Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems. Metal–organic frameworks (MOFs), as a new type of porous material, show the advantages of large specific surface area, high porosity, low density, and adjustable pore size, exhibiting a broad application prospect in the field of electrocatalytic reactions, batteries, particularly in the field of supercapacitors. This comprehensive review outlines the recent progress in synthetic methods and electrochemical performances of MOF materials, as well as their applications in supercapacitors. Additionally, the superiorities of MOFs-related materials are highlighted, while major challenges or opportunities for future research on them for electrochemical supercapacitors have been discussed and displayed, along with extensive experimental experiences.

No abstract

Transition metal selenides anodes with fast reaction kinetics and high theoretical specific capacity are expected to solve mismatched kinetics between cathode and anode in Li‐ion capacitors. However, transition metal selenides face great challenges in the dissolution and shuttle problem of lithium selenides, which is the same as Li‐Se batteries. Herein, inspired by the density functional theory calculations, heterogeneous can enhance the adsorption of Li2Se relative to single component selenide electrodes, thus inhibiting the dissolution and shuttle effect of Li2Se. A heterostructure material (denoted as CoSe2/SnSe) with the ability to evolve continuously (CoSe2/SnSe→Co/Sn→Co/Li13Sn5) is successfully designed by employing CoSnO3‐MOF as a precursor. Impressively, CoSe2/SnSe heterostructure material delivers the ultrahigh reversible specific capacity of 510 mAh g−1 after 1000 cycles at the high current density of 4 A g−1. In situ XRD reveals the continuous evolution of the interface based on the transformation and alloying reactions during the charging and discharging process. Visualizations of in situ disassembly experiments demonstrate that the continuously evolving interface inhibits the shuttle of Li2Se. This research proposes an innovative approach to inhibit the dissolution and shuttling of discharge intermediates (Li2Se) of metal selenides, which is expected to be applied to metal sulfides or Li‐Se and Li‐S energy storage systems.

Metal–organic frameworks (MOFs) have been widely adopted in various fields (catalysis, sensor, energy storage, etc.) during the last decade owing to the trait of abundant surface chemistry, porous structure, easy‐to‐adjust pore size, and diverse functional groups. However, the limited active sites and the poor conductivity hinder the relative practical application. 2D MOFs can shorten the ion transport path with the merit of layered structure. The large surface area can increase the number of active sites as well as effectively utilize the sufficient active sites, exhibiting enormous potential in the field of energy storage systems (EESs). In this review, the characteristics of the 2D MOFs have been introduced, and the systematic synthesis methods (top‐down and bottom‐up) of 2D MOFs are presented, providing fundamental understanding for the construction of 2D MOFs. Moreover, the applications of 2D MOFs in energy storage fields such as supercapacitors and batteries are demonstrated in detail. Finally, the future development prospects have been proposed, offering guidelines for the rational utilization of 2D MOFs and promoting the understanding of 2D MOFs in EESs.

Aqueous zinc anode has been re-evaluated due to the superiority in tackling safety and cost concerns. However, the limited lifespan originating from Zn dendritic and side reactions largely hamper commercial development. Currently, the coating prepared by simple slurry mixing is leaky and ineffectively isolate sulfate and water. Herein, inspired by the DFT calculations and the easy hydrolysis characteristic of MIL-125 (Ti), an in-situ grown high-dense TiO 2-x solid electrolyte interphase (HDSEI) with rich oxygen vacancies is successfully constructed in an aqueous electrolyte, in which the oxygen vacancies not only strengthen the hydrogen binding force thereby inhibiting the hydrogen precipitation by-reaction, but also reduce the migration energy barrier of zinc ions and enhance the mechanical properties. Profiting from the HDSEI, symmetric Zn cells survive up to remarkable 4200 h at 1 mA cm −2 , nearly 42-times than that of bare Zn anodes. In situ optical microscopy clearly reveals that the in situ grown HDSEI homogenizes the zinc deposition process, while bare zinc without HDSEI shows significant dendrites, confirming the protective nature of HDSEI. Furthermore, full Zn ion capacitors can deliver excellent electrochemical performance, providing a feasible in situ approach to construct HDSEI to implement dendrite-free metal anodes.