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Spinel nickel cobaltite (NiCo2O4) has been proved to be one of the most promising electrode materials for high performance supercapacitors due to its high theoretic specific capacitance, excellent electronic conductivity and good environmental benignity. In this work, the unique NiCo2O4 structure was fabricated hydrothermally via the induction of the reaction temperature and investigated electrochemically as supercapacitor electrode material. The resultant NiCo2O4 electrode with hollow hierarchical microspherical structure as supercapacitor displays excellent capacitive characteristic with higher specific capacitance, better cycling stability and rate capability compared to those with various morphologies, revealing the morphology dependence of the capacitive properties of NiCo2O4 electrode owing to the discrepant electronic conductivity and ion diffusion behavior. Thus, the temperatureinduced changes in morphology are potential in the large-scale fabrication of NiCo2O4 electrode materials as supercapacitors.

A honeycomb rotary wheel fabricated from sheet adsorbent of silica gel is a competitive drying facility for air dehumidification in modern drying and air conditioning industries due to its large contacting area (3,000 m2/m3) and the rapid diffusion of the adsorbate compared to silica gel pellets. The delicate preparation procedure of hygroscopic silica gel is paramount for improved adsorption capacity by optimizing the surface area, pore size, and pore volume of silica gel. In this article, silica gel adsorbent in a honeycomb rotary wheel was fabricated by neutralizing the impregnated water glass solution with a modulus of 3.3 on the glass fiber sheet of the honeycomb matrix using CO2 at different pressure at room temperature instead of corrosive acids. The as-obtained silica gel absorbent was characterized by XRD, scanning electron microscopy (SEM), specific surface area and pore size analysis, and dynamic vapor/gas sorption analysis. The results showed that the as-obtained silica gel adsorbent is uniform in size and tunable in terms of specific surface area, pore size, pore volume, and adsorption capacity by CO2 pressure. The typical silica gel fabricated by CO2 of 0.25 MPa with a specific surface area of 764.86 m2/g, an average micropore size with a diameter of 2.94 nm, and a pore volume of 0.45 ml/g delivers a saturated adsorption capacity of as high as 287.24 mg/g at RH 50%, which is the best in adsorption performance compared to the previously reported results. This provides a new strategy for environment-friendly manufacturing of silica gel adsorbent in honeycomb rotary wheels for air dehumidification.

NiCo2S4 nanotubes were fabricated time-dependently and hydrothermally at 180 °C and investigated electrochemically as electrode materials. The results show that the as-synthesized NiCo2S4 nanotube as anode for lithium ion battery deliver an initial specific capacity of as high as 1780 mAh g -1 at the current density of 100 mA g -1 with poor cycling stability and rate capacity, indicating the potential pseudocapacitive features of NiCo2S4 nanotube. Furthermore, the NiCo2S4 nanotube electrode for supercapacitor demonstrates superior electrochemical performance with superb cycling stability and rate capability, testifying NiCo2S4 nanotube as pseudocapacitance due to the surface diffusion-controlled mechanism of charge storage. These results enable a promise of NiCo2S4 nanotube as intercalation pseudocapacitance rather than as anode for lithium ion battery.