Search

Abstract: Li2CO3‐passivated Li3N with high stability is prepared by aging Li3N powder in dry air, and is then used as an electrode additive for a Li(Li0.18Ni0.15Co0.15Mn0.52)O2 (LLMO) cathode material. The material shows a large irreversible capacity of 800 mA h g−1 during the first charge, with the formation of a Li2N intermediate product. Acting as a Li+ sacrificial salt for a LLMO(+)/graphite(−) Li‐ion battery, 2 wt % Li3N results in a 10 % increase in discharge capacity. The Li2N intermediate product reacts with the electrolyte, forming a uniform and regular surface film on the cathode. Moreover, chemical bonding between LLMO and N improves the electrode stability, resulting in excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: The size and conductivity of the electrode materials play a significant role in the kinetics of sodium‐ion batteries. Various characterizations reveal that size‐controllable VS4 nanoparticles can be successfully anchored on the surface of graphene sheets (GSs) by a simple cationic‐surfactant‐assisted hydrothermal method. When used as an electrode material for sodium‐ion batteries, these VS4@GS nanocomposites show large specific capacity (349.1 mAh g−1 after 100 cycles), excellent long‐term stability (84 % capacity retention after 1200 cycles), and high rate capability (188.1 mAh g−1 at 4000 mA g−1). A large proportion of the capacity was contributed by capacitive processes. This remarkable electrochemical performance was attributed to synergistic interactions between nanosized VS4 particles and a highly conductive graphene network, which provided short diffusion pathways for Na+ ions and large contact areas between the electrolyte and electrode, resulting in considerably improved electrochemical kinetic properties. [ABSTRACT FROM AUTHOR]

A graphene@MoS2@TiO2 hybrid material was successfully prepared by a multi-step solution chemistry method. Few-layered MoS2 nanosheets were impregnated into the nanovoids of mesoporous TiO2 microspheres and the composite was further encapsulated by a graphene layer. When used as a negative electrode material for lithium ion batteries, the nanovoids of TiO2 reduced aggregation of MoS2 and suppressed the large volume change of the active material. Moreover, the dissolution and shuttle of polysulfides were effectively suppressed by the hybrid bonding between MoS2 and TiO2. The nano-sized MoS2 and TiO2 particles encapsulated by a high electronic conductive graphene layer improved the charge transfer reaction of the electrode. Due to these merits, the graphene@MoS2@TiO2 showed a large discharge capacity of 980 mA h g−1 at 0.1 A g−1 current density with a capacity retention of 89% after 200 cycles. Moreover, the material delivered 602 mA h g−1 at 2 A g−1 current density, much larger than 91 mA h g−1 for the pristine MoS2. This demonstrated that the hybrid graphene@MoS2@TiO2 microspheres have great potential as a high-performance negative electrode material for lithium ion batteries. [ABSTRACT FROM AUTHOR]

The practical uses of magnesium-ion batteries are hindered by their poor rate capability and fast capacity decay. Moreover, traditional sodium ion batteries suffer from serious safety problems resulting from the sodium dendrites formed on the anode. In order to circumvent these problems, we designed a highly reversible Na+/Mg2+ hybrid-ion battery composed of a metallic Mg anode, a TiS2 derived titanium sulfide cathode and a 1.0 M NaBH4 + 0.1 M Mg(BH4)2/diglyme hybrid electrolyte. The battery showed remarkable electrochemical performances with a large discharge capacity (200 mA h g−1 at the 1C rate), high rate capability (75 mA h g−1 at the 20C rate) and long cycle life (90% capacity retention after 3000 cycles). Moreover, it exhibited excellent safety properties due to dendrite-free Mg deposition of the anode and the high thermal stability of the cathode. These merits demonstrate the great potential of the reported Na+/Mg2+ hybrid-ion battery for large-scale energy storage. [ABSTRACT FROM AUTHOR]

The demand for large-scale and safe energy storage is increasing rapidly due to the strong push for smartphones and electric vehicles. As a result, Li+/Mg2+ hybrid-ion batteries (LMIBs) combining a dendrite-free deposition of Mg anode and Li+ intercalation cathode have attracted considerable attention. Here, a LMIB with hydrothermal-prepared MoS2 nano flowers as cathode material was prepared. The battery showed remarkable electrochemical properties with a large discharge capacity (243 mAh g−1 at the 0.1 C rate), excellent rate capability (108 mAh g−1 at the 5 C rate), and long cycle life (87.2 % capacity retention after 2300 cycles). Electrochemical analysis showed that the reactions occurring in the battery cell involved Mg stripping/plating at the anode side and Li+ intercalation at the cathode side with a small contribution from Mg2+ adsorption. The excellent electrochemical performance and extremely safe cell system show promise for its use in practical applications. [ABSTRACT FROM AUTHOR]

Li-rich layered oxide Li1.18Ni0.15Co0.15Mn0.52O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium-ion battery and its Na+ storage properties are comprehensively studied in terms of galvanostatic charge-discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium-ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g−1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g−1 for 200 cycles at 5 C rate. Moreover, ex situ ICP-OES suggests interesting mixed-ions migration processes: In the initial two cycles, only Li+ can intercalate into the LNCM cathode, whereas both Li+ and Na+ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge-discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Carbon coated monoclinic Li3V2(PO4)3 cathode material was prepared by the carbothermal reduction method. Raman scattering showed the amorphous nature of the residual carbon in the material. HRTEM and XPS showed that a small amount of carbon penetrated into the Li3V2(PO4)3 crystallites to form a surface carbon layer with thickness about 5–10nm. The material showed a reversible discharge capacity of 120mAhg−1 (C/4 rate), 115mAhg−1 (1C rate) and 110mAhg−1 (2C rate) in the voltage window of 3.0–4.3V, which kept excellent cycle stability in 300 cycles. The material suffered from capacity loss in the initial ten charge–discharge cycles. The irreversible capacity loss was mainly related to the progressive formation of a solid electrolyte interface (SEI) film which was clearly observed by HRTEM. FTIR analysis showed that the chemical species of the SEI film mainly contained some organic compounds such as ROCO2Li, RCO2Li, and aliphatic, as well as some inorganic compounds such as Li2CO3, Li x PF y or Li x PO y F z . The SEI film tended to be stabilized in the initial several cycles, which led to excellent electrochemical performance during long term cycling. [Copyright &y& Elsevier]

[Display omitted] • Single-crystal high-entropy (oxy)hydroxides were prepared through multication exchange. • The import of Al in a multicomponent (oxy)hydroxides would induce the formation of nanoporous structure. • The mixing of Ru with other metallic elements moderates the electronic structure for better OER performance. • This dynamic crystal growth strategy could extend to fabricate diversiform (oxy)hydroxides. High-entropy materials are new-fashioned electrocatalysts due to their interesting "cocktail effect". However, it is still a great challenge to synthesize single-crystal high-entropy nanomaterials such as (oxy)hydroxides due to the different crystal growth mode for different elements. Herein, we design a dynamic crystal growth strategy by multi-cation exchange to fabricate single-crystal high-entropy (oxy)hydroxides nanosheets. Nanoporous morphology can be achieved by incorporating Al ion into the multicomponent (oxy)hydroxides system after a reversible Al insertion-dissolution process. When adopted as potential electrocatalysts for oxygen evolution reaction (OER), we find that the seven-component ZnVNiCoFeAlRu-OHs single-crystal nanoporous nanosheets display a significantly improved OER performance with a low overpotential of 229 mV at 10 mA cm−2 and a shallow Tafel slope of 39.3 mV dec−1. Both XPS and DFT calculation reveal that Ru acted an electron dedicator could effectively moderate the overall electronic structures for better OER performance. This work develops an entropy and enthalpy driven multi-cation exchange strategy for synthesizing a library of single-crystal high-entropy (oxy)hydroxides for various applications. [ABSTRACT FROM AUTHOR]

Bimetallic transition metal chalcogenides (TMCs) materials have emerged as attractive anodes for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) because of the high intrinsic electronic conductivity, rich redox sites and unique reaction mechanism. In this work, we report the synthesis and electrochemical properties of a novel bimetallic TMCs material CuSbSe 2 . The as-prepared anode delivers a high reversible capacity of 545.6  mA h g -1 for SIBs and 592.6  mA h g -1 for LIBs at a current density of 0.2 A g -1 , and an excellent rate capability of 425.9  mA h g -1 at 20 A g -1 for SIBs and 226.0  mA h g -1 at 10 A g -1 for LIBs without any common-used surface modification or carbonaceous compositing. In addition, ex situ X-ray diffraction (XRD) and High-resolution transmission electron microscopy (HRTEM) reveal a combined conversion-alloying reaction mechanism of LIBs and NIBs. Our findings suggest bimetallic CuSbSe 2 could be a potential anode material for both SIBs and LIBs., (© 2022 Wiley-VCH GmbH.)

We have synthesized a series of Li 1+ x (Ni 0.5 Mn 0.5 ) 1- x O 2 (LNMO) materials to study the influence of excess lithium ions on the structure and electrochemical behaviors of nickel-manganese-based layered compounds. The increasing content of Li + ions in the transition-metal (TM) layer leads to the departure of the follower-like clusters to Ni-rich and Mn-rich clusters. The Ni 2+ ions in the Li layer couple with adjacent transition-metal ions via strong 180° exchange interactions and moderate the local structure, which leads to magnetic clusters with finite size. Electrochemical performance shows that appropriate Ni 2+ ions could improve the cycle stability without decreasing the rate capability. Among them, Li 1.1 Ni 0.45 Mn 0.45 O 2 shows a rate capability of 76 mAh g -1 at 1000 mA g -1 and a lifespan of 300 cycles at 200 mA g -1 . This work shows that structure moderation has an essential impact on its electrochemical performance. Besides this, the crystal and magnetic combined methods we use could offer a better way of studying cathode materials.

Reversible aqueous zinc-ion batteries (ZIBs) have great potential for large-scale energy storage owing to their low cost and safety. However, the lack of long-lifetime positive materials severely restricts the development of ZIBs. Herein, we report NaV 6 O 15 microflowers as a cathode material for ZIBs with excellent electrochemical performance, including a high specific capacity of ∼300 mA h g -1 at 100 mA g -1 and 141 mA h g -1 maintained after 2000 cycles at 5 A g -1 with a capacity retention of ∼107%. The high diffusion coefficient and stable tunneled structure of NaV 6 O 15 facilitate Zn 2+ intercalation/extraction and long-term cycle stability., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Rechargeable aqueous zinc ion batteries (ZIBs), owing to their low-cost zinc metal, high safety and nontoxic aqueous electrolyte, have the potential to accelerate the development of large-scale energy storage applications. However, the desired development is significantly restricted by cathode materials, which are hampered by the intense charge repulsion of bivalent Zn 2+ . Herein, the as-prepared VO 2 (A) hollow spheres via a feasible hydrothermal reaction exhibit superior zinc ion storage performance, large reversible capacity of 357 mA h g -1 at 0.1 A g -1 , high rate capability of 165 mA h g -1 at 10 A g -1 and good cycling stability with a capacity retention of 76% over 500 cycles at 5 A g -1 . Our study not only provides the possibility of the practical application of ZIBs, but also brings a new prospect of designing high-performance cathode materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Li 2 CO 3 -passivated Li 3 N with high stability is prepared by aging Li 3 N powder in dry air, and is then used as an electrode additive for a Li(Li 0.18 Ni 0.15 Co 0.15 Mn 0.52 )O 2 (LLMO) cathode material. The material shows a large irreversible capacity of 800 mA h g -1 during the first charge, with the formation of a Li 2 N intermediate product. Acting as a Li + sacrificial salt for a LLMO(+)/graphite(-) Li-ion battery, 2 wt % Li 3 N results in a 10 % increase in discharge capacity. The Li 2 N intermediate product reacts with the electrolyte, forming a uniform and regular surface film on the cathode. Moreover, chemical bonding between LLMO and N improves the electrode stability, resulting in excellent electrochemical performance., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The size and conductivity of the electrode materials play a significant role in the kinetics of sodium-ion batteries. Various characterizations reveal that size-controllable VS 4 nanoparticles can be successfully anchored on the surface of graphene sheets (GSs) by a simple cationic-surfactant-assisted hydrothermal method. When used as an electrode material for sodium-ion batteries, these VS 4 @GS nanocomposites show large specific capacity (349.1 mAh g -1 after 100 cycles), excellent long-term stability (84 % capacity retention after 1200 cycles), and high rate capability (188.1 mAh g -1 at 4000 mA g -1 ). A large proportion of the capacity was contributed by capacitive processes. This remarkable electrochemical performance was attributed to synergistic interactions between nanosized VS 4 particles and a highly conductive graphene network, which provided short diffusion pathways for Na + ions and large contact areas between the electrolyte and electrode, resulting in considerably improved electrochemical kinetic properties., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Ultrathin TiO 2 -B nanowires with a naked (-110) surface were prepared by a hydrothermal process and used as the anode material for Mg-ion batteries. The material delivered a reversible Mg 2+ ion capacity of 110 mA h g -1 at the 0.1C rate. Excellent cycling stability was achieved with a small capacity-fading rate of 0.08% per cycle. In addition, a discharge capacity of 34 mA h g -1 was obtained at the 50C rate, demonstrating the material's excellent high rate capability. First-principles calculations showed that Mg 2+ ions hardly penetrated into the TiO 2 -B lattice because of a very large Mg 2+ ion diffusion barrier of 0.63 eV. Instead, the Mg 2+ ions were stored at the 4-coordinated vacancies of TiO 2 -B nanowire (-110) surfaces. The adsorbed Mg 2+ ions were bonded with unpaired surface oxygen atoms. Meanwhile, a small amount of electrons were transferred from the O-2p state to the Ti-3d state.

The demand for large-scale and safe energy storage is increasing rapidly due to the strong push for smartphones and electric vehicles. As a result, Li + /Mg 2+ hybrid-ion batteries (LMIBs) combining a dendrite-free deposition of Mg anode and Li + intercalation cathode have attracted considerable attention. Here, a LMIB with hydrothermal-prepared MoS 2 nano flowers as cathode material was prepared. The battery showed remarkable electrochemical properties with a large discharge capacity (243 mAh g -1 at the 0.1 C rate), excellent rate capability (108 mAh g -1 at the 5 C rate), and long cycle life (87.2 % capacity retention after 2300 cycles). Electrochemical analysis showed that the reactions occurring in the battery cell involved Mg stripping/plating at the anode side and Li + intercalation at the cathode side with a small contribution from Mg 2+ adsorption. The excellent electrochemical performance and extremely safe cell system show promise for its use in practical applications., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Li-rich layered oxide Li1.18 Ni0.15 Co0.15 Mn0.52 O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium-ion battery and its Na(+) storage properties are comprehensively studied in terms of galvanostatic charge-discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium-ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g(-1) at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g(-1) for 200 cycles at 5 C rate. Moreover, ex situ ICP-OES suggests interesting mixed-ions migration processes: In the initial two cycles, only Li(+) can intercalate into the LNCM cathode, whereas both Li(+) and Na(+) work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge-discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium-ion batteries., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)