Heterogeneous nanostructure array for electrochemical energy conversion and storage

Abstract

Rapid development of modern society raises more and more requirements for highly efficient energy conversion and storage. Electrochemical devices stand out as a most viable option for eventual substitute for fossil fuels, but suffer from problems like durability, operability, etc. Heterogeneous nanostructure arrays with distinguished superiorities have thus attracted intensive attention and yielded favorable electrochemical performance. In pursuit of deep understandings of their working modes, this review will focus on the interconnection among different constituents within each individual unit to correlate microscopic electrochemical processes with macroscopic performance. Here, the motivation of employing heterogeneous nanostructure arrays is first summarized. Then, the design principles, including three working modes, 'Function-Function', 'Function-Assistance', 'Single-unit device', are analyzed comprehensively to illuminate the interconnection among different constituents in electrochemical energy conversion and storage processes. Solar water splitting (energy conversion), alkali-ion battery and supercapacitors (energy storage) are termed collectively as typical electrochemical energy technologies to illustrate the

Well‐Defined Nanostructures for Electrochemical Energy Conversion and Storage

“…The first solution is to combine different distinct nano‐units to form hetero‐architectures (Figure 1d), such as core/shell, sandwich, multi‐segment structures. [ 11 ] Note that, each nano‐unit of the hetero‐architectures could be adjusted independently to complement with other units so that the combined nano‐units can work together to achieve new effects and benefits that might be inaccessible by their single counterparts. Moreover, for almost all applications of nanostructures in energy conversion and storage, millions of nanostructures shall be integrated or patterned into a large‐scale macroscopic area so as to be used as the electrode of a functional device.…”

Hierarchical N-Doped Porous Carbons for Zn–Air Batteries and Supercapacitors

“…However, the movement toward a greener economy requires energy storage. Electrochemical energy devices, such as fuel cells, metal–air batteries, and supercapacitors, are expected to play a crucial role in the transition to a sustainable future [ 1 ]. The oxygen reduction reaction (ORR) is an important cathodic reaction in fuel cells and metal–air batteries.…”

Integrated Nanostructural Electrodes Based on Layered Double Hydroxides

“…Two‐dimensional (2D) nanomaterials with sheet‐like structures, including graphene, transition metal dichalcogenides (TMDs), layered double hydroxides (LDHs), MXenes, metal–organic frameworks (MOFs), and covalent‐organic frameworks (COFs), have sparked increasing interest in energy‐related fields owing to their versatile desired properties. The double‐sided surface structure not only increased the specific surface area but also generated abundant exposed active sites, which are key roles for the electrochemical reaction .…”

“…[13] Thus, the development of promising materials with suitable physical and chemical properties (e.g., large specific surface area, rich porous structure, superior surface functionality, excellent electric conductivity and stability) is highly required for future energy storage and conversion. [14,15] Two-dimensional (2D) nanomaterials with sheet-like structures, including graphene, [16] transition metal dichalcogenides (TMDs), [17,18] layered double hydroxides (LDHs), [19] MXenes, [20] metal-organic frameworks (MOFs), [21] and covalent-organic frameworks (COFs), [22] have sparked increasing interest in energyrelated fields owing to their versatile desired properties. The double-sided surface structure not only increased the specific surface area but also generated abundant exposed active sites, which are key roles for the electrochemical reaction.…”