| The important position of energy storage and conversion in today's human society has motivated the research of sustainable and renewable power sources to the forefront. As an alternative to batteries and traditional electrostatic capacitors, supercapacitors have attracted tremendous attention because of their good pulse charge/discharge characteristics, long life cycle (millions of cycles), and high power capabilities. These merits are essential for practical applications, rendering supercapacitors the most promising backups or auxiliary power sources for electric vehicles and electronic devices. However, even such power and energy levels of supercapacitors are still insufficient to meet emerging needs. To achieve high-performance energy-harvesting, well-defined molybdate nanowires are the prerequisite for electrode. Therefore,this research focuses on the nanocomposite and electrochemical properties and structure optimizing of supercapacitor and lithium ion battery. The core work of this paper is mainly focus on the following parts:(1) We report a facile two-step solution-based method to synthesize a nanocomposite electrode of binary MOs-conducting polymer hybrid core-shell NWs array on CC for asymmetric pseudocapacitor (ASC), where PAni is deposited onto the radically ordered NiMoO4 NWs to form NiMoO4/PAni core-shell hierarchical nanostructures by oxidative cationic polymerization. Favorable electrochemical performance has been experimentally investigated. Moreover, the ASC delivers a high specific energy and a compromise specific power. All these show excellent capacitive properties and bending dynamics.(2) In this article, we put forward a simple strategy to in-situ synthesize 1D CoMoO4 nanowires (NWs), using highly conductive CC and electrical conductive PPy wrapping layer on CoMoO4 NW arrays for high performance electrode materials. The results show that CoMoO4/PPy hybrid NWs electrode exhibits a high areal specific capacitance of ca.1.34 F cm-2 at a current density of 2 mA cm-2, which is remarkably better than the corresponding values for pure CoMoO4 NWs electrode of 0.7 F cm-2. An excellent cyclic performance of nanocomposites is achieved after 2000 cycles compared to pristine CoMoO4 NWs. An asymmetric supercapacitor composed of active carbon cathode and CoMoO4/PPy/CC anode with PVA-KOH gel served as both electrolyte and separator was also studied, in order to fulfill the synergistic effects between the two components to improve the rate capability and cycling stability of the device.(3) Based on the second experimental part, we report the hybrid core-shell NW arrays on conductive carbon cloth for lithium-ion batteries anode materials. The hybrid NWs electrode as a binder-free anode materials exhibit many merits. Primarily, CoMoO4 NW arrays directly grown on conductive CC enhance the structural integrity and electrical oneness. And also the outer conductive layer with only few nanometers thickness could increase the accessibility and accelerate the channeling of ions to the active materials.Moreover, conductive coating could effectively accommodate the volume expansion of CoMoO4 NWs during charge and discharge process. Based on these analyses, the as-synthesized CoMoO4/PPy core-shell NW arrays composites functioned as anode materials for LIBs manifested higher reversible lithium storage capacity and more excellent rate capability... |
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