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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]

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]

Cost-effective catalysts are of key importance to the successful deployment of microbial fuel cells (MFCs) for electricity generation from organic wastes. Herein, a novel catalyst prepared by one-step synthesis strategy is reported. The catalyst features N-doped bamboo-like carbon nanotube (BCNT) in which CoNi-alloy is encapsulated at the end and/or the middle section of the tube with many graphene layers inside inner cavities of BCNT (N-G@CoNi/BCNT). The prepared N-G@CoNi/BCNT exhibits a high oxygen reduction reaction (ORR) activity with an early onset potential of 0.06 V vs. Ag/AgCl and a comparable exchange current density to that of commercial Pt/C. The excellent catalytic activity is further evidenced by a high electron transfer number of 3.63. When being applied in MFCs, the N-G@CoNi/BCNT yields an average current density of 6.7 A m −2 , slightly lower than that of Pt/C but with a less mass transfer potential loss. The cost of the N-G@CoNi/BCNT for constructing a 1-m 2 cathode electrode is 200 times lower than that of Pt/C. With such a competitive price and excellent electrocatalytic-activity resulting from its unique morphology, CoNi-alloy/nitrogen dopants, considerable specific surface area, and carbon-coated alloy/graphene hybridization, the present catalyst is a promising candidate for ORR catalysts in MFCs for energy recovery from wastes. [ABSTRACT FROM AUTHOR]

WS2 nanosheets hold great promise for a variety of applications yet faces a grand challenge in terms of large‐scale synthesis. We report a reliable, scalable, and high‐yield (>93 %) synthetic strategy to fabricate WS2 nanosheets, which exhibit highly desirable electrocatalytic properties toward both the alkaline sulfion (S2−) oxidation reaction (SOR) and the acidic hydrogen evolution reaction (HER). The findings prompted us to develop a hybrid alkali‐acid electrochemical cell with the WS2 nanosheets as bifunctional electrode catalysts of alkaline anodic SOR and acidic cathodic HER. The proof‐of‐concept device holds promise for self‐power or low‐electricity electrolytic H2 generation and environmentally friendly recycling of sulfion with enhanced electron utilization efficiency. [ABSTRACT FROM AUTHOR]

WS2 nanosheets hold great promise for a variety of applications yet faces a grand challenge in terms of large‐scale synthesis. We report a reliable, scalable, and high‐yield (>93 %) synthetic strategy to fabricate WS2 nanosheets, which exhibit highly desirable electrocatalytic properties toward both the alkaline sulfion (S2−) oxidation reaction (SOR) and the acidic hydrogen evolution reaction (HER). The findings prompted us to develop a hybrid alkali‐acid electrochemical cell with the WS2 nanosheets as bifunctional electrode catalysts of alkaline anodic SOR and acidic cathodic HER. The proof‐of‐concept device holds promise for self‐power or low‐electricity electrolytic H2 generation and environmentally friendly recycling of sulfion with enhanced electron utilization efficiency. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable batteries have attracted attention owning to their advantages of safety, low cost, and sustainability, while the limited electrochemical stability window (1.23 V) of water leads to their failure in competition with organic‐based lithium‐ion batteries. Herein, we report an alkali–acid Zn–PbO2 hybrid aqueous battery obtained by coupling an alkaline Zn anode with an acidic PbO2 cathode. It shows the capability to deliver an impressively high open‐circuit voltage (Voc) of 3.09 V and an operate voltage of 2.95 V at 5 mA cm−2, thanks to the contribution of expanding the voltage window and the electrochemical neutralization energy from the alkali–acid asymmetric‐electrolyte hybrid cell. The hybrid battery can potentially deliver a large area capacity over 2 mAh cm−2 or a high energy density of 252.39 Wh kg−1 and shows almost no fading in area capacity over 250 charge–discharge cycles. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable batteries have attracted attention owning to their advantages of safety, low cost, and sustainability, while the limited electrochemical stability window (1.23 V) of water leads to their failure in competition with organic‐based lithium‐ion batteries. Herein, we report an alkali–acid Zn–PbO2 hybrid aqueous battery obtained by coupling an alkaline Zn anode with an acidic PbO2 cathode. It shows the capability to deliver an impressively high open‐circuit voltage (Voc) of 3.09 V and an operate voltage of 2.95 V at 5 mA cm−2, thanks to the contribution of expanding the voltage window and the electrochemical neutralization energy from the alkali–acid asymmetric‐electrolyte hybrid cell. The hybrid battery can potentially deliver a large area capacity over 2 mAh cm−2 or a high energy density of 252.39 Wh kg−1 and shows almost no fading in area capacity over 250 charge–discharge cycles. [ABSTRACT FROM AUTHOR]

• Bifunctional electrocatalyst of Pd decorating P, N-codoped carbon nanostructures. • A hybrid acid/alkali cell for energy-saving and self-powered generation of H 2. • Indirect releasing H 2 stored in hydrazine by an electrochemical strategy. • Efficient, controllable and continuous release high-purity H 2 from H 2 carrier. Liquid-phase hydrogen (H 2) carriers have received widespread attention owing to their convenient and safe storage and transportation of H 2. Among the various liquid-phase H 2 carriers, hydrazine (N 2 H 4) shows promising applications due to its ability to release H 2 in aqueous solutions via the dehydrogenation process with the assistance of suitable catalysts, which yet produces N 2 /H 2 mixture gas and thus require additional high-energy purification process. In this work, we propose a self-powered electrochemical strategy to indirectly release high-purity H 2 stored in N 2 H 4 by developing a hybrid acid/alkali electrochemical cell, which is set up by coupling alkaline anode for N 2 H 4 electrooxidation reaction (HzOR) with acidic cathode for hydrogen evolution reaction (HER), respectively. For this purpose, Pd nanoparticles uniformly decorating P, N-codoped hollow dodecahedron carbon nanostructures (Pd/PNC) is prepared as bifunctional electrocatalyst for both HzOR and HER, which exhibits high electrocatalytic activity and robust stability. Density functional theory (DFT) calculations imply that P, N-codoping substrate of Pd is conductive to optimize adsorption/desorption sites upon electrocatalysis of HzOR and HER by lowing Gibbs free energy and improving activity. The as-assembled hybrid acid/alkali cell is capable of delivering a maximum power density of 18.2 mW cm−2 and can run stably for 120 h, implementing H 2 generation in a voltage or power controllable manner. This work may inspire exploring the way for efficient, energy-saving, and continuous generation of high-purity H 2. [ABSTRACT FROM AUTHOR]

Zn-quinone batteries, with the merit of high reversibility, show great potential in the energy storage and conversion system, but the low working voltage and power density limit their application. We here report a rechargeable asymmetric alkali-acid electrolyte Zn-quinone battery (AAAZQB, 3AZQB) with the Zn anode in alkali and the highly reversible quinone cathode in acid. The elaborate asymmetric alkali-acid electrolyte design, enables the redox of Zn and quinone can act in their optimal conditions, the electrochemical neutralization energy can be harvested simultaneously. As a result, the 3AZQB delivers an open circuit voltage of 1.95 V, a peak power density up to 315 mW cm−2 and a highly strong stability with a reversible charging/discharging voltage gap of 200 mV, which are much better than those of Zn-air batteries and Zn-quinone batteries reported before. Image 1 • Zn-quinone battery was employed to harvest electrochemical neutralization energy. • An open circuit voltage of 1.95 V can be achieved. • The device shows a power density up to 315 mW cm−2. • A long-term stability with ultralow voltage gap of 200 mV is realized. [ABSTRACT FROM AUTHOR]

• A sophisticated Ru/3DNCN catalyst were prepared through the template-assisted method. • Ru/3DNCN holds unique 3D porous interconnected structure and plenty of active sites. • Ru/3DNCN exhibits a top-level HER activity and robust stability in a wide pH range. • A Zn-H 2 fuel cell was assembled for hydrogen evolution and electricity generation. The rational design of a highly active, stable and Pt-free electrocatalyst for hydrogen evolution reaction (HER) is critical to the development of renewable energy conversion systems but extremely challenging. Herein, a facile top-down strategy is presented to synthesize ultrafine Ru nanoparticles confined in three-dimensional (3D) porous nitrogen-doped carbon nanosheets (Ru/3DNCN). Compared with the state-of-the-art Pt/C catalyst, the Ru/3DNCN exhibits significantly boosted HER activity and stability over a wide pH range, which only requires the overpotential as low as 37 mV, 66 mV, and 17 mV to achieve a current density of 10 mA cm−2 in 0.5 M H 2 SO 4 , 1.0 M PBS, and 1.0 M KOH, respectively. Moreover, an alkali-acid Zn-H 2 battery is assembled by using the Ru/3DNCN as acid cathode and Zn plate as alkaline anode. Such hybrid battery can fulfill simultaneously hydrogen evolution and electricity generation, thanks to harvesting energy from both neutralization and Zn oxidation. [ABSTRACT FROM AUTHOR]

• A tri-profitable electrochemical cell for energy saving, hydrogen production, gluconate production. • Bifunctional high-activity electrocatalyst of Fe 0.1 -CoSe 2. • Acidic hydrogen evolution and alkaline glucose oxidation. • Electrochemical neutralization energy assisted aqueous electrochemical system. Electrolytic synthesis shows great promise to address the pressing environmental and energy issues by synergy with the ever increasing renewable energy. In this article, we report a tri-profitable alkaline-acidic asymmetric electrolytic cell (3A-EC) by coupling glucose oxidation reaction (GOR) in alkaline anode with hydrogen evolution reaction (HER) in acidic cathode. We design and fabricate bifunctional electrode with iron doped cobalt diselenide nanowires on conductive carbon cloth (Fe 0.1 -CoSe 2 /CC), which shows highly attractive electrocatalytic activity and stability for GOR in alkali and HER in acid, respectively. The as-built 3A-EC only requires an applied voltage of 0.72 V to achieve an electrolytic current density of 10 mA cm−2 for H 2 and gluconate generation, thanks to successfully harvesting electrochemical energy from both glucose oxidation and neutralization. The present work presents an innovative strategy of killing three birds with one stone for saving energy and generating two value-added products. [ABSTRACT FROM AUTHOR]

A novel exfoliated NbS 2 nanosheets produced via liquid exfoliation method exhibited an excellent catalytic activity for nitrogen reduction reaction. • A novel exfoliated NbS 2 nanosheets was produced via liquid exfoliation method. • Exfoliated NbS 2 nanosheets exhibited an excellent catalytic activity for NRR. • The Nb4+ species of exfoliated NbS 2 nanosheets was acted as active sites. • Exfoliated NbS 2 nanosheets was acted as the cathode for a Zn-N 2 battery. • Solar-driven NRR-OER device was achieved with exfoliated NbS 2 nanosheets. Electrochemical nitrogen reduction reaction (NRR) under mild conditions is an attractive prospect for ammonia synthesis. However, this process faces with poor ammonia yield rate and low Faradic efficiency. Herein, we developed exfoliated metallic niobium disulfate (NbS 2) nanosheets for an electrochemical NRR. Owing to more exposed active sites and high electron transfer ability, the exfoliated NbS 2 nanosheets show an extraordinary activity for electrochemical NRR. A high Faradaic efficiency of 10.12 % with an ammonia yield rate of 37.58 μg h−1 mg−1 cat is achieved at −0.5 V versus reversible hydrogen electrode (RHE). The Nb4+ species of exfoliated NbS 2 are confirmed as active sites for NRR. When the exfoliated NbS 2 nanosheets are further assembled into a Zn-N 2 battery and serve as the cathode, an energy density of 714 mA h g−1 with a power density of 0.31 mW cm−2 is achieved. Notably, electrochemical NRR on exfoliated NbS 2 nanosheets can be further driven by solar energy. [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]