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The electrochemical desalination technique is recognized as a promising solution to alleviate freshwater shortages, challenges yet persists in achieving optimal energy efficiency and cost‐effectiveness. Herein, a hybrid acid/alkali zinc air desalination battery (hAA‐ZADB) capable of concurrent desalination and high‐power density is reported. To improve cathodic efficiency and cost‐effectiveness, an electrocatalyst with dual atomic Fe–Mn sites on porous dodecahedral carbon (Mn‐Fe/p‐DC) is fabricated through a simple direct pyrolysis strategy for oxygen reduction reaction (ORR). The Mn–Fe/p‐DC‐900 electrocatalyst demonstrates exceptional electrocatalytic activity (E1/2 = 0.8 V in 0.5 m H2SO4) for ORR. This innovative hybrid acid/alkali cell design, coupled with advanced electrocatalysts, empowers the hAA‐ZADB system to achieve outstanding performance benchmarks with a high open circuit voltage of 2.22 V, an impressive power density of 375 mW cm−2, and notably elevated energy output of 106.9 kJ mol−1 even at a current density of 100 mA cm−2 during desalination. Distinguishing this work is its additional functionality, evident in a rapid salt removal rate of 3.64 mg cm−2 min−1 during desalination, achieving an impressive 88.67% removal of 0.6 M NaCl. This study highlights the promising potential of employing metallic air batteries for a self‐powered desalination technique applicable to specific scenarios. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐based batteries with high energy density are highly sought after to satisfy the increasing demands on the electrochemical energy device thanks to the advantages of high safety, low cost, and fast kinetics. In this work, a high‐performance hybrid Zn–S battery (h‐ZnSB) is reported by coupling an alkali Zn anode with an acidic sulfur electrode. To this end, atomic Zn–N4 dispersed on nitrogen‐doped hollow porous carbon (Zn–NHPC) is developed as the host of sulfur that enhances efficiency due to the higher affinity of Zn–N4 to CuS than N‐doped graphene, which can reduce the vulcanization reaction barrier that is too high on N‐doped graphene. The hybrid Zn–S battery shows desired electrochemical properties, including a high open‐circuit voltage of 1.81 V, high specific capacities of 2250 mAh g−1 at 1 A g−1 and 1500 mAh g−1 at 10 A g−1, as well as a high energy density of 2372 Wh kg−1 at 10 A g−1 based on the total mass of S/C composites. The present work may provide a promising route for the development of high‐energy and high‐safety aqueous batteries. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides with high theoretical capacity usually suffer from poor intrinsic electronic conductivity and drastic volumetric change upon cycling, degrading their attractiveness for electrochemical high‐power and long‐term applications. Herein, a high‐efficiency and extensible synthetic strategy for in situ encapsulating nanostructured SnSe0.5S0.5 into N‐doped graphene (SnSe0.5S0.5 @ NG) by robust interfacial CSeSn bonds with formation of 3D porous network nanohybrids, is reported. Systematic electrochemical studies indicate that interface and structure engineering on SnSe0.5S0.5, including defects implantation, chemical bonding interaction, and nanospace confinement design, endow it with robust structural stability, ultrafast Na+ storage kinetics, and highly reversible redox reaction. In addition, the introduction of foreign Se ligand not only facilitates the transport of electrons/ions by enhancing the conductivity and decreasing the diffusion energy barrier but also generates more reactivity sites, as demonstrated by density functional theory calculations. By virtue of these superiorities, the SnSe0.5S0.5 @ NG exhibits superior sodium storage performance with high‐rate capability and long durability over 2000 cycles at 2 A g−1. Impressively, the full battery, when coupling SnSe0.5S0.5 @ NG anode with Na3V2(PO4)3/C cathode, can deliver high energy density of 213 Wh kg−1. This work provides an effective structural engineering strategy to design advanced electrode material with potential application for sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Sodium‐ion batteries (SIBs) have recently attracted increasing attention as the promising alternative to lithium‐ion batteries due to their multiple advantages of abundant reserves and low cost. However, the development of highly desirable anode materials suitable for SIBs is still hampered by a rather low capacity, poor rate capability, and cycling stability. Herein, a deliberate design to implement reliable and simple fabrication of an inverse opal structured nanohybrid of carbon‐confined various transition metal sulfides quantum dots (QDs) is presented. Comprehensive characterizations demonstrate that the hybrids hold a 3D architecture with uniform dispersion of QDs in a conductive carbon matrix that in turn encapsulates these quantum dots. With Co9S8 as an example, such a unique architecture, when applied as the anode of SIBs, endows the hybrids with multiple advantages including a high reversible specific capacity, extraordinary high rate capability, and excellent durability over 2000 cycles charging–discharging process. [ABSTRACT FROM AUTHOR]

Abstract: Perovskite solar cells have delivered power conversion efficiency beyond 22% in less than seven years, implying the potential for the paradigm shift of low‐cost photovoltaics with high efficiency and low embedded energy. Besides the “perovskite fever,” the development of new hole transport materials (HTM), especially dopant‐free HTMs, is another research hotspot. This is because the currently used HTMs, such as spiro‐OMeTAD derivatives, require additional chemical doping process to ensure sufficient conductivity and proper ionic potential level for efficient hole transport and collection. However, the commonly used dopants are volatile and hygroscopic which not only increase the complexity and cost of device fabrication but also deteriorate the device stability. So far, there have been several reviews on new HTMs, but review or analysis on dopant‐free HTMs is scarce. In this review, all reported dopant‐free HTMs are categorized into four primary different types and lessons will be learned during the separate discussions. The stability test behavior of all the intrinsic HTMs will be evaluated directly. In the end, the correlations between the properties of the intrinsic HTMs and parameters of the devices will be plotted to shed light on the future direction of development of this field. [ABSTRACT FROM AUTHOR]

A novel core‐shell‐structured hybridas an oxygen reduction reaction catalyst, consisting of nitrogen‐doped porous Fe/Fe3C@C nanoboxes supported on graphene sheets, is synthesized through simple pyrolysis of graphene oxide‐supported iron‐based metal−organic frameworks. The hybrid exhibits higher electrocatalytic activity than a commercial Pt/C catalyst, excellent long‐term stability, and superior methanol tolerance due to the synergistic effect between N‐doped Fe/Fe3C@C and N‐doped graphene sheets. [ABSTRACT FROM AUTHOR]

Potassium-Ion Hybrid Capacitors: Fast Redox Kinetics in Bi-Heteroatom Doped 3D Porous Carbon Nanosheets for High-Performance Hybrid Potassium-Ion Battery Capacitors (Adv. Keywords: fast kinetics; porous carbon nanosheets; potassium-ion hybrid capacitors; sulfur and nitrogen codoped Fast kinetics, porous carbon nanosheets, potassium-ion hybrid capacitors, sulfur and nitrogen codoped. [Extracted from the article]

Potassium‐ion hybrid capacitors (PIHCs) hold the advantages of high‐energy density of batteries and high‐power output of supercapacitors and thus present great promise for the next generation of electrochemical energy storage devices. One of the most crucial tasks for developing a high‐performance PIHCs is to explore a favorable anode material with capability to balance the kinetics mismatch between battery‐type anodes and capacitor‐type cathode. Herein, a reliable route for fabricating sulfur and nitrogen codoped 3D porous carbon nanosheets (S‐N‐PCNs) is reported. Systematic characterizations coupled with kinetics analysis indicate that the doped heteroatoms of sulfur and nitrogen and the amplified graphite interlayer can provide ample structural defects and redox active sites that are beneficial for improving pseudocapacitive activity, enabling fast kinetics toward efficient potassium‐ion storage. The S‐N‐PCNs are demonstrated to exhibit superior potassium storage capability with a high capacity of 107 mAh g−1 at 20 A g−1 and long cycle stability. The as‐developed PIHCs present impressive electrochemical performance with an operating voltage as high as 4.0 V, an energy density of 187 Wh kg−1, a power density of 5136 W kg−1, and a capacity retention of 86.4% after 3000 cycles. [ABSTRACT FROM AUTHOR]