Optimizing charge transfer and alleviating volume expansion in electrode materials are critical to maximize electrochemical performance for energy storage systems. Herein, an atomically thin ...soft-rigid Co
S
@MoS
core-shell heterostructure with dual cation vacancies at the atomic interface is constructed as a promising anode for high-performance sodium-ion batteries. The dual cation vacancies involving V
and V
in the heterostructure and the soft MoS
shell afford ionic pathways for rapid charge transfer, as well as the rigid Co
S
core acts as the dominant active component and resists structural deformation during charge/discharge. Electrochemical testing and theoretical calculations demonstrate both excellent Na
transfer kinetics and pseudocapacitive behavior. Consequently, the soft-rigid heterostructure delivers extraordinary sodium storage performance (389.7 mA h g
after 500 cycles at 5.0 A g
), superior to those of the single-phase counterparts; and the assembled Na
V
(PO
)
||d-Co
S
@MoS
/S-Gr full cell achieves an energy density of 235.5 Wh kg
at 0.5 C. Our finding opens up a new strategy of soft-rigid heterostructure and broadens the horizons of material design in energy storage and conversion. This article is protected by copyright. All rights reserved.
Considering the ever‐growing climatic degeneration, sustainable and renewable energy sources are needed to be effectively integrated into the grid through large‐scale electrochemical energy storage ...and conversion (EESC) technologies. With regard to their competent benefit in cost and sustainable supply of resource, room‐temperature sodium‐ion batteries (SIBs) have shown great promise in EESC, triumphing over other battery systems on the market. As one of the most fascinating cathode materials due to the simple synthesis process, large specific capacity, and high ionic conductivity, Na‐based layered transition metal oxide cathodes commonly suffer from the sluggish kinetics, multiphase evolution, poor air stability, and insufficient comprehensive performance, restricting their commercialization application. Here, this review summarizes the recent advances in layered oxide cathode materials for SIBs through different optimal structure modulation technologies, with an emphasis placed on strategies to boost Na+ kinetics and reduce the irreversible phase transition as well as enhance the store stability. Meanwhile, a thorough and in‐depth systematical investigation of the structure–function–property relationship is also discussed, and the challenges as well as opportunities for practical application electrode materials are sketched. The insights brought forward in this review can be considered as a guide for SIBs in next‐generation EESC.
The recent research progress of structure modulation technology on layered transition metal oxide cathodes for sodium‐ion batteries is summarized, concentrating especially on morphology design, coating technology, phase transition, ordering‐disordering, air stability, and composite structure to boost Na+ kinetics, suppress the irreversible phase transition, enhance the storage stability, improve the overall performance, and further realize sodium‐ion battery commercialization for market applications.
It is still very urgent and challenging to simultaneously develop high‐rate and long‐cycle oxide cathodes for sodium‐ion batteries (SIBs) because of the sluggish kinetics and complex multiphase ...evolution during cycling. Here, the concept of accurately manipulating structural evolution and formulating high‐performance heterostructured biphasic layered oxide cathodes by local chemistry and orbital hybridization modulation is reported. The P2‐structure stoichiometric composition of the cathode material shows a layered P2‐ and O3‐type heterostructure that is explicitly evidenced by various macroscale and atomic‐scale techniques. Surprisingly, the heterostructured cathode displays excellent rate performance, remarkable cycling stability (capacity retention of 82.16% after 600 cycles at 2 C), and outstanding compatibility with hard carbon anode because of the integrated advantages of intergrowth structure and local environment regulation. Meanwhile, the formation process from precursors during calcination and the highly reversible dynamic structural evolution during the Na+ intercalation/deintercalation process are clearly articulated by a series of in situ characterization techniques. Also, the intrinsic structural properties and corresponding electrochemical behavior are further elucidated by the density of states and electron localization function of density functional theory calculations. Overall, this strategy, which finely tunes the local chemistry and orbitals hybridization for high‐performance SIBs, will open up a new field for other materials.
An abnormal heterostructured biphasic layered oxide cathode for sodium‐ion batteries (SIBs) is successfully constructed, and its dynamic formation process, intrinsic structural properties, and electrochemical behavior are elucidated by a series of in situ characterization techniques and density functional theory calculations. The concept of accurately manipulating structural evolution and formulating heterostructured cathode materials by local chemistry and orbital hybridization modulation is further demonstrated.
Layered oxides have become the research focus of cathode materials for sodium‐ion batteries (SIBs) due to the low cost, simple synthesis process, and high specific capacity. However, the poor air ...stability, unstable phase structure under high voltage, and slow anionic redox kinetics hinder their commercial application. In recent years, the concept of manipulating orbital hybridization has been proposed to simultaneously regulate the microelectronic structure and modify the surface chemistry environment intrinsically. In this review, the hybridization modes between atoms in 3d/4d transition metal (TM) orbitals and O 2p orbitals near the region of the Fermi energy level (EF) are summarized based on orbital hybridization theory and first‐principles calculations as well as various sophisticated characterizations. Furthermore, the underlying mechanisms are explored from macro‐scale to micro‐scale, including enhancing air stability, modulating high working voltage, and stabilizing anionic redox chemistry. Meanwhile, the origin, formation conditions, and different types of orbital hybridization, as well as its application in layered oxide cathodes are presented, which provide insights into the design and preparation of cathode materials. Ultimately, the main challenges in the development of orbital hybridization and its potential for the production application are also discussed, pointing out the route for high‐performance practical sodium layered oxide cathodes.
Based on orbital hybridization theory, the challenges of layered oxide cathodes in terms of air stability, high voltage, anion redox chemistry, and improving the intrinsic characteristics through interactions between the 3d/4d transition metal and the O 2p atomic orbitals are summarized. This strategy of modulating orbitals hybridization will promote the development of sodium layered oxide cathodes and its commercialization process.
Parkinson's disease (PD) is a neurodegenerative disorder with no absolute cure. The evidence of the involvement of gut microbiota in PD pathogenesis suggests the need to identify certain molecule(s) ...derived from the gut microbiota, which has the potential to manage PD. Osteocalcin (OCN), an osteoblast-secreted protein, has been shown to modulate brain function. Thus, it is of interest to investigate whether OCN could exert protective effect on PD and, if yes, whether the underlying mechanism lies in the subsequent changes in gut microbiota.
The intraperitoneal injection of OCN can effectively ameliorate the motor deficits and dopaminergic neuronal loss in a 6-hydroxydopamine-induced PD mouse model. The further antibiotics treatment and fecal microbiota transplantation experiments confirmed that the gut microbiota was required for OCN-induced protection in PD mice. OCN elevated Bacteroidetes and depleted Firmicutes phyla in the gut microbiota of PD mice with elevated potential of microbial propionate production and was confirmed by fecal propionate levels. Two months of orally administered propionate successfully rescued motor deficits and dopaminergic neuronal loss in PD mice. Furthermore, AR420626, the agonist of FFAR3, which is the receptor of propionate, mimicked the neuroprotective effects of propionate and the ablation of enteric neurons blocked the prevention of dopaminergic neuronal loss by propionate in PD mice.
Together, our results demonstrate that OCN ameliorates motor deficits and dopaminergic neuronal loss in PD mice, modulating gut microbiome and increasing propionate level might be an underlying mechanism responsible for the neuroprotective effects of OCN on PD, and the FFAR3, expressed in enteric nervous system, might be the main action site of propionate. Video abstract.
Sodium‐ion oxide cathodes with triphase heterostructures have attracted intensive attention, since the sodium‐storage performance can be enhanced by utilizing the synergistic effect of different ...phases. However, the composite structures generally suffer from multiple irreversible phase transitions and high lattice strain because of interlayer‐gliding during the charge/discharge process. Here, the concept of strain engineering via manipulating the local chemistry of heterostructured oxide cathode is proposed to regulate the relevant physical and chemical properties, resulting in highly reversible structural evolution (P2/P3/spinel → P2/P3″/spinel) and low intrinsic stress in the potential window of 1.5–4.0 V. Also, the simple structural evolution at a relatively high cut‐off potential of 4.3 V can be detected by in situ X‐ray diffraction and other electrochemical characterization techniques during Na+ extraction/insertion. Meanwhile, the electrode exhibits a high reversible capacity (169.4 mAh g−1 at 0.2 C) and excellent rate performance from 1.5 to 4.3 V. Overall, this study reveals the mechanisms of regulating local chemistry to realize strain engineering of the cathode materials and paves the way for the further improvement of high‐performance sodium‐ion batteries.
Strain engineering by manipulating the local chemistry of a heterostructured oxide cathode can facilitate phase transformation and suppress lattice strain, resulting in high‐performance sodium‐ion batteries. The concept of local chemistry modulation can also be used to regulate the physical and chemical properties of other electrode materials and further inspire the exploitation of new materials and chemistries in energy storage and conversion.
Salvia miltiorrhiza is a model plant for Chinese herbal medicine with significant pharmacologic effects due to its tanshinone components. Our previous study indicated that nitrogen starvation stress ...increased its tanshinone content. However, the molecular mechanism of this low nitrogen-induced tanshinone biosynthesis is still unclear. Thus, this study aimed to elucidate the molecular mechanism of tanshinone biosynthesis in S. miltiorrhiza under different N conditions N-free (N0), low-N (Nl), and full-N (Nf, as control) conditions by using transcriptome and metabolome analyses. Our results showed 3,437 and 2,274 differentially expressed unigenes between N0 and Nf as well as Nl and Nf root samples, respectively. N starvation (N0 and Nl) promoted the expression of the genes involved in the MVA and MEP pathway of tanshinone and terpenoid backbone biosynthesis. Gene ontology and KEGG analyses revealed that terpenoid backbone biosynthesis, hormone signal transduction, and phenylpropanoid biosynthesis were promoted under N starvation conditions, whereas starch and sucrose metabolisms, nitrogen and phosphorus metabolisms, as well as membrane development were inhibited. Furthermore, metabolome analysis showed that metabolite compounds and biosynthesis of secondary metabolites were upregulated. This study provided a novel insight into the molecular mechanisms of tanshinone production in S. miltiorrhiza in response to nitrogen stress.
Many strategies have been developed for constructing anisotropic hydrogels, however, it remains a challenge to fabricate hydrogels with anisotropic nanocrystalline domains from intrinsically soft ...networks. Here, we report a naphthotube‐based polyrotaxane‐containing hydrogel that can be reinforced via mechanical training. During the training process, the hydrogel can adopt reorientation of polymer chains to form anisotropic structures driven by external uniaxial force. Due to the multiple hydrogen bonding sites and movable feature of naphthotube, the sliding of naphthotube on PEG chains simultaneously inducing the zipping of adjacent polymer chains to form densely anisotropic nanocrystalline domains through hydrogen bonded networks. Thus, the trained hydrogel exhibits an enhanced tension stress of ≈110 kPa, which realize a remarkable enhancement of ≈10 times compare to initial state. This study provides a new tactic for improving the mechanical performance of soft materials.
A naphthotube‐based polyrotaxane‐containing hydrogel was constructed through one‐pot photo‐initiated copolymerization. Naphthotube can slide along the PEG chain upon repeated stretching. The slide motion further induces the zipping of adjacent polymer chains to form compact hydrogen bonded nanocrystalline domains through integrated hydrogen bonds, which enabled the hydrogel to achieve reinforcement.
Immunity deteriorates with age in animals but comparatively little is known about the temporal regulation of plant resistance to herbivores. The phytohormone jasmonate (JA) is a key regulator of ...plant insect defense. Here, we show that the JA response decays progressively in Arabidopsis. We show that this decay is regulated by the miR156-targeted SQUAMOSA PROMOTER BINDING PROTEIN-LIKE9 (SPL9) group of proteins, which can interact with JA ZIM-domain (JAZ) proteins, including JAZ3. As SPL9 levels gradually increase, JAZ3 accumulates and the JA response is attenuated. We provide evidence that this pathway contributes to insect resistance in young plants. Interestingly however, despite the decay in JA response, older plants are still comparatively more resistant to both the lepidopteran generalist Helicoverpa armigera and the specialist Plutella xylostella, along with increased accumulation of glucosinolates. We propose a model whereby constitutive accumulation of defense compounds plays a role in compensating for age-related JA-response attenuation during plant maturation.
Layered transition metal oxide (NaxTMO2), being one of the most promising cathode candidates for sodium‐ion batteries (SIBs), have attracted intensive interest because of their nontoxicity, high ...theoretical capacities, and easy manufacturability. However, their physical and electrochemical properties of water sensitivity, sluggish Na+ transport kinetics, and irreversible multiple‐phase translations hinder the practical application. Here, a concept of surface lattice‐matched engineering is proposed based on in situ spinel interfacial reconstruction to design a spinel coating P2/P3 heterostructure cathode material with enhanced air stability, rate, and cycle performance. The novel structure and its formation process are verified by transmission electron microscopy and in situ high‐temperature X‐ray diffraction. The electrode exhibits an excellent rate performance with the highly reversible phase transformation demonstrated by in situ charging/discharging X‐ray diffraction. Additionally, even after a rigorous water sensitivity test, the electrode materials still retain almost the same superior electrochemical performance as the fresh sample. The results show that the surface spinel phase can play a vital role in preventing the ingress of water molecules, improving transport kinetics, and enhancing structural integrity for NaxTMO2 cathodes. The concept of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction will be helpful for designing new ultra‐stable cathode materials for high‐performance SIBs.
The formation process and function mechanism for inhibiting phase transformation and enhancing air stability of surface lattice‐matched engineering based on in situ spinel interfacial reconstruction are studied. This strategy of designing heterostructure with in situ interfacial reconstruction will inspire the exploitation of new chemistries and materials.
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