Pragati A. Shinde

Bio: Pragati A. Shinde is an academic researcher from University of Sharjah. The author has contributed to research in topics: Supercapacitor & Materials science. The author has an hindex of 16, co-authored 31 publications receiving 632 citations. Previous affiliations of Pragati A. Shinde include Shivaji University & Yonsei University.

Review on Recent Progress in the Development of Tungsten Oxide Based Electrodes for Electrochemical Energy Storage.

Abstract: Current progress in the advancement of energy-storage devices is the most important factor that will allow the scientific community to develop resources to meet the global energy demands of the 21st century. Nanostructured materials can be used as effective electrodes for energy-storage devices because they offer various promising features, including high surface-to-volume ratios, exceptional charge-transport features, and good physicochemical properties. Until now, the successful research frontrunners have focused on the preparation of positive electrode materials for energy-storage applications; nevertheless, the electrochemical performance of negative electrodes is less frequently reported. This review mainly focuses on the current progress in the development of tungsten oxide-based electrodes for energy-storage applications, primarily supercapacitors (SCs) and batteries. Tungsten is found in various stoichiometric and nonstoichiometric oxides. Among the different tungsten oxide materials, tungsten trioxide (WO3 ) has been intensively investigated as an electrode material for different applications because of its excellent charge-transport features, unique physicochemical properties, and good resistance to corrosion. Various WO3 composites, such as WO3 /carbon, WO3 /polymers, WO3 /metal oxides, and tungsten-based binary metal oxides, have been used for application in SCs and batteries. However, pristine WO3 suffers from a relatively low specific surface area and low energy density. Therefore, it is crucial to thoroughly summarize recent progress in utilizing WO3 -based materials from various perspectives to enhance their performance. Herein, the potential- and pH-dependent behavior of tungsten in aqueous media is discussed. Recent progress in the advancement of nanostructured WO3 and tungsten oxide-based composites, along with related charge-storage mechanisms and their electrochemical performances in SCs and batteries, is systematically summarized. Finally, remarks are made on future research challenges and the prospect of using tungsten oxide-based materials to further upgrade energy-storage devices.

Flexible Asymmetric Solid-State Supercapacitors by Highly Efficient 3D Nanostructured α-MnO2 and h-CuS Electrodes

Abstract: A simplistic and economical chemical way has been used to prepare highly efficient nanostructured, manganese oxide (α-MnO2) and hexagonal copper sulfide (h-CuS) electrodes directly on cheap and flexible stainless steel sheets. Flexible solid-state α-MnO2/flexible stainless steel (FSS)/polyvinyl alcohol (PVA)–LiClO4/h-CuS/FSS asymmetric supercapacitor (ASC) devices have been fabricated using PVA–LiClO4 gel electrolyte. Highly active surface areas of α-MnO2 (75 m2 g–1) and h-CuS (83 m2 g–1) electrodes contribute to more electrochemical reactions at the electrode and electrolyte interface. The ASC device has a prolonged working potential of +1.8 V and accomplishes a capacitance of 109.12 F g–1 at 5 mV s–1, energy density of 18.9 Wh kg–1, and long-term electrochemical cycling with a capacity retention of 93.3% after 5000 cycles. Additionally, ASC devices were successful in glowing seven white-light-emitting diodes for more than 7 min after 30 s of charging. Outstandingly, real practical demonstration suggests...

Towards flexible solid-state supercapacitors for smart and wearable electronics

Abstract: Flexible solid-state supercapacitors (FSSCs) are frontrunners in energy storage device technology and have attracted extensive attention owing to recent significant breakthroughs in modern wearable electronics In this study, we review the state-of-the-art advancements in FSSCs to provide new insights on mechanisms, emerging electrode materials, flexible gel electrolytes and novel cell designs The review begins with a brief introduction on the fundamental understanding of charge storage mechanisms based on the structural properties of electrode materials The next sections briefly summarise the latest progress in flexible electrodes (ie, freestanding and substrate-supported, including textile, paper, metal foil/wire and polymer-based substrates) and flexible gel electrolytes (ie, aqueous, organic, ionic liquids and redox-active gels) Subsequently, a comprehensive summary of FSSC cell designs introduces some emerging electrode materials, including MXenes, metal nitrides, metal–organic frameworks (MOFs), polyoxometalates (POMs) and black phosphorus Some potential practical applications, such as the development of piezoelectric, photo-, shape-memory, self-healing, electrochromic and integrated sensor-supercapacitors are also discussed The final section highlights current challenges and future perspectives on research in this thriving field

True Meaning of Pseudocapacitors and Their Performance Metrics: Asymmetric versus Hybrid Supercapacitors

Abstract: The development of pseudocapacitive materials for energy-oriented applications has stimulated considerable interest in recent years due to their high energy-storing capacity with high power outputs. Nevertheless, the utilization of nanosized active materials in batteries leads to fast redox kinetics due to the improved surface area and short diffusion pathways, which shifts their electrochemical signatures from battery-like to the pseudocapacitive-like behavior. As a result, it becomes challenging to distinguish "pseudocapacitive" and "battery" materials. Such misconceptions have further impacted on the final device configurations. This Review is an earnest effort to clarify the confusion between the battery and pseudocapacitive materials by providing their true meanings and correct performance metrics. A method to distinguish battery-type and pseudocapacitive materials using the electrochemical signatures and quantitative kinetics analysis is outlined. Taking solid-state supercapacitors (SSCs, only polymer gel electrolytes) as an example, the distinction between asymmetric and hybrid supercapacitors is discussed. The state-of-the-art progress in the engineering of active materials is summarized, which will guide for the development of real-pseudocapacitive energy storage systems.

Recent progresses in high-energy-density all pseudocapacitive-electrode-materials-based asymmetric supercapacitors

Abstract: Recently, asymmetric supercapacitors (ASCs) have attracted extensive research interest worldwide for their potential application in emerging energy-related fields. The smart integration of high overall cell operating voltage and large capacitance can be realized in all-pseudocapacitive-electrode-materials-based ASCs. This innovative all-pseudocapacitive-asymmetric design provides a fascinating way to obtain high-energy-density devices with high power rates and also holds huge potential to bridge the gap between dielectric capacitors and rechargeable batteries. In the present review, we mainly summarized the latest contributions and progress in aqueous/non-aqueous faradaic electrode materials including conductive polymers and/or transition metal oxides/sulfides/nitrides/carbides, the operating principles, system design/engineering, and the rational optimization of all-pseudocapacitive ASCs. The intrinsic advantages and disadvantages of these unique ASCs have been elaborately discussed and comparatively evaluated. Finally, some future trends, prospects, and challenges, especially in rate capability and cycling stability, have been presented for advanced next-generation ASCs.

Environmentally-Friendly Aqueous Li (or Na)-Ion Battery with Fast Electrode Kinetics and Super-Long Life

Abstract: Environmentally-friendly aqueous Li (or Na)-ion battery with super-long life is built for large-scale energy storage. Current rechargeable batteries generally display limited cycle life and slow electrode kinetics and contain environmentally unfriendly components. Furthermore, their operation depends on the redox reactions of metal elements. We present an original battery system that depends on the redox of I−/I3− couple in liquid cathode and the reversible enolization in polyimide anode, accompanied by Li+ (or Na+) diffusion between cathode and anode through a Li+/Na+ exchange polymer membrane. There are no metal element–based redox reactions in this battery, and Li+ (or Na+) is only used for charge transfer. Moreover, the components (electrolyte/electrode) of this system are environment-friendly. Both electrodes are demonstrated to have very fast kinetics, which gives the battery a supercapacitor-like high power. It can even be cycled 50,000 times when operated within the electrochemical window of 0 to 1.6 V. Such a system might shed light on the design of high-safety and low-cost batteries for grid-scale energy storage.