Ammonia-Assisted Growth of CoSn(OH)6 Nanostructures and Their Electrochemical Performances for Supercapacitor.

In this work, ammonia-assisted one step growth of SnO2 and mixed metal hydroxide CoSn(OH)6 on Ni foam is illustrated. The nanostructured films grown on Ni foam are highly porous in nature. The CoSn(OH)6 nanostructures were deposited using three different molar ratios of Sn/Co precursors i.e., 1:1, 1:2 and 2:1 and their performances as supercapacitor have been investigated and compared with pristine SnO2. Interestingly, the CoSn(OH)6 thin films prepared with 1:2 molar ratio of Sn/Co showed remarkably high areal capacitance and good cyclic stability. It is believed that the presence of different metal cations and their valence states along with the porous nanostructure makes the material outstanding as supercapacitor. The highest areal capacitance of 4189 mF cm-2 was obtained at a current density of 2 mA cm-2 for CoSn(OH)6 thin films offering an excellent cyclic stability with a capacity retention of 90.3% after 2000 cycles.

Deposition of Tin Oxide Thin Films by Successive Ionic Layer Adsorption Reaction Method and Its Characterization.

Tin oxide thin films were uniformly deposited by successive ionic layer adsorption reaction (SILAR) method on glass substrates using ethylene diamine as a complexing agent. The proper annealing treatment in air converts as-deposited amorphous films into crystalline and removes defects, reducing strain in the crystal lattice. The films were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Atomic Force Microscopy (AFM), Fourier Transform Infrared (FTIR) spectroscopy. The film shows good optical transparency in the range of 200-1000 nm wavelength and electrical resistivity decreases upon annealing.

Facile synthesis of flower-like morphology Cu0.27Co2.73O4 for a high-performance supercapattery with extraordinary cycling stability.

The partial replacement of Co by Cu in cobaltite to give Cu0.27Co2.73O4 with unique flower-like morphology is found to be very beneficial for supercapacitor-battery hybrid applications. The 3D architecture of the material on a conductive substrate resulted in outstanding supercapattery performance. Asymmetric assembly of the material with activated carbon in a two-electrode system delivered high energy and power densities as well as a high specific capacity. The device also showed excellent cycling stability over 20 000 cycles, with a capacity retention value of 86.9%.