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Two-dimensional (2D)/three-dimensional (3D) halide perovskite heterostructures have been extensively studied for their ability to combine the outstanding long-term stability of 2D perovskites with the superb optoelectronic properties of 3D perovskites. While current studies mostly focus on vertically stacked 2D/3D perovskite heterostructures, a theoretical understanding regarding the optoelectronic properties of 2D/3D perovskite lateral heterostructures is still lacking. Herein, we construct a series of 2D/3D perovskite lateral heterostructures to study their optoelectronic properties and interfacial charge transfer using density functional theory (DFT) calculations. We find that the band alignments of 2D/3D heterostructures can be regulated by varying the quantum-well thickness of 2D perovskites. Moreover, decreasing the 2D component ratio in 2D/3D heterostructures can be favorable to form type-I band alignment, whereas a large component ratio of 2D perovskites tends to form type-II band alignment. We can improve the amount of charge transfer at the 2D/3D perovskite interfaces and the light absorption of 2D perovskites by increasing quantum-well thickness. These present findings can provide a clear designing principle for achieving 3D/2D perovskite lateral heterostructures with tunable optoelectronic properties. [ABSTRACT FROM AUTHOR]

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]

Aqueous rechargeable zinc–iodine batteries have gained traction as a promising solution due to their suitable theoretical energy density, cost‐effectiveness, eco‐friendliness, and safety features. However, challenges such as the polyiodide shuttle effect, low iodine cathode conductivity, zinc anode dendritic growth, and the requirement for efficient separators and electrolytes hinder their commercial prospects. Hence, this review highlights recent progress in refining the core optimization strategies of zinc–iodine batteries, focusing on enhancements to the cathode, anode, separator, and electrolyte. Cathode improvements involve the addition of inorganic, organic, and hybrid materials to counteract the shuttle effect and boost redox kinetics, where these functional materials also are applied in anode modifications to curb dendritic growth and enhance cycling stability. Meanwhile, cell separator design approaches that effectively block polyiodide shuttle while promoting uniform zinc deposition are also discussed, while electrolyte innovations target zinc corrosion and polyiodide dissolution. Ultimately, the review aims to map out a strategy for developing zinc–iodine batteries that are efficient, safe, and economical, aligning with the demands of contemporary energy storage. [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]

Platinum (Pt) remains the benchmark electrocatalyst for alkaline hydrogen evolution reaction (HER), but its industry‐scale hydrogen production is severely hampered by the lack of well‐designed durable Pt‐based materials that can operate at ampere‐level current densities. Herein, based on the original oxide layer and parallel convex structure on the surface of nickel foam (NF), a 3D quasi‐parallel architecture consisting of dense Pt nanoparticles (NPs) immobilized oxygen vacancy‐rich NiOx heterojunctions (Pt/NiOx‐OV) as an alkaline HER catalyst is developed. A combined experimental and theoretical studies manifest that anchoring Pt NPs on NiOx‐OV leads to electron‐rich Pt species with altered density of states (DOS) distribution, which can efficiently optimize the d‐band center and the adsorption of reaction intermediates as well as enhance the water dissociation ability. The as‐prepared catalyst exhibits extraordinary HER performance with a low overpotential of 19.4 mV at 10 mA cm−2, a mass activity 16.3‐fold higher than that of 20% Pt/C, and a long durability of more than 100 h at 1000 mA cm−2. Furthermore, the assembled alkaline electrolyzer combined with NiFe‐layered double hydroxide requires extremely low voltage of 1.776 V to attain 1000 mA cm−2, and can operate stably for more than 400 h, which is rarely achieved. [ABSTRACT FROM AUTHOR]

Simultaneously enhancing the reaction kinetics, mass transport, and gas release during alkaline hydrogen evolution reaction (HER) is critical to minimizing the reaction polarization resistance, but remains a big challenge. Through rational design of a hierarchical multiheterogeneous three‐dimensionally (3D) ordered macroporous Mo2C‐embedded nitrogen‐doped carbon with ultrafine Ru nanoclusters anchored on its surface (OMS Mo2C/NC‐Ru), we realize both electronic and morphologic engineering of the catalyst to maximize the electrocatalysis performance. The formed Ru‐NC heterostructure shows regulative electronic states and optimized adsorption energy with the intermediate H*, and the Mo2C‐NC heterostructure accelerates the Volmer reaction due to the strong water dissociation ability as confirmed by theoretical calculations. Consequently, superior HER activity in alkaline solution with an extremely low overpotential of 15.5 mV at 10 mA cm−2 with the mass activity more than 17 times higher than that of the benchmark Pt/C, an ultrasmall Tafel slope of 22.7 mV dec−1, and excellent electrocatalytic durability were achieved, attributing to the enhanced mass transport and favorable gas release process endowed from the unique OMS Mo2C/NC‐Ru structure. By oxidizing OMS Mo2C/NC‐Ru into OMS MoO3‐RuO2 catalyst, it can also be applied as efficient oxygen evolution electrocatalyst, enabling the construction of a quasi‐symmetric electrolyzer for overall water splitting. Such a device's performance surpassed the state‐of‐the‐art Pt/C || RuO2 electrolyzer. This study provides instructive guidance for designing 3D‐ordered macroporous multicomponent catalysts for efficient catalytic applications. [ABSTRACT FROM AUTHOR]

The presolvated Li2S cathodes can be matched with lithium metal-free electrodes to overcome the safety problems of lithium–sulfur batteries, which can contribute to promising devices for next-generation energy storage fields and enhance the performance of batteries by tailoring the solid–liquid reaction interface. Most importantly, this facile loading method of liquid Li2S can provide a new opportunity to construct a commercially viable assembly for industrial batteries. However, few reviews have concentrated on the challenges and opportunities of preliquid Li2S-based batteries. Hence, we provide an overview of recent results on preliquid Li2S cathodes for high-performance batteries. First, the synthetic methods of liquid Li2S are summarized with their features. This is then followed by an up-to-date account of different functional materials to reduce the overpotential of preliquid Li2S and improve the electrochemical properties by engineering the structure, tailoring the interface, modifying catalytic sites, and adding functional materials. Finally, a short outlook is proposed about the potential future developments and commercialization processes in preliquid Li2S-based batteries. [ABSTRACT FROM AUTHOR]