A high-performance asymmetric supercapacitor consists of binder free electrode materials of bimetallic hydrogen phosphate (MnCo(HPO4)) hexagonal tubes and graphene ink. (10th September 2022) - Ahn, Kwang-Seon
Highlights: Novel MnCo(HPO4 ) hexagonal tubes synthesized by CBD method. Mn0.5 Co0.5 (HPO4 ) exhibit high surface area of 132 m 2 g −1 . Mn0.5 Co0.5 (HPO4 ) shows a maximum specific capacitance of 1727 F g −1 at 1 A g −1 . AAS device could withstand 95.5% of its initial capacitance after 5000 GCD cycles. Abstract: Novel bimetallic manganese-cobalt hydrogen phosphate (Mnx Cox (HPO4 )) hexagonal tubes were efficiently prepared by a direct and simple chemical bath deposition (CBD) procedure. The prepared Mnx Cox (HPO4 ) materials have been analysed through Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD) methods. The surface morphology and the particle size of the materials were studied using field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM). The textural characteristics and elemental composition of the Mnx Cox (HPO4 ) were measured using nitrogen sorption isotherms and X-ray photoelectron spectroscopy (XPS) analysis. Owing to its unique hexagonal structures and porous nature, the Mn0.5 Co0.5 (HPO4 ) electrode is measured via a three-electrode system and achieved the highest specific capacitance of 1, 727 F g −1 at the current density of 1.0 A g −1 . An aqueous asymmetric supercapacitor (AAS), Mn0.5 Co0.5 (HPO4 )//G-ink device based on Mn0.5 Co0.5 (HPO4 ) as the cathode and graphene ink (G-ink) as an anode material. The fabricated device might function well in a large operating potential window of +1.6 V. The Mn0.5 Co0.5 (HPO4 )//G-ink AAS exhibited the maximum power and specific energy of 9, 000 W kg −1 and 56.16 Wh kg −1, correspondingly at 1.0 A g −1 . Furthermore, the fabricated device could withstand 95.5% of its primary capacitance after 5, 000 galvanostatic charge/discharge (GCD) turns, which illustrates that the materials could be a prominent contender for supercapacitor applications. Graphical abstract: Image, graphical abstract