Nanowires in Energy Storage Devices: Structures, Synthesis, and Applications

Abstract

great significance in solving the current energy crisis and environmental problems in human society. [1] Solar energy, wind energy, hydropower, and nuclear power are used as environmentally friendly and sustainable energy sources. [2] However, the seasonal characteristic, regionalism, and discontinuity make it hard to use the clean energy directly in the industries and daily life. Therefore, how to store these energy sources is a hot spot of concern. Currently, different kinds of energy storage technologies for stationary applications include mechanical, chemical, electrical, and electrochemical energy storage. [3,4] Among them, the electrochemical energy storage has higher efficiency, longer cycle life, lower cost, sustainability, and other favorable features, which has shown great prospects. Recently, lithium-ion batteries have become the mainstream of electrochemical energy storage devices, and have played an important role in smart grids, electric vehicles, and personal electronic devices. [5] However, people are still finding better alternatives, due to the scarcity of lithium resources, high prices, and safety issues. [6,7] Researches on sodium-ion batteries, [8,9] potassiumion batteries, [10] and multivalent batteries [11] are also underway. It is hard to get ideal electrochemical energy storage devices with high power and energy density at the same time. Trying to balance the indexes, researches on the battery-supercapacitor hybrid devices have also been studied. [12] The two electrodes are the capacitive electrode and the battery-type electrode. The energy density would be improved through capacity improvement and voltage expansion.In order to accomplish the goals above, scientists have attempted to use sundry forms of nanomaterials to improve electrochemical performance. [13] 1D nanomaterials (nanowires (NWs)/nanorods/nanotubes/nanofibers) have attracted a wide range of interests due to their unique functional characteristics. Nanowire is one of these structures that possess several practical properties, such as crystallinity, well-controlled dimensional composition, and electronic radial transport, which helps to manufacture the nanoscale systems and useful devices in electrochemical energy storage. After several decades, the application potential of nanowires in energy storage has been explored, and their advantages can partially be adapted to expectations of people on electrode materials. [14] The advantages of Accompanied by the development and utilization of renewable energy sources, efficient energy storage has become a key topic. Electrochemical energy storage devices are considered to be one of the most practical energy storage devices capable of converting and storing electrical energy generated by renewable resources, which are also used as the power source of electric vehicles and portable electronic devices. The ultimate goals of electrochemical energy storage devices are long lifespan, high safety, high power, and high energy density. To achieve the above goals, researchers have attempted t...

Importance of Electrocatalyst Morphology for the Oxygen Reduction Reaction

“…These materials have been utilized in the field of electrocatalysis and energy conversion. [65][66][67] As for electrocatalysts of the ORR, 1D MÀ NÀ C materials have also attracted great attention. [68] The morphologies of reported 1D MÀ NÀ C materials include nanofibers, nanowires, nanorods, and nanotubes.…”

Large‐Area, Uniform, Aligned Arrays of Na3(VO)2(PO4)2F on Carbon Nanofiber for Quasi‐Solid‐State Sodium‐Ion Hybrid Capacitors

“…In this work, we use a one‐step hydrothermal process to grow large‐area, uniform and well‐aligned NVPF arrays on a flexible freestanding carbon nanofiber membrane. As compared to other carbon substrates, 1D carbon nanofiber architecture could form efficient current pathways, shorten the ion diffusion length and provide high surface area, increasing large electrolyte–electrode contact area . The growth process of NVPF can be controlled by changing the reaction time.…”

“…As compared to other carbon substrates, 1D carbon nanofiber architecture could form efficient current pathways, shorten the ion diffusion length and provide high surface area, increasing large electrolyte-electrode contact area. [45,46] The growth process of NVPF can be controlled by changing the reaction time. This electrode design has the unique merits during the Na + extraction/ insertion process.…”

Hybrid Supercapacitors Based on Interwoven CoO‐NiO‐ZnO Nanowires and Porous Graphene Hydrogel Electrodes with Safe Aqueous Electrolyte for High Supercapacitance

“…A series of different ternary metal oxide electrode materials were produced such as Ni-Co-Fe, Ni-Co-Al, and Ni-Co-Cu. [31] It has been reported that the presence of an appropriate amount of oxygen vacancies can greatly increase the specific capacitance of NiO and ZnO, [32,33] which may result from the increase of ion conduction velocity caused by surface defects. Then, morphology has a great influence on electrochemical properties of the material.…”