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1.
Small ; : e2404215, 2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38973090

ABSTRACT

Aqueous nickel-ion batteries (ANIBs) as an emerging energy storage device attracted much attention owing to their multielectron redox reaction and dendrite-free Ni anode, yet their development is hindered by the divalent properties of Ni2+ and the lack of suitable cathode materials. Herein, a hydrated iron vanadate (Fe2V3O10.5∙1.5H2O, FOH) with a preferred orientation along the (200) plane is innovatively proposed and used as cathode material for ANIBs. The FOH cathode exhibits a remarkable capacity of 129.3 mAh g-1 at 50 mA g-1 and a super-high capacity retention of 95% at 500 mA g-1 after 700 cycles. The desirable Ni2+ storage capacity of FOH can be attributed to the preferentially oriented and tunnel structures, which offer abundant reaction active planes and a broad Ni2+ diffusion path, the abundant vacancies and high specific surface area further increase ion storage sites and accelerate ion diffusion in the FOH lattice. Furthermore, the Ni2+ storage mechanism and structural evolution in the FOH cathode are explored through ex situ XRD, ex situ Raman, ex situ XPS and other ex situ characteristics. This work opens a new way for designing novel cathode materials to promote the development of ANIBs.

2.
ACS Appl Mater Interfaces ; 16(26): 34020-34029, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961571

ABSTRACT

Rechargeable aqueous Zn-ion batteries with a Zn anode hold great promise as promising candidates for advanced energy storage systems. The construction of protective layer coatings on Zn anode is an effective way to suppress the growth of Zn dendrites and water-induced side reactions. Herein, we reported a series of UIO-66 materials with different concentrations of reduced graphene oxide (rG) coated onto the surface of Zn foil (Zn@UIO-66/rGx; x = 0.05, 0.1, and 0.2). Benefiting from the synergistic effect of UIO-66 and rG, symmetric cells with Zn@UIO-66/rGx (x = 0.1) electrodes exhibit excellent reversibility (e.g., long cycling life over 1100 h at 1 mA cm-2/1 mAh cm-2) and superior rate capability (e.g., over 1100 and 400 h at 5 mA cm-2/2.5 mAh cm-2 and 10 mA cm-2/5 mAh cm-2, respectively). When the Zn@UIO-66/rG0.1 anode was paired with the NaV3O8·1.5H2O (NVO) cathode, the Zn@UIO-66/rG0.1||NVO cell also delivered a high reversible capacity of 189.9 mAh g-1 with an initial capacity retention of 61.3% after 500 cycles at 1 A g-1, compared to the bare Zn||NVO cell with only 92 cycles.

3.
J Colloid Interface Sci ; 676: 197-206, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39024820

ABSTRACT

The efficient recycling of waste graphite anode from used lithium-ion batteries (LIBs) has attracted considerable concerns mainly owing to the environment protection and reutilization of resources. Herein, we reported a rational and facile strategy for the synthesis of holey graphite coated by carbon (hG0.01@C0.10) through the separation, purification and creation of holey structures of waste graphite by using NaOH and carbon-coating by using phenolic resin. The holey structures facilitate the hG0.01@C0.10 with the quick penetration of electrolytes and rapid diffusion of Li+. The carbon coating is more favorable for hG0.01@C0.10 with improved electronic conductivity and less alleviated volume during the cycles. Benefiting from the synergistic effect of holey structures and carbon coating, the hG0.01@C0.10 as anode for LIBs displays a high reversible capacity of 377.6 mAh g-1 at 0.5 C and superior rate capabilities (e.g., 348.0 and 274.7 mAh g-1 at 1 and 2 C, respectively) and maintains a high reversible capacity of 278.7 mAh g-1 at 1 C after 300 cycles with an initial capacity retention of 80.0 %.

4.
iScience ; 27(6): 109961, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38947504

ABSTRACT

The causality between circulating proteins and thyroid cancer (TC) remains unclear. We employed five large-scale circulating proteomic genome-wide association studies (GWASs) with up to 100,000 participants and a TC meta-GWAS (nCase = 3,418, nControl = 292,703) to conduct proteome-wide Mendelian randomization (MR) and Bayesian colocalization analysis. Protein and gene expressions were validated in thyroid tissue. Through MR analysis, we identified 26 circulating proteins with a putative causal relationship with TCs, among which NANS protein passed multiple corrections (P BH = 3.28e-5, 0.05/1,525). These proteins were involved in amino acids and organic acid synthesis pathways. Colocalization analysis further identified six proteins associated with TCs (VCAM1, LGMN, NPTX1, PLEKHA7, TNFAIP3, and BMP1). Tissue validation confirmed BMP1, LGMN, and PLEKHA7's differential expression between normal and TC tissues. We found limited evidence for linking circulating proteins and the risk of TCs. Our study highlighted the contribution of proteins, particularly those involved in amino acid metabolism, to TCs.

5.
Chem Soc Rev ; 53(13): 6735-6778, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38826108

ABSTRACT

Chiral 1,2-bis(2,5-diphenylphospholano)ethane (Ph-BPE) is a class of optimal organic bisphosphine ligands with C2-symmetry. Ph-BPE with its excellent catalytic performance in asymmetric synthesis has attracted much attention of chemists with increasing popularity and is growing into one of the most commonly used organophosphorus ligands, especially in asymmetric catalysis. Over two hundred examples have been reported since 2012. This review presents how Ph-BPE is utilized in asymmetric synthesis and how powerful it is as a chiral ligand or even a catalyst in a wide range of reactions including applications in the total synthesis of bioactive molecules.

6.
Biol Trace Elem Res ; 2024 Mar 16.
Article in English | MEDLINE | ID: mdl-38492120

ABSTRACT

Exposure to metal mixtures compromises the immune system, with the complement system connecting innate and adaptive immunity. Herein, we sought to explore the relationships between blood cell metal mixtures and the third and fourth components of serum complement (C3, C4). A total of 538 participants were recruited in November 2017, and 289 participants were followed up in November 2021. We conducted a cross-sectional analysis at baseline and a longitudinal analysis over 4 years. Least Absolute Shrinkage and Selection Operator (LASSO) was employed to identify the primary metals related to serum C3, C4; generalized linear model (GLM) was further used to evaluate the cross-sectional associations of the selected metals and serum C3, C4. Furthermore, participants were categorized into three groups according to the percentage change in metal concentrations over 4 years. GLM was performed to assess the associations between changes in metal concentrations and changes in serum C3, C4 levels. At baseline, each 1-unit increase in log10-transformed in magnesium, manganese, copper, rubidium, and lead was significantly associated with a change in serum C3 of 0.226 (95% CI: 0.146, 0.307), 0.055 (95% CI: 0.022, 0.088), 0.113 (95% CI: 0.019, 0.206), - 0.173 (95% CI: - 0.262, - 0.083), and - 0.020 (95% CI: - 0.039, - 0.001), respectively. Longitudinally, decreased copper concentrations were negatively associated with an increment in serum C3 levels, while decreased lead concentrations were positively associated with an increment in serum C3 levels. However, no metal was found to be primarily associated with serum C4 in LASSO, so we did not further explore the relationship between them. Our research indicates that copper and lead may affect complement system homeostasis by influencing serum C3 levels. Further investigation is necessary to elucidate the underlying mechanisms.

7.
Angew Chem Int Ed Engl ; 62(32): e202305449, 2023 Aug 07.
Article in English | MEDLINE | ID: mdl-37338222

ABSTRACT

Recent years have witnessed marked progress in the efficient synthesis of various enantioenriched 1,2,3,4-tetrahydroquinoxalines. However, enantio- and diastereoselective access to trans-2,3-disubstituted 1,2,3,4-tetrahydroquinoxalines remains much less explored. Herein we report that a frustrated Lewis pair-based catalyst generated via in situ hydroboration of 2-vinylnaphthalene with HB(C6 F5 )2 allows for the one-pot tandem cyclization/hydrosilylation of 1,2-diaminobenzenes and 1,2-diketones with commercially available PhSiH3 to exclusively afford trans-2,3-disubstituted 1,2,3,4-tetrahydroquinoxalines in high yields with excellent diastereoselectivities (>20 : 1 dr). Furthermore, this reaction can be rendered asymmetric by using an enantioenriched borane-based catalyst derived from HB(C6 F5 )2 and a binaphthyl-based chiral diene to give rise to enantioenriched trans-2,3-disubstituted 1,2,3,4-tetrahydroquinoxalines in high yields with almost complete diastereo- and enantiocontrol (>20 : 1 dr, up to >99 % ee). A wide substrate scope, good tolerance of diverse functionality and up to 20-gram scale production are demonstrated. The enantio- and diastereocontrol are achieved by the judicious choice of borane catalyst and hydrosilane. The catalytic pathway and the origin of the excellent stereoselectivity are elucidated by mechanistic experiments and DFT calculations.

8.
Nanoscale ; 15(14): 6722-6731, 2023 Apr 06.
Article in English | MEDLINE | ID: mdl-36939131

ABSTRACT

The commercialization of aqueous zinc-ion batteries (AZIBs) has been hindered by the obsession with Zn-metal anode, just like the early days of lithium-ion batteries. Developing Zn-metal free aqueous batteries (ZFABs) with superior Zn-supplied cathodes is a promising way to escape this predicament. Herein, a novel mixed transition-metal spinel, Zn3V2MoO8, has been synthesized via a sol-gel technique and proposed as a Zn-supplied cathode material. Utilizing the synergistic effect of vanadium and molybdenum, Zn3V2MoO8 can provide a high capacity of 360.3 mA h g-1 at 100 mA g-1, which is the state-of-the-art in existing Zn-supplied cathodes, and the capacity retention is 82% over 700-4500 cycles at 10 A g-1. The mechanism is that Zn3V2MoO8 undergoes a phase transition to Zny(V,Mo)2O5-x·nH2O in the initial charge, and then protons and zinc ions intercalate/deintercalate concurrently into/from the new host. To construct ZFABs with a Zn3V2MoO8 cathode, two non-zinc materials (brass and 9,10-anthraquinone) are used as anodes. Thereby, the Zn3V2MoO8||9,10AQ battery reveals a more satisfactory electrochemical performance, with a stable capacity of 100.4 mA h g-1 lasting for 200 cycles, which provides a feasible scheme for the practical application of AZIBs.

9.
ACS Appl Mater Interfaces ; 14(51): 56715-56724, 2022 Dec 28.
Article in English | MEDLINE | ID: mdl-36525290

ABSTRACT

O'3-Na3Ni2SbO6 with a honeycomb cation order, as a potential cathode, presents simplified phase-transition steps and a high average voltage. To mitigate the intrinsic phase irreversibility, Mg, Zn, and Co have been introduced to displace part of the Ni, which inevitably reduces the theoretical capacity related to the Ni2+/Ni3+ redox reaction. In this work, an unusual dual-site substitution is carried out to increase the P'3-O'3 structure reversibility without sacrificing the practical capacity. In addition, it is found that special stacking faults along the c-axis direction can be induced by doping to result in incomplete Sb/Ni disorder, though the honeycomb order remains in every TM (transition-metal) layer. The codoped Na2.85Cs0.15Ni1.9Mg0.1SbO6 has a high degree of disorder, which breaks the ideal monoclinic symmetry (C2/m) and partly upgrades its structure to higher-symmetry models. Profiting from the influence of stacking disorder and doping ions on the coordination environment around Na, more gradual and smaller variations of the lattice parameters appear upon Na-ion extraction/insertion. Consequently, this cathode displays a high initial discharge capacity (120 mAh g-1), long-term cycling stability, and excellent rate performance (66 mAh g-1 under 10 C). These findings reveal that not only a full TM-disordered arrangement but also this incomplete stacking disorder can effectively improve the performance of a layered cathode.

10.
Nanoscale ; 14(45): 17013-17026, 2022 Nov 24.
Article in English | MEDLINE | ID: mdl-36367121

ABSTRACT

Improving the anode materials for lithium-ion batteries with a long activation process, poor cycle stability, and low Coulomb efficiency is of great significance for developing novel high-performance anode materials. Orthorhombic LiVMoO5 with high specific capacity was applied to the anode field of lithium-ion battery for the first time. However, the activation process led to its poor cyclic performance. By adopting a novel nano-transformation treatment process in a water and oxygen environment, we effectively avoided the long-term activation process. The specially treated LiVMoO5 electrode (STLVME) exhibited excellent reversible specific capacity (∼1100 mA h g-1) and rate cycle stability (capacity retention rate ∼100%). Furthermore, GITT and EIS also showed that compared with the primitive LiVMoO5 electrode (LVME), smaller internal resistance and a higher Li+ diffusion coefficient were caused using the novel treatment process, significantly improving the rate cycle stability. Using in situ XRD and ex situ characterization, we illustrated the lithium storage mechanism of LVME and STLVME. In addition, the practical application potential of LVME and STLVME was also explored by assembling the full cells. Because the long-term activation process was effectively avoided, the full-cell exhibited amazing cycle stability, indicating that STLVME can be considered a promising potential anode for practical applications in energy storage devices.

11.
Nanoscale ; 14(29): 10428-10438, 2022 Jul 28.
Article in English | MEDLINE | ID: mdl-35815897

ABSTRACT

Binary transition metal oxides (BTMOs) are regarded as potential anode materials for lithium-ion batteries (LIBs) owing to their low cost, high specific capacities, and environmental friendliness. In this work, MnV2O6 nanoflakes are successfully synthesized by a facile hydrothermal method. When evaluated as an anode material for LIBs, benefiting from the activation process, the as-prepared MnV2O6 nanoflake electrode delivers a high reversible specific capacity of 1439 mA h g-1 after 300 cycles at a current density of 200 mA g-1, and especially presents a specific capacity of 1010 mA h g-1 after 700 cycles at a higher current density of 1 A g-1. Furthermore, MnV2O6 shows a pleasurable rate capability; a reversible specific capacity of 867 mA h g-1 can be obtained at a current density of 2000 mA g-1, and when the current density is returned to 200 mA g-1 and continues for another 80 cycles, the specific capacity can still reach 1499 mA h g-1. Meanwhile, the morphology variation and electrochemical kinetic behavior of the MnV2O6 electrode during cycling are scrutinized in detail. After that, the electrochemical reaction mechanism of MnV2O6 during the discharge/charge process is corroborated by in situ X-ray diffraction (XRD), which involves the coexistence of a conversion reaction and solid solution behavior. The practical application of MnV2O6 nanoflakes as an anode material is examined as well. Sure enough, the NCM811//MnV2O6 full-cell exhibits excellent lithium-storage performance.

12.
Chem Commun (Camb) ; 58(63): 8736-8753, 2022 Aug 04.
Article in English | MEDLINE | ID: mdl-35861166

ABSTRACT

Supramolecular gels, as a fascinating and useful class of soft materials, constructed from low-molecular-weight gelators via noncovalent interactions have attracted increasing attention in the past few decades. Dendrimers and dendrons are highly branched and monodisperse macromolecules with a well-defined three-dimensional architecture and multiple surface functionalities. In recent years, poly(benzyl ether) dendrimers and dendrons are found to be powerful candidates for constructing gel phase materials in organic or aqueous media due to the advantages of capability of forming multiple noncovalent interactions and significant steric impact. In this Feature Article, we provide a comprehensive overview of recent progress in supramolecular gels involving poly(benzyl ether) dendritic molecules. Firstly, we outline the molecular design strategies of dendritic gelators with an emphasis on the discussion of their gelating units and position in molecular structures. Subsequently, we discuss the potential applications of dendritic gels in light harvesting, stimuli responsive materials, sensors and environmental remediation. In addition, the potential challenges and future perspectives of poly(benzyl ether) dendritic gels have also been discussed. It is hoped that this feature article will attract increasing attention and provide some valuable insights for the future design and evolution of supramolecular gels.


Subject(s)
Dendrimers , Dendrimers/chemistry , Ether/chemistry , Gels/chemistry , Molecular Structure , Molecular Weight
13.
Angew Chem Int Ed Engl ; 61(34): e202205739, 2022 Aug 22.
Article in English | MEDLINE | ID: mdl-35766225

ABSTRACT

The enantioselective hydrogenation of arenols to corresponding chiral cyclic alcohols remains a challenge because of their aromaticity and the difficulty in controlling the regio-, chemo-, and stereoselectivity. In this work, the first highly efficient ruthenium-catalyzed enantioselective hydrogenation of 9-phenanthrols has been successfully realized under mild conditions via trapping the unstable keto tautomers. The method provides a facile access to a range of chiral 9,10-dihydrophenanthren-9-ols with up to 98 % yield and >99 % ee. The hydrogenation pathway includes base-promoted tautomerization of 9-phenanthrols and Ru-catalyzed asymmetric hydrogenation of the in situ generated unstable keto tautomers.

14.
Angew Chem Int Ed Engl ; 61(26): e202202972, 2022 Jun 27.
Article in English | MEDLINE | ID: mdl-35438237

ABSTRACT

A unique family of chiral peraza N6 -macrocyclic ligands, which are conformationally rigid and have a tunable saddle-shaped cavity, is described. Utilizing their manganese(I) complexes, the first example of earth-abundant transition metal-catalyzed asymmetric formal anti-Markovnikov hydroamination of allylic alcohols was realized, providing a practical access to synthetically important chiral γ-amino alcohols in excellent yields and enantioselectivities (up to 99 % yield and 98 % ee). The single-crystal structure of a MnI complex indicates that the manganese atom coordinates with the chiral dialkylamine moiety in a bidentate fashion. Further DFT calculations revealed that five of the six nitrogen atoms in the ligand were engaged in multiple noncovalent interactions with Mn, an isopropanol molecule, and a ß-amino ketone intermediate via coordination, hydrogen bonding, and/or CH⋅⋅⋅π interactions in the transition state, showing a remarkable role of the macrocyclic framework.

15.
Dalton Trans ; 51(12): 4644-4652, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35212335

ABSTRACT

Metal vanadates have been popularly advocated as promising anode materials for lithium-ion batteries (LIBs) benefiting from their high theoretical specific capacity and abundant resources. Given that manganese and vanadium are reasonably economical elements and enjoy assorted redox reactions, they have extensive application prospects in energy storage systems. Here, we synthesized cubic MnV2O4 as an anode for LIBs by an efficient sol-gel process. As a result, the MnV2O4 electrode delivers distinguished electrochemical performance, including an appealing reversible specific capacity of nearly 1325 mA h g-1 for 500 cycles at 200 mA g-1, excellent cycling stability with a capacity of 399 mA h g-1 up to 500 cycles at 2000 mA g-1 and a favorable rate capability of 516/410 mA h g-1 at 1000/2000 mA g-1 (when the current density recuperates to 200 mA g-1, the specific capacity still boosts as the number of cycles increases). What's more, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) under various scan rates and scanning electron microscopy (SEM) are executed to ascertain with a greater depth the electrochemical kinetic characteristics and morphology of the MnV2O4 electrode in different states. These results make known that MnV2O4 is a credible anode material for LIBs, and such a facile and economical synthetic route can be extended to the preparation of other metal vanadate materials.

16.
Angew Chem Int Ed Engl ; 61(15): e202200638, 2022 Apr 04.
Article in English | MEDLINE | ID: mdl-35104023

ABSTRACT

A novel pH-responsive molecular shuttle based on a [2]rotaxane with a phosphine ligand has been designed and synthesized. In the rhodium-catalyzed hydrogenation of α,ß-dehydroamino acid esters and aryl enamides, ON/OFF-switchable catalysis was accomplished with high ON/OFF ratios by adjusting the movements of the rotaxane wheels located at the catalyst terminals with acid/base. Mechanistic studies using NMR spectroscopy and quasi in situ X-ray photoelectron spectroscopy revealed that RhIII -hydride species are possibly formed in a H2 atmosphere when the catalyst is in the OFF state. During the reaction, a heterolytic activation of dihydrogen occurs by the interlocked rotaxane dibenzylamine and RhI catalytic center acting as a frustrated Lewis pair. Subsequent homolytic splitting of dihydrogen with the newly formed RhI -hydride species generates RhIII -hydride species. These findings show that a substrate-selective hydrogenation can be achieved by using the OFF-state catalyst.

17.
Dalton Trans ; 51(10): 4173-4181, 2022 Mar 08.
Article in English | MEDLINE | ID: mdl-35188520

ABSTRACT

A series of Fe-doped Na3Mn2-xFex(P2O7)(PO4) (x = 0, 0.2, 0.4) (abbreviated as NMFP-0/NMFP-0.2/NMFP-0.4) compounds have been successfully prepared using the sol-gel method. The Rietveld refinement results indicate that single-phase Na3Mn2-xFex(P2O7)(PO4) with an orthorhombic structure can be obtained. Our results reveal that by controlling the raw materials, the molar ratio of the reactants, the stirring rate of the precursor, the annealing temperature rate, and the reaction time, the proportion of nanowires in the morphology increases as the Fe component rises, and the NMFP-0.4 nanowire-shaped compounds show the best electrochemical activity when used as a cathode material for SIBs. Additionally, its specific capacity is enhanced to ∼126 mA h g-1 in the first cycle when operated at 0.1 C and a working potential window of 1.8-4.3 V (vs. Na/Na+). The material can also be applied in lithium-ion batteries as an anode and achieves ∼600 mA h g-1 specific capacity at a current density of 0.1 C (1 C = 1000 mA g-1) in a working potential window of 0.01-3 V (vs. Li/Li+).

18.
Dalton Trans ; 50(33): 11568-11578, 2021 Sep 07.
Article in English | MEDLINE | ID: mdl-34351346

ABSTRACT

Transition metal oxides (TMOs) are prospective anode materials for lithium-ion batteries (LIBs), owing to their high theoretical specific capacity. However, the inherently low conductivity of TMOs restricts their application. The coupling of lithium-ion conducting polymer ligands with TMO structures is favorable for the dynamics of electrochemical processes. Herein, vanadyl acetate (VA) nanobelts, an organic-inorganic hybrid material, are synthesized for the first time as an anode material for LIBs. As a result, the VA nanobelt electrode displays an outstanding electrochemical performance, including a highly stable reversible specific capacity (around 1065 mA h g-1 at 200 mA g-1), superior long-term cyclability (with a capacity of approximately 477 mA h g-1 at 2 A g-1 over 500 cycles) and attractive rate capability (1012 mA h g-1 when the current density recovers to 200 mA g-1). In addition, scanning electron microscopy (SEM), cyclic voltammetry (CV) curves at different scanning rates and electrochemical impedance spectroscopy (EIS) are used to investigate the variation of the specific capacity and the electrochemical kinetic characteristics of the VA electrode during cycling in detail, respectively. Also, the structural variations of the VA electrode in the initial two cycles are also investigated by in situ XRD testing. The periodic evolution of the in situ XRD patterns demonstrates that the VA nanobelt electrode shows excellent reversibility for Li+ ion insertion/extraction. This work offers an enlightening insight into the future research into organo-vanadyl hybrids as advanced anode materials.

19.
J Org Chem ; 86(13): 8695-8705, 2021 Jul 02.
Article in English | MEDLINE | ID: mdl-34124915

ABSTRACT

1,3-Dipolar cycloaddition of azomethine ylides and electron deficient alkenes is widely studied for rapid installation of pyrrolidine frameworks. Despite significant advances, the major limitations of this process are creating chiral pyrrolidines bearing a quaternary stereogenic center and controlling the diastereoselectivity. Herein, we present an exo-selective asymmetric 1,3-dipolar cycloaddition to access chiral pyrrolidines with four contiguous stereogenic centers, including a fluorinated quaternary stereogenic center at C4, wherein a Cu(OAc)2/(S)-tol-BINAP catalyst and α-fluoro-α,ß-unsaturated arylketone dipolarophiles are used. Epimerization promoted by 5.0 equiv of DBU at 90 °C results in the formation of chiral 4-fluoropyrrolidines (exo') while maintaining the optical purity.

20.
Dalton Trans ; 50(21): 7293-7304, 2021 Jun 01.
Article in English | MEDLINE | ID: mdl-33955440

ABSTRACT

The single-phase binary nickel vanadate Ni2V2O7 was successfully synthesized by a simple solid-state method to explore novel anode materials for lithium-ion batteries. After an activation process, the Ni2V2O7 electrode exhibited excellent electrochemical performance with a stable, high specific capacity of about 960 mA h g-1 at a current density of 100 mA g-1, which is attributed to the multiple valence states and the synergistic effect of the transition elements V and Ni. Even at a high current density of 2000 mA g-1, a stable specific capacity of about 400 mA h g-1 was still obtained. Considering the influence of the activation process on the electrochemical performance of the Ni2V2O7 electrode, we studied the origin of the excellent electrochemical performance, where the improved lithium diffusion coefficient and increased pseudocapacitive contribution caused by the activation process led to a significant improvement in the electrochemical performance, including rate capacity and cycle stability. By combining in situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectroscopy (XPS) methods, for the first time, we illustrate the detailed lithium storage mechanism of the Ni2V2O7 electrode during the lithium insertion/extraction process.

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