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The significance of exploring optimal electrode materials cannot be overstated, particularly in mitigating the critical issues posed by sluggish redox kinetics, significant volume variations, and severe structural collapse resulting from the insertion and extraction of sodium ions. These efforts are crucial for enhancing the longevity and rapid charging capabilities of sodium‐ion batteries (SIBs). Herein, a defect engineering strategy for the in situ encapsulation of single‐phase ternary iron phosphoselenide into porous carbon by robust chemical bonds with the formation of rod‐like multicavity nanohybrids (FePSe3@C) is presented. The incorporation of Se atom not only modulates the electronic structure of the central metal Fe atom and enhances the intrinsic electrical conductivity, but also generates numerous additional reaction sites and accelerates the reaction kinetics of FePSe3@C, as corroborated by theoretical calculations and kinetic analysis. Notably, the FePSe3@C demonstrates an outstanding rate capability of 321.7 mAh g−1 even at 20 A g−1 and long cycling stability over 1000 cycles. The sodium‐ion full cell, pairing the FePSe3@C anode with the Na3V2(PO4)3@C cathode, exhibits a remarkable energy density of 202 Wh kg−1, demonstrating its practical applicability. This work provides a controllable defect and morphology engineering strategy to construct advanced materials with fast charge transfer for high‐power/energy SIBs. [ABSTRACT FROM AUTHOR]

In both the manufacturing and chemical industries, benzoquinone is a crucial chemical product. A perfect and economical method for making benzoquinone is the electrochemical oxidation of phenol, thanks to the traditional thermal catalytic oxidation of phenol process requires high cost, serious pollution and harsh reaction conditions. Here, a unique heterostructure electrocatalyst on nickel foam (NF) consisting of nickel sulfide and nickel oxide (Ni9S8‐Ni15O16/NF) was produced, and this catalyst exhibited a low overpotential (1.35 V vs. RHE) and prominent selectivity (99 %) for electrochemical phenol oxidation reaction (EOP). Ni9S8‐Ni15O16/NF is beneficial for lowering the reaction energy barrier and boosting reactivity in the EOP process according to density functional theory (DFT) calculations. Additionally, an alkali/acid hybrid flow cell was successfully established by connecting Ni9S8‐Ni15O16/NF and commercial RuIr/Ti in series to catalyze phenol oxidation in an alkaline medium and hydrogen evolution in an acid medium, respectively. A cell voltage of only 0.60 V was applied to produce a current density of 10 mA cm−2. Meanwhile, the system continued to operate at 0.90 V for 12 days, showing remarkable long‐term stability. The unique configuration of the acid‐base hybrid flow cell electrolyzer provides valuable guidance for the efficient and environmentally friendly electrooxidation of phenol to benzoquinone. [ABSTRACT FROM AUTHOR]

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]

Rechargeable Zn–air batteries (ZABs) are considered highly competitive technologies for meeting the energy demands of the next generation, whether for energy storage or portable power. However, their practical application is hindered by critical challenges such as low voltage, CO2 poisoning at the cathode, low power density, and poor charging efficiency Herein, a rechargeable hybrid alkali/acid Zn–air battery (h‐RZAB) that effectively separates the discharge process in an acidic environment from the charging process in an alkaline environment, utilizing oxygen reduction reaction (ORR) and glycerol oxidation reaction (GOR) respectively is reported. Compared to previously reported ZABs, this proof‐of‐concept device demonstrates impressive performance, exhibiting a high power density of 562.7 mW cm−2 and a high operating voltage during discharging. Moreover, the battery requires a significantly reduced charging voltage due to the concurrent utilization of biomass‐derived glycerol, resulting in practical and cost‐effective advantages. The decoupled system offers great flexibility for intermittently generated renewable power sources and presents cost advantages over traditional ZABs. As a result, this technology holds significant promise in opening avenues for the future development of renewable energy‐compatible electrochemical devices. [ABSTRACT FROM AUTHOR]

Aqueous zinc (Zn) based batteries show great promise as energy storage devices, cost‐effectiveness, and intrinsic safety. However, the development of Zn‐based batteries faces significant challenges, primarily stemming from poor electrochemical reversibility caused by dendrite growth, hydrogen generation, and byproduct formation on the Zn anode. In this study, valine (Val) is investigated as an electrolyte additive to finely tune the interface microenvironment, resulting in enhanced electrochemical stability of the Zn anode across a wide pH range, marking the first time such an approach has been explored. Val ions preferably adsorb onto the active sites of the Zn anode surface, enabling efficient isolation of water and SO42− from the desolvated shell layer and thus effectively inhibiting dendrite growth. The Zn||Zn symmetric cells are demonstrated with Val electrolyte additives present a remarkable cycling performance of 5400 h. Furthermore, Zn||MnO2 full cells exhibit stable operation for 5000 cycles at 3 A g−1. Notably, the Val additive also functions effectively in rechargeable alkaline cells, enabling the alkaline symmetric cells and Zn||Ni0.8Co0.1Mn0.1O2 full cells to operate durably across a wide temperature range. This work offers unique insights into electrolyte engineering for aqueous rechargeable batteries, especially in terms of their compatibility with a wide pH range. [ABSTRACT FROM AUTHOR]

Alloying‐type antimony (Sb) with high theoretical capacity is a promising anode candidate for both lithium‐ion batteries (LIBs) and sodium‐ion batteries (SIBs). Given the larger radius of Na+ (1.02 Å) than Li+ (0.76 Å), it was generally believed that the Sb anode would experience even worse capacity degradation in SIBs due to more substantial volumetric variations during cycling when compared to LIBs. However, the Sb anode in SIBs unexpectedly exhibited both better electrochemical and structural stability than in LIBs, and the mechanistic reasons that underlie this performance discrepancy remain undiscovered. Here, using substantial in situ transmission electron microscopy, X‐ray diffraction, and Raman techniques complemented by theoretical simulations, we explicitly reveal that compared to the lithiation/delithiation process, sodiation/desodiation process of Sb anode displays a previously unexplored two‐stage alloying/dealloying mechanism with polycrystalline and amorphous phases as the intermediates featuring improved resilience to mechanical damage, contributing to superior cycling stability in SIBs. Additionally, the better mechanical properties and weaker atomic interaction of Na−Sb alloys than Li−Sb alloys favor enabling mitigated mechanical stress, accounting for enhanced structural stability as unveiled by theoretical simulations. Our finding delineates the mechanistic origins of enhanced cycling stability of Sb anode in SIBs with potential implications for other large‐volume‐change electrode materials. [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH4) has earned recognition as a promising hydrogen carrier, attributed to its exceptional hydrogen storage capacity, boasting a high theoretical storage capacity of 10.8 wt %. Nonetheless, the utilization of traditional pyrolysis and hydrolysis methods still presents a formidable challenge in achieving controlled hydrogen generation especially under ambient conditions. In this work, we report an innovative electrochemical strategy for production H2 by coupling NaBH4 electrooxidation reaction (BOR) at anode in alkaline media with hydrogen evolution reaction (HER) at cathode in acidic media. To implement this, we have developed a bifunctional electrocatalyst denoted as Pd‐Mo2C@CNTs, wherein Pd nanoparticles are grown in situ on Mo2C embedded within N‐doped carbon nanotubes. This electrocatalyst demonstrates exceptional performance in catalyzing both alkaline BOR and acidic HER. We have developed a hybrid acid/alkali cell, utilizing Pd/Mo2C@CNTs as the anode and cathode electrocatalysts. This configuration showcases remarkable capabilities for self‐sustained, precise, and uninterrupted indirect release of H2 stored in NaBH4, even at high current densities of 100 mA cm−2 with a Faraday efficiency approaching 100 %. Additionally, this electrochemical device exhibits significant promise as a fuel cell, with the ability to deliver a maximum power density of 20 mW cm−2. [ABSTRACT FROM AUTHOR]

Transition metal sulfides are emerging as promising anode materials for sodium‐ion batteries (SIBs) due to their high theoretical capacity and low cost, their practical application yet face critical issues of sluggish kinetics and poor cycling stability. In this study, a reliable approach is introduced to overcome these challenges by fabrication of Se0.75‐Fe1‐xS0.25@SC hollow nanospheres thanks to the enriched robust Fe─S─C, C─S, and C─Se bonding, which greatly benefit for enhancing both reaction kinetics and structural stability. Kinetic study combining with in situ characterization reveals that the incorporation of rich‐Se into FeSx induces the formation of cationic Fe and Se vacancies, leading to abundant sites and optimized path for sodium storage. Density functional theory calculations also demonstrate how Se‐rich engineering weakens carbonaceous polar C─S─Fe bonds and accelerates reaction dynamics. The as‐prepared Se0.75‐Fe1‐xS0.25@SC can deliver a high reversible capacity of 515 mAh g−1 at 2 A g−1 over 1250 cycles and achieve superior rate capability with maintaining capacity of 418 mAh g−1 at 10 A g−1. This work pioneers the concept of vacancy‐rich functionalized nanostructures, offering a new pathway for designing advanced electrode materials for energy storage devices. [ABSTRACT FROM AUTHOR]

The advancement of renewable energy is intricately relied on the development of diverse sustainable electrochemical devices. Persuing exceptionally efficient multifunctional electrocatalysts is imperative, as it promises to significantly streamline the electrode fabrication process, thereby enhancing the overall effectiveness of these devices. Herein, a trifunctional electrocatalysts of N‐doped carbon (NC) supported intermetallic PtZn catalyst (PtZn‐IMC@NC) are reported, which performs highly attractively toward the electrocatalysis of glycerol oxidation reactions (GOR), oxygen reduction reactions (ORR), and hydrogen evolution reactions (HER). Its effectiveness are demonstrated as electrocatalysts for both the anode and cathode in a hybrid acid/alkali direct glycerol fuel cell (AA‐DGFC) and a hybrid acid/alkali glycerol‐hydrogen electrolyzer (AA‐GHEC). The AA‐DGFC can release an impressive peak power density of 286.8 mW cm−2, while the AA‐GHEC achieves a noteworthy current density of 100 mA cm−2 at a significantly low applied voltage of 0.47 V. Such intermetallic PtZn‐based trifunctional electrocatalyst empowers them to establish a self‐powered integrated electrochemical device with the AA‐DGFC driving the AA‐GHEC. This setup exemplifies efficient valorization of glycerol into formate in both cells and hydrogen production in electrolyzer device. This study sparks innovation across diverse applications of multifunctional electrocatalysts and infuses renewed momentum into the realm of advanced energy devices. [ABSTRACT FROM AUTHOR]