Synthesis and Printing Features of a Hierarchical Nanocomposite Based on Nickel–Cobalt LDH and Carbonate Hydroxide Hydrate as a Supercapacitor Electrode

Abstract

The hydrothermal synthesis of a hierarchically organized nanocomposite based on nickel–cobalt carbonate hydroxide hydrate of composition M(CO3)0.5(OH)·0.11H2O (where M is Ni2+ and Co2+) and nickel–cobalt layered double hydroxides (NiCo-LDH) was studied. Using synchronous thermal analysis (TGA/DSC), it was determined that the material retained thermal stability up to 200 °C. The crystal structure of the powder and the set of functional groups in its composition were determined by X-ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FTIR). The resulting hierarchically organized nanopowder was employed as a functional ink component for microplotter printing of an electrode film, which is an array of miniature planar structures with a diameter of about 140 μm, on the surface of a nickel-plated steel substrate. Using scanning electron microscopy (SEM), it was established that the main area of the electrode “pixels” represents a thin film of individual nanorods with periodic inclusions of larger hierarchically organized spherical formations. According to atomic force microscopy (AFM) data, the mean square roughness of the material surface was 28 nm. The electrochemical properties of the printed composite film were examined; in particular, the areal specific capacitance at different current densities was calculated, and the electrochemical kinetics of the material was studied by impedance spectroscopy. It was found that the electrode material under study exhibited relatively low Rs and Rct resistance, which indicates active ion transfer at the electrode/electrolyte interface.

Multioxide combinatorial libraries: fusing synthetic approaches and additive technologies for highly orthogonal electronic noses

“…The hydrothermal method was used to synthesize nanomaterials with compositions of (CeO 2 ) 0.8 (Sm 2 O 3 ) 0.2 , NiCo 2 O 4 , and NiO #5. 50,84 The synthesis was carried out by hydrothermal treatment of solutions of inorganic salts of the corresponding metals in the presence of urea at 120, 160, and 180 °C for (CeO 2 ) 0.8 (Sm 2 O 3 ) 0.2 , NiCo 2 O 4 , and NiO #5, respectively, followed by heat treatment of the resultant intermediates. Oxide powders of V 2 O 5 –WO 3 , where the WO 3 content varied in the range of 0–50 mol%, In 2 O 3 –SnO 2 (43 mol% SnO 2 ), and NiO composition #2–4, were produced using a combination of sol–gel method or chemical precipitation followed by hydrothermal treatment of the resultant particles.…”

“…Subsequently, the resulting ink was applied to the surface of the chip by microplotter printing. 61,84 The materials were plotted using a capillary dispenser in the form of a hollow glass needle with a capillary diameter of about 100 μm. The resulting meniscus touched the surface of the chip in the gap between the platinum strip electrodes.…”

Current Trends and Promising Electrode Materials in Micro-Supercapacitor Printing

“…Layered double hydroxides (LDH), which have much higher electrical conductivity compared to individual hydroxides, attract the most attention. A very popular representative of LDHs is nickel-cobalt hydroxide (NiCo-LDH), which is actively used in the fabrication of electrodes of miniature supercapacitors, including printed technologies [ 138 ] ( Figure 6 ). In [ 139 ], the formation of an electrode based on the above material on the surface of nickel foam was carried out by the authors using inkjet printing.…”