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Transition metal oxides (TMOs) are recognized as high‐efficiency electrocatalyst systems for restraining the shuttle effect in lithium‐sulfur (Li−S) batteries, owing to their robust adsorption capabilities for polysulfides. However, the sluggish catalytic conversion of Li2S redox and severe passivation effect of TMOs exacerbate polysulfide shuttling and reduce the cyclability of Li−S batteries, which significantly hinders the development of TMOs electrocatalysts. Here, through the anion‐cation doping approach, dual incorporation of phosphorus and molybdenum into MnO2 (P,Mo‐MnO2) was engineered, demonstrating effective mitigation of the passivation effect and allowing for the simultaneous immobilization of polysulfides and rapid redox kinetics of Li2S. Both experimental and theoretical investigations reveal the pivotal role of dopants in fine‐tuning the d‐band center and optimizing the electronic structure of MnO2. Furthermore, this well‐designed configuration processes catalytic selectivity. Specifically, P‐doping expedites rapid Li2S nucleation kinetics by minimizing reaction‐free energy, while Mo‐doping facilitates robust Li2S dissolution kinetics by mitigating decomposition barriers. This dual‐doping approach equips P,Mo‐MnO2 with robust bi‐directional catalytic activity, effectively overcoming passivation effect and suppressing the notorious shuttle effect. Consequently, Li−S batteries incorporating P,Mo‐MnO2‐based separators demonstrate favorable performance than pristine TMOs. This design offers rational viewpoint for the development of catalytic materials with superior bi‐directional sulfur electrocatalytic in Li−S batteries. [ABSTRACT FROM AUTHOR]

Dual‐atom catalysts (DACs) have been proposed to break the limitation of single‐atom catalysts (SACs) in the synergistic activation of multiple molecules and intermediates, offering an additional degree of freedom for catalytic regulation. However, it remains a challenge to synthesize DACs with high uniformity, atomic accuracy, and satisfactory loadings. Herein, we report a facile cascade synthetic strategy for DAC via precise electrostatic interaction control and neighboring vacancy construction. We synthesized well‐defined, uniformly dispersed dual Fe sites which were connected by two nitrogen bonds (denoted as Fe‐N2‐Fe). The as‐synthesized DAC exhibited superior catalytic performances towards oxygen reduction reaction, including good half‐wave potential (0.91 V), high kinetic current density (21.66 mA cm−2), and perfect durability. Theoretical calculation revealed that the DAC structure effectively tunes the oxygen adsorption configuration and decreases the cleavage barrier, thereby improving the catalytic kinetics. The DAC‐based zinc‐air batteries exhibited impressive power densities of 169.8 and 52.18 mW cm−2 at 25 °C and −40 °C, which is 1.7 and 2.0 times higher than those based on Pt/C+Ir/C, respectively. We also demonstrated the universality of our strategy in synthesizing other M‐N2‐M DACs (M=Co, Cu, Ru, Pd, Pt, and Au), facilitating the construction of a DAC library for different catalytic applications. [ABSTRACT FROM AUTHOR]

A low water-solubility but hydrophilic coating of CaF2 is demonstrated to be effective in mitigating the susceptibility of nickel-rich cathodes to moisture and even water. The ability of the cathode to resist water erosion is not inherently linked to either hydrophobicity or hydrophilicity, but lies in robust chemical bonding within the protective layer exhibiting low water solubility. [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]

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]

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]