Technical development in electronic devices is frequently stifled by their insufficient capacity and cyclic stability of energy-storage devices. The nano-structured materials have sensational importance for providing novel and optimized combination to overcome exiting boundaries and provide efficient energy storage systems. Metal hydroxide materials with high capacity for pseudo-capacitance properties have grabbed special attention. Lately, the blend of nickel and cobalt hydroxides has been considered as a favorable class of metallic hydroxide materials owing to their comparatively high capacitance and exceptional redox reversibility. The sulfonated carbon nanotube fluid (SCNTF) was prepared by the ion exchange method to be utilized as the exceptional templates due to astonishing specific surface area, ensuring the maximum utilization of the active material. The CoNi-layered double hydroxides (LDHs)/SCNTF core-shell nanocomposite was prepared by the simple solvothermal method. Structural analysis showed that the composite material had the high conductance of carbon materials, the pseudo-capacitance characteristics of metal hydroxides, and porous structure, which facilitates the ion shuttle when the electrolyte reacts with the active material. Electrochemical analysis results showed that CoNi-LDHs/SCNTF had excellent rate performance, reversible charge-discharge properties and cycle stability. It exhibited an extreme specific capacity of 1190.5 F g?1 at a current density of 1 A g?1; whereas specific capacity remained 953.7 F g?1 at the current density was 10 A g?1. In addition, the capacity retention rate after 5000 charge-discharge cycles at a current density of 20 A g?1 was 81.0%. The results indicated that the CoNi-LDHs/SCNTF core-shell nanocomposite material is cost efficient and an effective substitute in energy storage applications. 相似文献
With rapid socioeconomic and population growth, high-quality arable land resources are decreasing daily, especially in arid areas, which makes arable land reserve resources an important way to supplement arable land. How to accurately evaluate cultivated land reserve resources is of great significance to socioeconomic development and sustainable land use in arid areas. Therefore, this study selected Hangjin Banner as a typical area and calculated the regional maximum available irrigation water based on the principle of regional water balance. Then, the "irrigation area check algorithm" was used to evaluate the amount of cultivated land reserve resources, and policy recommendations were proposed for the development and utilization of cultivated land resources. The results showed that Hangjin Banner had no cultivated land reserve resources under the current irrigation method and had cultivated land reserve resources under the efficient water-saving irrigation method, but only in the southern zone during normal and partially abundant water years. Therefore, we believe that arid areas should adhere to the "set land by water" principle, the allocation of water resources should be optimized, and cultivated land resources with high quality should be utilized based on the actual regional conditions.