Sachin S. Pujari

Bio: Sachin S. Pujari is an academic researcher. The author has contributed to research in topics: Thin film & Supercapacitor. The author has an hindex of 5, co-authored 9 publications receiving 62 citations.

Enhanced Energy Density of All-Solid-State Asymmetric Supercapacitors Based on Morphologically Tuned Hydrous Cobalt Phosphate Electrode as Cathode Material

Abstract: In the present investigation, microflowers-like hydrous cobalt phosphate is prepared via a facile single-step hydrothermal method on stainless steel substrate. The microflowers-like morphology of hydrous cobalt phosphate thin film consists of microplates and further microplates converted to flakes by means of a change in length, width, and thickness with urea variation. Hydrous cobalt phosphate thin film electrode demonstrates a high specific capacitance of 800 F g–1 at 2 mA cm–2 with 33.62 Wh kg–1 energy density and 3.12 kW kg–1 power density. By taking advantage of hydrous cobalt phosphate thin film (as a cathode electrode) and copper sulfide thin film (as an anode electrode), the asymmetric devices (aqueous/all-solid-state) are fabricated. Aqueous asymmetric device shows a high specific capacitance of 163 F g–1 at 2 mA cm–2 with an energy density of 58.12 Wh kg–1 and power density of 3.52 kW kg–1. Moreover, the all-solid-state asymmetric supercapacitor device delivers a high specific capacitance of 70 ...

Facile Synthesis of Microstrip-Like Copper Phosphate Hydroxide Thin Films for Supercapacitor Applications

Abstract: Binder-free copper phosphate hydroxide [Cu2(PO4)(OH)] thin films have been prepared on stainless-steel (SS) substrates at 393 K via a facile hydrothermal method. X-ray diffraction analysis confirmed the formation of orthorhombic-structured copper phosphate hydroxide [Cu2(PO4)(OH)] thin films with uniform microstrip-like morphology and Brunauer–Emmett–Teller (BET) surface area of 5.26 m2 g−1. The electrochemical performance of the films depended on their thickness, with a maximum specific capacitance of 280 F g−1 at a scan rate 5 mV s−1 in 1 M KOH electrolyte. The [Cu2(PO4)(OH)] electrode delivered an energy density of 3.85 Wh kg−1 and a power density of 264.70 W kg−1 with excellent (91%) capacitive retention after 2000 cycles. This excellent electrochemical performance shows that such microstrip-like Cu2(PO4)(OH) thin films are promising electrodes for high-performance supercapacitors.

Chemical supercapacitors: a review focusing on metallic compounds and conducting polymers

Abstract: Capacitors began their journey in 1745, and to date have advanced in the form of supercapacitors. Supercapacitors are one of the advanced forms of capacitors with higher energy density, bridging capacitors and batteries. The energy storage through the formation of an electrical double layer is pivotal for supercapacitor technology. Accordingly, to further improve the energy density, surface faradaic (pseudocapacitive) processes are employed, and henceforth, the journey of chemical supercapacitors commenced. Herein, the materials, mechanisms and fabrication of chemical supercapacitors based on metallic compounds and conducting polymers are discussed in detail. The inherent limitations of these materials are addressed, and the feasible mitigation measures are identified. Poor conductivity, slow diffusion kinetics and rapid structural disintegration over cycling are the common constraints of metallic compounds, which can be overcome by preparing conductive nanocomposites. Thus, versatile conductive nanocomposites of metal oxides, hydroxides, carbides, nitrides, phosphides, phosphates, phosphites, and chalcogenides are elaborated. A lack of structural integrity is the prime obstacle for the realization of conducting polymer-based supercapacitors, which may be solved by forming composites with robust support from carbonaceous materials or metallic compounds. Consequently, the composites of polyaniline, polypyrrole, polythiophene and polythiophene-derivatives are discussed. The historical accounts of early stages of works are emphasised in order to review the developmental pathways of chemical supercapacitors. The construction of full cells and their performance data are presented herein, which synchronize the behaviour of practical scaled-up devices. To the best of our knowledge, this review is the first holistic description of chemical supercapacitors based on metallic compounds and conducting polymers from the first reports to recent advancements.