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Abstract Aqueous zinc‐ion batteries have been regarded as the most potential candidate to substitute lithium‐ion batteries. However, many serious challenges such as suppressing zinc dendrite growth and undesirable reactions, and achieving fully accepted mechanism also have not been solved. Herein, the commensal composite microspheres with α‐MnO2 nano‐wires and carbon nanotubes were achieved and could effectively suppress ZnSO4·3Zn(OH)2·nH2O rampant crystallization. The electrode assembled with the microspheres delivered a high initial capacity at a current density of 0.05 A g−1 and maintained a significantly prominent capacity retention of 88% over 2500 cycles. Furthermore, a novel energy‐storage mechanism, in which multivalent manganese oxides play a synergistic effect, was comprehensively investigated by the quantitative and qualitative analysis for ZnSO4·3Zn(OH)2·nH2O. The capacity contribution of multivalent manganese oxides and the crystal structure dissection in the transformed processes were completely identified. Therefore, our research could provide a novel strategy for designing improved electrode structure and a comprehensive understanding of the energy storage mechanism of α‐MnO2 cathodes.

Rechargeable aqueous ammonium-ion batteries (AAIBs) have attracted more and more attention in energy storage devices because of great safety and cost-effectiveness, as well as excellent rate capability. Recently, it is the main exploration focus for the further improvement of AAIBs to develop suitable electrode materials. Herein, titanic acid and TiO2 were simply synthesized by the facile co-precipitation approach. Titanic acid showed higher capacity of 104.5 mAh g−1 at the 0.1 A g−1 current density, and higher cyclability with the 91.2% capacity retention cycled 1000 cycles at 1 A g−1. Titanic acid is promising as aqueous ammonium-ion batteries with great stability and capacity. [ABSTRACT FROM AUTHOR]

Aqueous zinc batteries with low cost and inherent safety are considered to be the most promising energy storage devices. V2O5/Flake graphite material have been successfully synthesized via high-temperature magnetic stirring and sintering method. V2O5/Flake graphite material were characterized by X-ray diffraction, FESEM, XPS and TGA. The addition of flake graphite not only improves the conductivity of the cathode material, provides more active sites for the Zn2+ insertion/extraction process, but also has a certain isolation effect, avoiding the direct contact between the electrolyte and the V2O5 to cause dissolution. VC51 delivers a high discharge capacity of 328.1 mA h g–1 at 0.1 A g–1, good capacity retention of 81.4% after 300 cycles, shows good cycling stability. [ABSTRACT FROM AUTHOR]

Summary: To address volume expansion from active sulfur and shuttle effect from polysulfides during the electrochemical process of lithium sulfur batteries, nitrogen/sulfur co‐doping porous active carbons (NS‐PACs) derived from biomass cattail were manufactured by one‐step activated hydrothermal method. The effects of N/S atoms co‐doping and the activation of KOH on NS‐PACs were investigated in the macro‐morphology, micro‐structure, and electrochemical performance using scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), Brunauer‐Emmett‐Teller (BET), as well as galvanostatic charge/discharge tests. The experimental data demonstrated that the NS‐PACs show stable foam‐likes porous structure, and the specific surface area (SSA) and pore volumes are 2155.81 m2g−1 and 1.43 cm3g−1, respectively, and reveals perfect N/S atoms doping with S atomic content of 1.4% and N atomic content of 0.78%. Moreover, the initial discharge capacity of NS‐PACs is 1477.8 mAh g−1 at 0.1 C and the extraordinary long‐run cycling stability after 500 cycles reaches 803.4 mAh g−1 at 2.0 C. These outstanding electrochemical performances of NS‐PACs are associated with efficient physical confinement by porous architecture together with the potent chemical adsorption of N/S atoms with polysulfide. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries are more promising and attractive than lithium‐ion batteries owing to a higher charge‐storage capacity. However, their commercial applications are hindered by an undesirable polysulfide shuttling effect during the cycling procedure. Herein, nitrogen and sulfur codoped carbon nanotubes intertwined with flower‐like molybdenum disulfide (NSCNTs/MoS2) were synthesized by using a feasible hydrothermal method and used as effective lithium polysulfides (LiPSs) tamers. The NSCNTs/MoS2 had a strong hybrid structure with strong interfacial interactions for physical confinement, chemical adsorption, and electrocatalytic conversion of intermediate LiPSs during the charge–discharge process. The NSCNTs intensified the flexibility and constructed a conductive framework for rapid ion/electron transfer, whereas the electrocatalysis of MoS2 managed the sulfur reaction chemistry in two ways: it chemically immobilized LiPSs through Li−S bonds and kinetically sped up the sulfur redox reactions. Owing to these merits, the Li–S cell with a NSCNTs/MoS2 host and NSCNTs/MoS2‐coated separator (NSCNTs/MoS2/S‐NM) exhibited a high reversible capacity of 814 mAh g−1 at 1.0 C and long‐lasting cycling durability with an ultralow capacity decay of 0.02 % per cycle over 1000 cycles. Accordingly, rationally integrating the concepts of physical immobilization, chemical capture, and electrocatalysis to establish a multifaced cell structure for the architecture of high‐performance Li–S batteries is a significant strategy. [ABSTRACT FROM AUTHOR]

This work focused on a fabrication of lotus root-like Li 3 V 2 (PO 4) 3 /C composites via a repeated immersion process using the dandelion as a bio-template. The Li 3 V 2 (PO 4) 3 /C composites were characterized using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The Li 3 V 2 (PO 4) 3 /C composites exhibited various structures that were dependent on the various processing techniques. By increasing immersion of the product to three repetitions, a bundle of dandelion carbon fibers was found to be covered by Li 3 V 2 (PO 4) 3 and formed a perfect lotus root-like structure (D-3). The Li 3 V 2 (PO 4) 3 /C composite (D-V) prepared using the vacuum method displayed a dense scrub board-like structure. However, sample D-3 that was prepared using the novel method, exhibited a capacity of 126.8 mAh g−1 at the 1 C rate, a prominent capacity retention of 96.8% after 2000 cycles at the 15 C rate. The experimental results showed that this unique lotus root-like structure is beneficial for improving the capability and cycling stability. [ABSTRACT FROM AUTHOR]

The graphene-like carbon was obtained from macadamia nut shells by an activated hydrothermal method and applied for high-performance supercapacitors. The morphologies and microstructures are investigated by X-ray diffractometer, Raman spectrometer, scanning electron microscopy and transmission electron microscopy. The experimental results show that the obtained carbon exhibits perfect graphene-like structure filled with more micropores and mesopores. The graphene-like carbon displays high surface areas of 1057 m2 g−1. The graphene-like carbon delivers an impressive specific capacitance of 251 F g−1 and has no capacitance loss at the current density of 1 A g−1 after 1000 cycles, which demonstrates the excellent cycle stability and high specific capacitance. The graphene-like carbon derived from macadamia nut shells can be expected for the widespread application of supercapacitors. [ABSTRACT FROM AUTHOR]

A kind of yarn‐like nitrogen‐doped carbon nanotubes microsphere (NSCNT) is synthesized in one‐step synthesis, and sulfur is added by melting immersion to form carbon nanotube microspheres/sulfur composites (NSCNT/S). The morphology, structure and electrochemical property of the obtained NSCNT/S are explored by field‐emission scanning electron microscopy (FESEM), X‐ray diffraction (XRD) and electrochemical tests. The results show that NSCNT possesses a high N content and unique mesoporous carbon framework with large specific surface area of 1029 m2 g−1, which can not only favor rapid electron and Li‐ion transfer but also effectively mitigate dissolved polysulfides via strong chemical and physical adsorption. Due to the synergetic interaction of NSCNT, the NSCNT/S delivers a high initial discharge capacity of 1241.3 mAh g−1 at 0.1 C and large rate capacity of 1175.5 mAh g−1 at 1 C with ultralow capacity decay of 0.1 % per cycle and high areal mass loading of 3.1 mg cm−2. This eco‐friendly NSCNT/S can offer an appealing improvement for the applications of high‐performance lithium‐sulfur batteries. Playing with a yarn ball: yarn‐like nitrogen‐doped carbon nanotube microspheres (NSCNT) are synthesized following a one‐step approach. Sulfur is added by melting immersion to form composites (NSCNT/S). The morphology, structure and electrochemical properties of the obtained NSCNT/S are explored. High discharge capacity and large rate capacity render this eco‐friendly NSCNT/S as an appealing improvement for the applications of high‐performance lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

Li1.1V0.9O2/C microspheres with isomeric core‐shell structure were synthesized by a rapid cooling and subsequent evaporative assembly approach. The prepared Li1.1V0.9O2/C microspheres were characterized by X‐ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM) including elemental mapping analysis, and transmission electron microscopy (TEM). The core‐shell Li1.1V0.9O2/C microspheres display identical composition but distinct texture of cores and shells, which herein is described as isomeric structure. Amorphous carbon nanodots are uniformly dispersed in the crystalline Li1.1V0.9O2 matrix in the core. In the shell however, Li1.1V0.9O2 nanoparticles are embedded in an amorphous carbon network. The Li1.1V0.9O2/C microspheres are tested as active material for anodes in lithium‐ion batteries, and exhibit an excellent reversible capacity of 295 mAh g−1, high capacity retention of 98 % after 100 cycles at 0.2 C and 95 % after 500 cycles at 2 C rate, and deliver wonderful rate capability of 250 mAh g−1 at 5 C. Thus, the Li1.1V0.9O2/C microspheres with isomeric core‐shell structure are promising candidates as anode material for commercial lithium‐ion batteries. In a nutshell: Li1.1V0.9O2/C microspheres are synthesized as anode material for lithium‐ion batteries. The Li1.1V0.9O2/C microspheres display identical composition but distinct texture of cores and shells, which herein is described as isomeric structure. As anodes in lithium‐ion batteries, the microspheres exhibit excellent overall electrochemical performance, rendering this material as promising candidate for the use in commercial lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

A novel, sulfur host, Mn 3 O 4 -CNTs microsphere was prepared by ultrasonic spraying with subsequent impregnation methods and appeared to effectively mitigate the dissolution of intermediate polysulfides from the Li-S cathode. Mn 3 O 4 -CNTs microspheres are caddice-like balls that are interwoven with CNTs that contains Mn 3 O 4 nanoparticles. These novel Mn 3 O 4 -CNTs microspheres were found to exhibit high initial charge and discharge capacities of 1216 and 1227 mAh g −1 at 0.1 C and they exhibited a favorable cycle stability of 1087 mAh g −1 at 0.2 C after 200 cycles. These attributes make this new material a good, potential cathode material for lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

Porous carbons derived from tea seed shells were fabricated through hydrothermal activation and high-temperature activation. The microstructure was investigated via X-ray diffraction, Raman spectrometer, scanning and electron microscopy techniques. The activated carbons show high specific surface areas and developed porosity, and reveal excellent electrochemical performance, especially for the TSSCB samples. When the carbon material TSSCB was applied for lithium-ion batteries, it delivered superior specific charge capacity of 598 mAh g-1 at 0·1C, and showed an impressive rate capability of 440 mAh g-1 at 1C, and maintained high capacity retention of 82·9% even after 500 cycles. Moreover, when the carbon material TSSCB was utilized in supercapacitor, it also exhibited high specific capacitance of 305·7 F g-1 at the current density of 1 A g-1 and the capacitance retention ratio of 98·6% after 10,000 cycles, indicating remarkable cycling stability. Porous carbons derived from tea seed shells are a potential energy storage material. [ABSTRACT FROM AUTHOR]

A kind of nitrogen-doped activated microporous carbon sphere/sulfur composite (NAMCS/S) is deliberately designed and prepared via a controllable solvothermal method and a liquid phase in-situ sulfur deposition technology. The structure characteristic and composition analysis of samples are conducted with X-ray photoelectron spectroscopy (XPS), elemental analysis (EA), field-emission scanning electron microscopy (FESEM) and high resolution transmission electron microscope (HRTEM). The electrochemical performances are characterized by galvanostatic charge-discharge (GCD), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. The results show that the nitrogen-doped activated microporous carbon spheres (NAMCS) present uniform spherical morphology, abundant nitrogen content of 9.64 wt%, and large specific surface areas of 1578.6 m 2 /g. Compared with the activated microporous carbon sphere/sulfur (AMCS/S) composite, the NAMCS/S composite with same sulfur loading of 64 wt% can deliver a higher initial capacity of 1004.6 mAh/g and a stable capacity retention of 79.1% after 100 cycles at 0.1 C rate as well as a remarkable Coulombic efficiency of 93% and relative low capacity decay of 0.2% per cycle. These effective improvements are attributed to the change of surface physicochemical property, chemical interaction between nitrogen functionality and polysulfides and the physical adsorption of abundant microporous structure. [ABSTRACT FROM AUTHOR]

The Li 3 V 2 (PO 4 ) 3 /C composite with hollow coaxial structure has been successfully synthesized via a facile repeated immersion method induced by cotton fibers. The morphologies, structures and properties are investigated by X-ray diffractometer, scanning electron microscopy and galvanostatic charge-discharge tests. Li 3 V 2 (PO 4 ) 3 /C composite displays a unique hollow coaxial structure constructed by hollow carbon fibers filled with Li 3 V 2 (PO 4 ) 3 /C particles inside and coated by Li 3 V 2 (PO 4 ) 3 /C layer outside. Li 3 V 2 (PO 4 ) 3 /C composite exhibits good rate performance with a specific capacity of 115.7 mAh g −1 at 15 C rate between 3.0 and 4.3 V. The improved properties can be attributed to the formation for hollow coaxial structure. [ABSTRACT FROM AUTHOR]