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The high performance of aqueous zinc–iodine batteries is limited by the soluble polyiodide shuttling and sluggish redox kinetics. Various strategies have been proposed to address these issues, but most of these optimizing strategies either add additional hurdles to the manufacturing process or require materials that are not currently commercially available. Herein, we take advantage of commercial 1,2-dimethyl-3-propylimidazolium iodide to serve as a redox reaction catalyst for the activation of iodine cathodes without any other material modification. Due to the strong bonding coordination between 1,2-dimethyl-3-propylimidazolium iodide and the polyiodides, the as-prepared cell has a high specific capacity (147 mA h g−1) at 50C, and ultralong cycling performance (20 000 cycles) with better capacity retention. This work introduces an effective and commercial material that enables bringing aqueous rechargeable zinc iodine batteries to the practical energy market. [ABSTRACT FROM AUTHOR]

Binary organic solar cells (OSCs) having a controllable phase‐separated morphology of active layers and simple solution manufacturing are desirable for organic photovoltaic adaptation. However, low hole mobility and an unbalanced hole‐ and electron transport reduce the power conversion efficiency (PCE) of the OSCs. Here, a highly efficient binary OSC with a poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS) buffer layer as a hole transport layer (HTL) via using a water‐soluble sulfonate to wrap the PEDOT:PSS core‐shell structures in solutions is reported. The PEDOT1:PSS2.80 buffer layers have good merits including i) a smooth, homogeneous, and hydrophilic surface for an intimate contact, ii) a high work function and raised surface potentials with much uniform distributions for an energy band alignment, and iii) a high optical transmittance in the broad spectral region from 400 to 1100 nm along with an improved electrical conductivity. Benefiting from a raised hole mobility and a better charge‐mobility balance, the solution‐processed binary OSCs yielded a high PCE of 18.62%. 18.62% is one of the highest values among these binary OSCs based on the PEDOT:PSS HTLs and PM6:L8‐BO active layers. The PEDOT1:PSS2.80 buffer layers are superior to the pristine PEDOT1:PSS2.60 buffer layers in terms of raising the OSC efficiency. [ABSTRACT FROM AUTHOR]

Heterogeneous structures and doping strategies have been intensively used to manipulate the catalytic conversion of polysulfides to enhance reaction kinetics and suppress the shuttle effect in lithium‐sulfur (Li‐S) batteries. However, understanding how to select suitable strategies for engineering the electronic structure of polar catalysts is lacking. Here, a comparative investigation between heterogeneous structures and doping strategies is conducted to assess their impact on the modulation of the electronic structures and their effectiveness in catalyzing the conversion of polysulfides. These findings reveal that Co0.125Zn0.875Se, with metal‐cation dopants, exhibits superior performance compared to CoSe2/ZnSe heterogeneous structures. The incorporation of low Co2+ dopants induces the subtle lattice strain in Co0.125Zn0.875Se, resulting in the increased exposure of active sites. As a result, Co0.125Zn0.875Se demonstrates enhanced electron accumulation on surface Se sites, improved charge carrier mobility, and optimized both p‐band and d‐band centers. The Li‐S cells employing Co0.125Zn0.875Se catalyst demonstrate significantly improved capacity (1261.3 mAh g−1 at 0.5 C) and cycle stability (0.048% capacity delay rate within 1000 cycles at 2 C). This study provides valuable guidance for the modulation of the electronic structure of typical polar catalysts, serving as a design directive to tailor the catalytic activity of advanced Li‐S catalysts. [ABSTRACT FROM AUTHOR]

Potassium‐ion batteries (PIBs) have attracted increasing interest as promising alternatives to lithium‐ion batteries (LIBs) in large‐scale electrical energy storage systems due to the potential price advantages, abundant availability of potassium resources, and low standard redox potential of potassium. However, the pursuit of suitable cathode materials that exhibit desirable characteristics such as voltage platforms, high capacity, and long cycling stability is of utmost importance. Recently, layered transition‐metal oxides for PIBs offer great potential due to their high theoretical capacity, suitable voltage range, and eco‐friendliness. Nevertheless, the progress of KxMO2 cathodes in PIBs faces obstacles due to the detrimental effects of structural disorder and irreversible phase transitions caused by the Jahn‐Teller effect. This review provides a brief description of the origin and mechanism of the Jahn‐Teller effect, accompanied by the proposed principles to mitigate this phenomenon. In particular, the current status of KxMO2 cathodes for PIBs, is summarized highlighting the challenges posed by the Jahn‐Teller effect. Furthermore, promising strategies, such as composition modulation, synthesis approaches, and surface modification, are proposed to alleviate and suppress the Jahn‐Teller effect. These strategies offer valuable insights into the prospects of innovative cathode materials and provide a foundation for future research in the field of PIBs. [ABSTRACT FROM AUTHOR]