFORMATION SCIENCES

2. Introduction Supercapacitor working principal: Supercapacitor energy storage uses an electric double-layer capacitance created by charge separation at the electrolyte-bath solution interface to store electrical energy. Supercapacitors have two electrodes separated by an electrolyte, which is usually comprised of activated carbon. Ions from the electrolyte build up on the electrode surface when a voltage is applied, producing an electrical charge. Literature[6-9]: The problem is that it is a trade-off between the power and energy density of the current supercapacitors with the conventional batteries. Supercapacitors are less efficient at storing energy than deep chemical storage in batteries because they store energy on the surface of materials using electrostatic principles, which results in a low energy density. Because of this, they have a high-power density and are ideal for short energy bursts, but they have a poor energy density for long-term energy storage.

3. Important terminology : Energy density: The amount of energy a device holds is referred to as its energy density. E = ½ CV2 E: Energy provided by the supercapacitor C:Capacitance of the supercapacitor, V: Voltage of the supercapacitor. Power density: How fast the device could discharge its energy. P = E/t (P t = E) Where, t is the time. supercapacitors, which can be charged and discharged quickly, have a maximum storage capacity of around 5 Wh /kg. These numbers are far less than the 100-265 Wh /kg potentially provided by Lithium-ion batteries. This restriction was the one that negatively influenced the way the supercapacitor technology was being developed by targeting the enhancement of their energy density without affecting the intrinsic benefits of the supercapacitors, such as fast charging and cycle stability.

4. Different approaches to overcome the energy density problem: Asymmetric Supercapacitors: By combining materials with supportive qualities—such as conductive polymers' durability and TMOs' high capacitance—performance is enhanced by striking a balance between power and energy density. Graphene Hybrids: Energy density may be greatly increased by using graphene because of its enormous surface area and superior electrical conductivity, which enable larger charge storage per unit mass. Nanostructured Materials: Making use of the special qualities of materials at the nanoscale increases the surface area that may be used for storing charge, which raises energy density while preserving high power density. Hybrid supercapacitor: Combining with the charge storages, (such as lithium-ion capacitors) with supercapacitors can maximize their power density and enhance their energy density.

5. Approach 1: Hybrid system : MXene -carbon hybrid supercapacitor What is it ? A class of two-dimensional materials known as MXene is made up of carbonitrides, nitrides, or carbides of transition metals. Most promising Mxene material: Ti₃C₂T ₓ High Electrical Conductivity: effective charge transfer in the electrodes of supercapacitors. Large Specific Surface Area: graphene, can have a large specific surface area, which increases the number of charge storage sites. Good Hydrophilicity: facilitate simple interaction with organic and aqueous electrolytes, which is advantageous for the fabrication of electrodes. Tuneable Surface Chemistry: adjustable surface terminations enable customization of their electrochemical characteristics to meet needs. Challenges: Aggregation and restocking Hydrophilicity and stability Synthesis challenges Surface functionalization     Advantages and challenges with Mxene material[3]

6. Mxene synthesis process[3]: Synthesis Method Advantages Disadvantages Hydrofluoric Acid (HF) Etching - A tried-and-true technique - Generates superior MXenes - Utilizing extremely dangerous and caustic HF  - Producing hazardous waste - Limited scalability because of handling and disposing of HF Fluoride Salt Etching (MILD Method) - Less harmful than HF etching - Greater scalability - Continues to utilise substances containing fluoride Possibility of producing hazardous waste Molten Salt Etching Improved safety and environmental friendliness;-Removes the requirement for HF or fluoride-based etchants;-Offers the possibility of large-scale manufacture - By adjusting the salt composition, it permits surface functionalization. - Need for high temperatures - Difficulties in effectively removing salt - Restricted ability to modify MXene shape - Possible contamination from traces of contaminants in the molten salt Ionic Liquid Etching - Eco-friendly  - Properties that can be adjusted by changing the composition of the ionic liquid - Limited information and research Possible difficulties with cost-effectiveness and scaling up Electrochemical Etching - Potential for controlled etching and functionalization  - Milder conditions than HF etching - Relatively new method with limited research - Potential challenges in scalability and efficiency

7. Mxene supercapacitor with lithium-ion battery MXenes show characteristics similar to those of a capacitor but not quite like that of an ideal battery, suggesting their possible application in lithium-ion capacitors (LICs), which combine the best aspects of supercapacitors and batteries[1]. parameter Mxene Supercapacitor Mxene-liion battery Hybrid system Capacitance > 400 F/g High specific capacity (e.g., 1,000 mAh/g for some anodes) Increased capacitance in hybrid setups   Energy density Traditional supercapacitors: 5–10 Wh/kg 50 Wh/kg maximum (MXene hybrids)   Enhancement of energy density with MXene anodes   Possibility of combining battery energy density with supercapacitor power density   Power density incredibly high because of its quick charge and discharge times   moderate; usually less than that of supercapacitors   Hybrid systems retain high power density   Cycle life 90% or more of the capacity is retained after thousands of cycles.   Superior cycling stability with a capacity retention of over 90%   Enhanced cycling stability in hybrid systems Specific application High-power applications, portable electronics, and quick energy delivery   Portable gadgets, electric cars, and long-term energy storage           Electric cars, portable electronics, and applications needing considerable amounts of energy and power   Conductivity High conductivity because to the metallic character of MXene   Enhanced conductivity in anodes based on MXene   Enhanced overall system conductivity Structural stabilty Robust, stable electrochemical performance Improved structural stability with MXene composites High stability, combining the strengths of both technologies Statistical information of hybrid system,[4-5] Hybrid System Electrode Materials Specific Capacitance/ Capacity Energy Density Power Density Cycle Life MXene//LiFePO4 Lithium-ion Capacitor Ti3C2Tx MXene anode, LiFePO4 cathode 120 mAh/g (anode), 160 mAh/g (cathode) 116 Wh/kg 7.8 kW/kg 10,000 cycles (86% retention) MXene//MnO2 Hybrid Supercapacitor Ti3C2Tx MXene, MnO2 310 F/g (device) 44.6 Wh/kg 800 W/kg 5,000 cycles (92% retention) MXene//NiCo LDH Asymmetric Supercapacitor Ti3C2Tx MXene, NiCo LDH 120 F/g (device) 53.1 Wh/kg 800 W/kg 10,000 cycles (87% retention) Statistical information of hybrid system,[6-8]

8. Challenges with the integration[6,7,9]: Electrolyte compatibility: Selecting an appropriate electrolyte that offers a broad working voltage window and is compatible with both the MXene and lithium-ion electrodes can be difficult Structural integrity and longevity of cycling: One problem that needs to be addressed is ensuring the hybrid device's long-term structural stability and cycling life, especially at the interface between the two different electrode materials.   Electrode balancing: For LICs to function at their best and to prevent lithium plating problems, the capacities and operating potentials of the MXene supercapacitor electrode and the lithium-ion battery electrode must be balanced. Efficient and scalable synthesis: For practical applications, it is essential to develop scalable and economical synthesis techniques for creating high-quality MXenes and their composites. Knowing the processes of charge storage To further improve performance, a greater comprehension of the ion transport kinetics and charge storage mechanisms in the hybrid MXene -lithium-ion system is necessary. Safety concerns : Although MXenes have the potential to increase lithium-ion battery safety, thermal runaway problems still need to be addressed, particularly when combined with highly energy-density hybrid systems.

9. Future potential directions of MXene –carbon hybrids for supercapacitors[3]. Future scope:

10. References : Zhang X, Wang L, Liu W, Li C, Wang K, Ma Y. Recent Advances in MXenes for Lithium-Ion Capacitors. ACS Omega. 2019 Dec 18;5(1):75-82. doi : 10.1021/acsomega.9b03662. PMID: 31956753; PMCID: PMC6963900. A. Byeon   et al. , “Lithium-ion capacitors with 2D Nb2CTx ( MXene ) – carbon nanotube electrodes,”  Journal of Power Sources , vol. 326, pp. 686–694, Sep. 2016, doi : https://doi.org/10.1016/j.jpowsour.2016.03.066[2 ]. Pavithra N. K. Siddu , Sang Mun Jeong, and Chandra Sekhar Rout, “ MXene –carbon based hybrid materials for supercapacitor applications,”  Energy advances , vol. 3, no. 2, pp. 341–365, Jan. 2024, doi : https://doi.org/10.1039/d3ya00502j . L. Zhang, H. Tan, H. Zhu, K. Yang, W. Li, and L. Sun, “Layered CoS@NC   in situ  loaded onto Ti 3 C 2 T x   MXene as an efficient lithium-ion battery anode,”  Dalton transactions , Jan. 2024, doi : https://doi.org/10.1039/d3dt04005d . Z. Otgonbayar , S. Yang, I.-J. Kim, and W.-C. Oh, “Recent Advances in Two-Dimensional MXene for Supercapacitor Applications: Progress, Challenges, and Perspectives,”  Nanomaterials , vol. 13, no. 5, p. 919, Mar. 2023, doi : https://doi.org/10.3390/nano13050919 . R. Akhter and S. S. Maktedar , “ MXenes : A comprehensive review of synthesis, properties, and progress in supercapacitor applications,”  Journal of materiomics , vol. 9, no. 6, pp. 1196–1241, Nov. 2023, doi : https://doi.org/10.1016/j.jmat.2023.08.011 . X. Zhang, L. Wang, W. Liu, C. Li, K. Wang, and Y. Ma, “Recent Advances in MXenes for Lithium-Ion Capacitors,”  ACS omega , vol. 5, no. 1, pp. 75–82, Dec. 2019, doi : https://doi.org/10.1021/acsomega.9b03662 . S. Alam, Fizza Fiaz , Muhammad Ishaq Khan, Muhammad Zahir Iqbal, and Hosameldin Helmy Hegazy , “Recent advancements in the performance of MXene and its various composites as an electrode material in asymmetric supercapacitors,”  Journal of Alloys and Compounds , vol. 961, pp. 171007–171007, Oct. 2023, doi : https://doi.org/10.1016/j.jallcom.2023.171007 . Y. Li, Sowjanya Vallem , and J. Bae, “ MXene -based composites for high-performance and fire-safe lithium-ion battery,”  Current applied physics , vol. 53, pp. 142–164, Sep. 2023, doi : https://doi.org/10.1016/j.cap.2023.06.011. ‌ ‌