Asymmetric supercapacitors (ASCs) have attracted significant attentions worldwide owing to their wider voltage window compared with symmetric supercapacitors (SCs). Through combinations of two electrodes with different charge storage mechanisms or different redox reactions, extended operating voltage window can be realized for ASCs. In this article, first the ASCs are classified into two types based on different charge storage mechanisms: electric double‐layer capacitive (EDLC)//pseudocapacitive‐type ASCs and EDLC//battery‐type hybrid SCs. For the EDLC/pseudocapacitive‐type ASC, carbon materials are adopted as anode and transition metal oxides including MnO2, RuO2, etc., are utilized as cathodes. For EDLC//battery‐type hybrid SCs, carbon materials as anode are combined with metal oxide/hydroxide such as NiO, and Ni(OH)2, etc., as cathode. Recently, Li‐ion‐based ASCs composed of carbon materials and Li‐ion battery‐type electrode materials with a Li‐containing organic electrolyte show great potentials to be promising alternatives. Some metal oxides/nitrides including InO2, Bi2O3, Fe3O4, Fe2O3, and VN can work in a negative potential range. By coupling another battery/pseudocapacitive electrode, all redox‐type ASCs are assembled and their electrochemical performances are widely studied. Then, based on the above categories recent advances of ASCs are summarized. Finally, the challenges and prospects for the development of ASCs are pointed out from perspectives of this study.

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Boron nitride nanosheets (BNNSs) were synthesized by the classical chemical vapor deposition (CVD) method and modified by tannic acid (TA) (named as M-BNNSs). M-BNNSs have greatly improved the thermal conductivity (0.45 W/(m·K)) and mechanical tensile strength (15.10 MPa) of epoxy resin (EP). More importantly, the EP composite coating with an appropriate amount of M-BNNS not only has an excellent anticorrosion effect (the I corr of 10%M-BNNS@EP is 8.053 × 10–7 A/cm2 after immersed in 3.5 wt % NaCl solution for 30 min) on the metal substrates but also has a good anticorrosion stability. The impedance modulus (|Z|0.01) of the 10%M-BNNS@EP coating is higher than that of the neat EP coating and other composite coating systems during 120 h of immersion. Polarization curve (Tafel) and electrochemical impedance spectroscopy (EIS) tests reveal that the 10%M-BNNS@EP coating not only has an excellent anticorrosion effect on the metal substrates but also has a good anticorrosion stability after being immersed in 3.5 wt % NaCl aqueous solution for 120 h.

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The exploration of electrocatalysts with high catalytic activity and long‐term stability for electrochemical energy conversion is significant yet remains challenging. Zeolitic imidazolate framework (ZIF)‐derived superstructures are a source of atomic‐site‐containing electrocatalysts. These atomic sites anchor the guest encapsulation and self‐assembly of aspheric polyhedral particles produced using microreactor fabrication. This review provides an overview of ZIF‐derived superstructures by highlighting some of the key structural types, such as open carbon cages, 1D superstructures, hollow structures, and the interconversion of superstructures. The fundamentals and representative structures are outlined to demonstrate the role of superstructures in the construction of materials with atomic sites, such as single‐ and dual‐atom materials. Then, the roles of ZIF‐derived single‐atom sites for the electroreduction of CO2 and electrochemical synthesis of H2O2 are discussed, and their electrochemical performance for energy conversion is outlined. Finally, the perspective on advancing single‐ and dual‐atom electrode‐based electrochemical processes with enhanced redox activity and a low‐impedance charge‐transfer pathway for cathodes is provided. The challenges associated with ZIF‐derived superstructures for electrochemical energy conversion are discussed.