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Recently, the Ni-rich layered LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) is established as a promising cathode material for next-generation lithium-ion batteries (LIBs). However, it always suffers from severe bulk structural and interfacial degradation during electrochemical operation. To well address the issues, herein, a three-in-one engineering strategy is devised to construct a stable Nb-doped full concentration-gradient NCM811 coated with rhombohedral LiNbO 3 (denoted as N-FCG-NCM811@LNO). In the strategy, each secondary particle possesses a Ni-rich core and a Co/Mn-rich outer surface, along with the Li+-conductive LNO coating layer and surface gradient Nb doping. It is the synergistic contributions from three-aspect design (i.e. , FCG construction, surface coating and heteroatom doping) that renders NCM811 cathodes with stable crystalline structure and surface, mitigated microcracks, accelerated Li+ diffusion kinetic, and suppressed interfacial phase transition over cycling. The optimum N-FCG-NCM811@LNO achieves the improved capacity retention at high cut-off voltages (∼85.1% after 300 cycles between 3.0 and 4.4 V, and ∼80.5% after 200 cycles between 3.0 and 4.5 V both at 1C rate) and better high-rate capability (∼162.4 mAh g−1 at 10C). More meaningfully, the instructive electrode design concept here can be extended to other Ni-rich cathodes for high-energy/power LIBs via the simple yet scalable fabrication process. • A three-in-one engineering strategy is devised to construct N-FCG-NCM811@LNO. • The FCG design accommodates anisotropic internal strain and ensures bulk stability. • LNO coating favors Li + diffusion kinetic and minimizes surf-/interfacial decay. • Nb doping reduces cation mixing degree/phase transitions and microcracks in cycles. • The optimum cathode achieves superb high-rate capability and capacity retention. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mesoporous NiCo-MOF microspheres are fabricated via solvothermal method. • Polyvinylpyrrolidone is a structure-directing agent in formation of microspheres. • NiCo-MOF owns high structure stability/crystallinity and rich electroactive sites. • Carboxylate and benzene ring moieties favor for efficient Li storage. • The NiCo-MOF based LICs display high energy density and superb cyling stability. Rational design of appropriate negative electrode materials with high rates and long cycle life is essential to construct advanced lithium-ion capacitors (LICs). Herein, we solvothermally synthesize the bimetallic (Ni, Co) organic framework (NiCo-MOF) microspheres by using the polyvinylpyrrolidone as a structure-directing agent towards advanced LICs as a battery-type negative electrode. Benefiting from its rigid structure stability, high crystallinity, rich electroactive sites and high-content mesopores, the NiCo-MOF electrode obtains a large reversible capacity of ~557.1 mAh g−1 at 0.1 A g−1. Furthermore, the NiCo-MOF based LICs display a high SC of ~58.2 F g−1 at ~1.0 A g−1, along with an exceptional capacitance retention over 8500 cycles at 1.0 A g−1. More significantly, the contribution here will stimulate extensive development of versatile MOF microspheres for next-generation LICs and beyond. [ABSTRACT FROM AUTHOR]

Micro-/mesoporous carbon sub-microspheres are fabricated via eco-friendly and scalable synthesis strategy, and exhibit attractive electrochemical properties for supercapacitors and sodium-ion batteries as competitive electrodes. • MCMS-K is scalably synthesized for supercapacitors and sodium-ion batteries. • Starch and KHCO 3 are favorable for commercial applications. • MCMS-K exhibits higher capacitance thanks to the surface oxygen functional groups. • MCMS-K delivers attractive supercapacitances in aqueous and organic electrolytes. • MCMS-K renders the Na+ ads-/desorption dominated Na+-storage process. Cost-efficiency utilization of carbon sub-microspheres is greatly significant for their versatile energy-related applications. However, eco-friendly synthesis and moderate activation protocols for enhancing their electrochemical performances are still challenging. Herein, we explore a facile two-step methodology, i.e. , hydrothermal carbonization and subsequent mild activation, for bottom-up fabrication of KHCO 3 activated micro-/mesoporous carbon microspheres (MCMS-K) as competitive electrodes towards electrochemical capacitors (ECs) and sodium-ion batteries (SIBs) by using the soluble starch as a low-cost precursor. Benefitting from its high specific surface area (~1972.8 m2 g−1), abundant micropores (~88.8%), and high graphitization degree, the MCMS-K electrode obtains a specific capacitance of ~369.8 F g−1 (~266.3 F cm−3) at 1 A g−1 in 1 M H 2 SO 4 , higher than that in 6 M KOH, thanks to the surface oxygen functional groups involved pseudocapacitance. More remarkably, the MCMS-K based organic symmetrical ECs deliver a high-rate energy density of 34.4 Wh kg−1 at 12.5 kW kg−1, and ultra-long cycling stability. Besides, the MCMS-K anode renders a high-rate capacity of ~78.6 F g−1 at 5.0 A g−1 via Na+ surface adsorption and intercalation accompanying with excellent cycling behaviors for SIBs. It strongly highlights the promising applications of our MCMS-K product in ECs and SIBs. [ABSTRACT FROM AUTHOR]

Recently, the Ni-rich LiNi 0·8 Co 0·1 Mn 0·1 O 2 (NCM811) cathode with high-energy applications has received tremendous interest for Li-ion batteries (LIBs). But it still suffers from serious capacity degradation upon cycling owing to the involved sur-/interface issues. In the work, we first propose an efficient surface modification strategy to in-situ fabricate the NCM811 coated with solid electrolyte Li 3 PO 4 , and systematically investigate the effect of Li 3 PO 4 nano coating layer on electrochemical stability of the NCM811 for LIBs as competitive cathodes. It is the smart surface coating of Li+ conductive Li 3 PO 4 that lowers the sensitivity to H 2 O and CO 2 , relieves the evolution of strain-induced intergranular micro-cracks, slows the HF corrosion, and retains the fast Li+ diffusion coefficients with appropriate coating content. The optimized NCM811@Li 3 PO 4 cathode yields the remarkable electrochemical Li-storage properties in terms of reversible capacities, capacity retention and rate behaviors. More competitively, the NCM811@Li 3 PO 4 based pouch-type devices deliver a cell-level energy density of ∼304.6 Wh kg−1, along with a capacity retention of 89.6% over 250 cycles at 1.0 C. The appealing features highlight promising application of the resultant NCM811@Li 3 PO 4 cathodes in next-generation LIBs. The core-shell NCM811@Li 3 PO 4 cathode was in-situ constructed, optimized and exhibited remarkable Li-storage properties towards high-energy-density lithium ion batteries as promisingly commercial cathodes. Image 1 • An efficient in-situ surface modification strategy is explored for coating NCM811 with solid electrolyte Li 3 PO 4. • The surface coating of Li+-conductive Li 3 PO 4 lowers the sensitivity to H 2 O and CO 2 of NCM811. • The nano Li 3 PO 4 coating relieves the evolution of intergranular micro-cracks and slows the HF corrosion. • The optimal NCM811@Li 3 PO 4 cathode yields the remarkable electrochemical Li-storage properties. • The NCM811@Li 3 PO 4 based pouch-type device shows large energy density and appealing capacity retention. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) have recently gained extensive attention due to their high energy density, low cost, and environmental friendliness. However, serious shuttle effect and uncontrolled growth of lithium dendrites restrict them from further commercial applications. As "the third electrode", functional separators are of equal significance as both anodes and cathodes in LSBs. The challenges mentioned above are effectively addressed with rational design and optimization in separators, thereby enhancing their reversible capacities and cycle stability. The review discusses the status/operation mechanism of functional separators, then primarily focuses on recent research progress in versatile separators with purposeful modifications for LSBs, and summarizes the methods and characteristics of separator modification, including heterojunction engineering, single atoms, quantum dots, and defect engineering. From the perspective of the anodes, distinct methods to inhibit the growth of lithium dendrites by modifying the separator are discussed. Modifying the separators with flame retardant materials or choosing a solid electrolyte is expected to improve the safety of LSBs. Besides, in-situ techniques and theoretical simulation calculations are proposed to advance LSBs. Finally, future challenges and prospects of separator modifications for next-generation LSBs are highlighted. We believe that the review will be enormously essential to the practical development of advanced LSBs., (© 2024 Wiley-VCH GmbH.)

Nanowhisker-like Cu 3 (HHTP) 2 composed of neat arrays grown on a copper foam is rationally designed and prepared using Cu(OH) 2 nanowire arrays as a self-sacrifice template. Benefiting from the good conductivity of Cu 3 (HHTP) 2 and an ordered array structure, the optimized Cu 3 (HHTP) 2 @CF-3 electrode exhibits high area capacity, good rate performance and cyclic stability.

The development of advanced layered Ni-rich cathodes is essential for high-energy lithium-ion batteries (LIBs). However, the prevalent Ni-rich cathodes are still plagued by inherent issues of chemomechanical and thermal instabilities and limited cycle life. For this, here, we introduce an efficient approach combining single-crystalline (SC) design with in situ high-entropy (HE) doping to engineer an ultrahigh-Ni cobalt-free layered cathode of LiNi 0.88 Mn 0.03 Mg 0.02 Fe 0.02 Ti 0.02 Mo 0.02 Nb 0.01 O 2 (denoted as HE-SC-N88). Thanks to the SC- and HE-doping merits, HE-SC-N88 is featured with a grain-boundary-free and stabilized structure with minimal lattice strain, preventing mechanical degradation, reducing surface parasitic reactions, and mitigating oxygen loss. Accordingly, our HE-SC-N88 cathode demonstrates exceptional electrochemical properties particularly with prolonged cycling stability under strenuous conditions in both half and full cells, and the delayed O loss-induced phase transitions upon heating. More meaningfully, our design of HE doping in redefining the ultrahigh-Ni Co-free SC cathodes will make a tremendous progress toward industrial application of next-generation LIBs.

Sodium ion capacitors (SICs) that combine the merits of both rechargeable batteries and supercapacitors have gained widespread recognition for their high energy density and extended cycle life as new energy storage devices. However, the purposeful design of advanced battery-type anodes has become an urgent need to remedy the dynamics mismatch with the capacitive cathode. Herein, we propose a simple but efficient bottom-up approach to build three-dimensional Mo 2 C/C hybrid architectures in situ as anodes for SICs. By finely regulating the ratio of carbon and molybdenum sources, the optimized Mo 2 C/C, where even thinner subunit assembled Mo 2 C nanodisk (∼47.1 nm in thickness) arrays are immobilized on carbon nanosheet substrate via the synchronous embedded growth, rapid electron and ion diffusion/transport expressways, abundant active sites and robust structural stability were achieved for efficient sodium storage. Benefiting from the synergistic contributions of the components, the optimum Mo 2 C/C anode displays an outstanding rate and long-cycle properties as a competitive anode. Moreover, the constructed Mo 2 C/C-based SICs exhibited an energy density of ∼16.7 W h kg -1 at 10 kW h kg -1 , along with ∼22.5% capacitance degradation over 4000 cycles at 1 A g -1 . This contribution will guide the precise synthesis of other versatile Mo 2 C-based hybrids towards energy-related applications and beyond.

The practical application of metalloid black phosphorus (BP) based anodes for potassium ion batteries is mainly impeded by its instability in air and irreversible/sluggish potassium storage behaviors. Herein, a 2D composite is purposefully conceptualized, where ultrathin BP nanodisks with Fe 3 O 4 nanoclusters are hybridized with Lewis acid iron (V)-oxo complex (FC) nanosheets (denoted as BP@Fe 3 O 4 -NCs@FC). The introduced electron coordinate bridge between FC and BP, and hydrophobic surface of FC synergistically assure that BP@Fe 3 O 4 -NCs@FC is ultrastable in humid air. With the purposeful structural and componential design, the resultant BP@Fe 3 O 4 -NCs@FC anode is endowed with appealing electrochemical performance in terms of reversible capacity, rate behavior, and long-duration cycling stability in both half and full cells. Furthermore, the underlying formation and potassium-storage mechanisms of BP@Fe 3 O 4 -NCs@FC are tentatively proposed. The in-depth insights here will provide a crucial understanding in rational exploration of advanced anodes for next-generation PIBs., (© 2023 Wiley-VCH GmbH.)

To alleviate the restacking issue of 2D Ti 3 C 2 T x itself, we purposefully explore a simple but efficient method for controllable construction of 1D Ti 3 C 2 T x nanoscrolls with a high efficiency of ∼90.5%, with detailed regulation of the feed concentrations and surface energy of Ti 3 C 2 T x . The involved transformation mechanism from 2D nanosheets to 1D nanoscrolls is reasonably proposed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Recently, Li-ion capacitors (LICs) have drawn tremendous attention due to their high energy/power density along with long cycle life. Nevertheless, the slow kinetics and stability of the involved anodes as bottleneck barriers always result in the modest properties of devices. The exploration of advanced anodes with both high ionic and electronic conductivities as well as structural stability thus becomes more significant for practical applications of LICs. Herein, a single-crystal nano-subunits assembled hierarchical accordion-shape WNb 2 O 8 micro-/nano framework is first designed via a one-step scalable strategy with the multi-layered Nb 2 CT x as a precursor. The underlying solid solution Li-storage mechanism of the WNb 2 O 8 just with a volumetric expansion of ≈1.5% is proposed with in situ analysis. Benefiting from congenitally crystallographic merits, single-crystalline characteristic, and open accordion-like architecture, the resultant WNb 2 O 8 as a robust anode platform is endowed with fast electron/ion transport capability and multi-electron redox contributions from W/Nb, and accordingly, delivers a reversible capacity of ≈135.5 mAh g -1 at a high rate of 2.0 A g -1 . The WNb 2 O 8 assembled LICs exhibit an energy density of ≈33.0 Wh kg -1 at 9 kW kg -1 , coupled with remarkable electrochemical stability. The work provides meaningful insights into the rational design and construction of advanced bimetallic niobium oxides for next-generation LICs., (© 2022 Wiley-VCH GmbH.)

The spinel NiCo 2 O 4 and rock-salt NiCoO 2 have been well established as attractive electrodes for supercapacitors. However, what is the intrinsic role of the congenital aspect, i.e. , crystal structure and the surface and/or near-surface controlled electrochemical redox behaviors, if the acquired features ( i.e. , morphology, specific surface area, pore structure, and so on) are wholly ignored? Herein, we purposefully elucidated the underlying influences of unique crystal structures of NiCo 2 O 4 and NiCoO 2 on their pseudocapacitance from mechanism analysis through the density function theory based first-principles calculations, along with the experimental validation. Systematic theoretical calculation and analysis revealed that more charge carriers near the Fermi-level, stronger affinity with OH - in the electrolyte, easier deprotonation process, and the site-enriched characteristic for low-index surfaces of NiCoO 2 enable its faster redox reaction kinetics and greater charge transfer, when compared to the spinel NiCo 2 O 4 . The in-depth understanding of crystal structure-property relationship here will guide rational optimization and selection of appropriate electrodes for advanced supercapacitors., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Aqueous non-lithium based rechargeable batteries are emerging as promising energy storage devices thanks to their attractive rate capacities, long-cycle life, high safety, low cost, environmental-friendliness, and easy assembly conditions. However, the aqueous electrolytes with high ionic conductivity are always restricted by their intrinsically narrow electrochemical window. Encouragingly, the highly concentrated "water-in-salt" (WIS) electrolytes can efficiently expand the stable operation window, which brings up a series of aqueous high-voltage rechargeable batteries. In the mini review, we summarize the latest progress and contributions of various aqueous electrolytes for non-lithium (Na + , K + , Zn 2+ , Mg 2+ , and Al 3+ ) based rechargeable batteries, and give a brief exploration of the operating mechanisms of WIS electrolytes in expanding electrochemically stable windows. Challenges and prospects are also proposed for WIS electrolytes toward aqueous non-lithium rechargeable metal ion batteries., (Copyright © 2020 Wang, Meng, Sun, Liu and Hou.)

In this work, hierarchical hollow BiOBr submicrospheres (HBSMs) were successfully prepared via a facile yet efficient solvothermal strategy. Remarkable effects of solvents upon the crystallinities, morphologies, and microstructures of the BiOBr products were systematically investigated, which revealed that the glycerol/isopropanol volumetric ratio played a significant role in the formation of hollow architecture. Accordingly, the underlying formation mechanism of the hollow submicrospheres was tentatively put forward here. Furthermore, the photocatalytic activities of the resulting HBSMs were evaluated in detail with photocatalytic degradation of the organic methyl orange under visible light irradiation. Encouragingly, the as-obtained HBSMs with striking recyclability demonstrated excellent visible-light-responsive photocatalytic performance, which benefits from their large surface area, effective visible light absorption, and unique hollow feature, highlighting their promising commercial application in waste water treatment., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Linrui Hou et al.)

Recently, there has been an urgent need for flexible and low cost rechargeable batteries for the emerging flexible and wearable electronic devices. Herein, MnS nanoparticles embedded in carbon nanowires/reduced graphene oxide (MnS@CNWs/rGO) composite paper were synthesized via a simple yet scalable strategy with Mn based coordination nanowires and graphene oxide as precursors. The combination of multi-dimensional subunits offers not only a robust structure but also abundant pathways for fast electron/ion diffusion. When directly used as a free-standing electrode for sodium ion batteries (SIBs), the ultra-flexible paper anode exhibits excellent mechanical and electrochemical performance, benefitting from the synergistic effects between nano-dimensional MnS encapsulated in CNWs and conductive rGO nanosheets. Remarkably, a high reversible gravimetric/volumetric capacity of ∼560 mA h g -1 /∼362.3 mA h cm -3 is obtained using the self-supported flexible electrode at a current density of 0.1 A g -1 , which is almost 92.4% of the theoretical capacity of MnS. More competitively, the flexible MnS@CNWs/rGO anode exhibits an unprecedented long cycle life with a high reversible capacity of ∼150 mA h g -1 at 1 A g -1 after 10, 000 cycles. This highly favours the promising application of MnS@CNWs/rGO paper in advanced flexible SIBs as an appealing anode.

Ultrathin core-shell V 3 S 4 @C nanosheets assembled into hierarchical nanotubes (V 3 S 4 @C NS-HNTs) are synthesized by a self-template strategy and evaluated as general anodes for alkali-ion batteries. Structural/physicochemical characterizations and DFT calculations bring insights into the intrinsic relationship between crystal structures and electrochemical mechanisms of the V 3 S 4 @C NS-HNTs electrode. The V 3 S 4 @C NS-HNTs are endowed with strong structural rigidness owing to the layered VS 2 subunits and interlayer occupied V atoms, and efficient alkali-ion adsorption/diffusion thanks to the electroactive V 3 S 4 -C interfaces. The resulting V 3 S 4 @C NS-HNTs anode exhibit distinct alkali-ion-dependent charge storage mechanisms and exceptional long-durability cyclic performance in storage of K + , benefiting from synergistic contributions of pseudocapacitive and reversible intercalation/de-intercalation behaviors superior to those of the conversion-reaction-based Li + -/Na + -storage counterparts., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The cost-efficient ZnMnO 3 has attracted increasing attention as a prospective anode candidate for advanced lithium-ion batteries (LIBs) owing to its resourceful abundance, large lithium storage capacity and low operating voltage. However, its practical application is still seriously limited by the modest cycling and rate performances. Herein, a facile design to scalable synthesize unique one-dimensional (1D) mesoporous ZnMnO 3 nanorods (ZMO-NRs) composed of nanoscale particles (≈11 nm) is reported. The 1D mesoporous structure and nanoscale building blocks of the ZMO-NRs effectively promote the transport of ions/electrons, accommodate severe volume changes, and expose more active sites for lithium storage. Benefiting from these appealing structural merits, the obtained ZMO-NRs anode exhibits excellent rate behavior (≈454 mAh g -1 at 2 A g -1 ) and ultra-long term cyclic performance (≈949.7 mAh g -1 even over 500 cycles at 0.5 A g -1 ) for efficient lithium storage. Additionally, the LiNi 0.8 Co 0.1 Mn 0.1 O 2 //ZMO-NRs full cell presents a practical energy density (≈192.2 Wh kg -1 ) and impressive cyclability with approximately 91 % capacity retention over 110 cycles. This highlights that the ZMO-NRs product is a highly promising high-rate and stable electrode candidate towards advanced LIBs in electronic devices and sustainable energy storage applications., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Conductive metal-organic frameworks (MOFs), as a newly emerging multifunctional material, hold enormous promise in electrochemical energy-storage systems owing to their merits including good electronic conductivity, large surface area, appropriate pore structure, and environmental friendliness. In this contribution, a scalable solvothermal strategy was devised for the bottom-up fabrication of 1D Cu-based conductive MOF, that is, Cu 3 (2,3,6,7,10,11-hexahydroxytriphenylene) 2 (Cu-CAT) nanowires (NWs), which were further utilized as a competitive anode for lithium-ion batteries (LIBs). The intrinsic Li storage mechanism of the Cu-CAT electrode was also explored. Benefiting from its structural virtues, the resultant 1D Cu-CAT NWs were endowed with superb Li + diffusion coefficients and electrochemical conductivities and exhibited remarkably high-rate reversible capacities of approximately 631 mAh g -1 at 0.2 A g -1 and even approximately 381 mAh g -1 at 2 A g -1 , along with striking capacity retention of 81 % after 500 cycles at 0.5 A g -1 . In addition, a Cu-CAT NWs-based full cell assembled with LiNi 0.8 Co 0.1 Mn 0.1 O 2 as the cathode displayed a large energy density of approximately 275 Wh kg -1 as well as excellent cycling behavior. These results manifest the promising application of 1D conductive Cu-CAT NWs in advanced LIBs and even other potential versatile energy-related fields., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

1D Ni-MOFs with a hexagonal honeycomb structure, good electronic conductivity and fast Li + kinetic diffusion were hydrothermally prepared, and they exhibited excellent lithium storage performance in terms of high-rate reversible capacity and long-duration cycling behavior as the anode material in lithium ion batteries., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Recently, Ti-based MXenes were expected to compete with graphene and other carbonaceous materials towards Li-ion batteries (LIBs) due to their two-dimensional (2D) open structure, cost efficiency, superior conductivity and low Li + diffusion barrier. However, the relatively moderate capacity and aggregation tendency hamper their practical applications in next-generation LIBs. Herein, we explore for the first time a scalable bottom-up approach to fabricate a series of Co 3 O 4 @single-layer Ti 3 C 2 T x (s-Ti 3 C 2 T x ) hybrids, where numerous homogeneous Co 3 O 4 nanocrystallites (NCs), serving both as a spacer and electroactive phase, are anchored uniformly on the surface of s-Ti 3 C 2 T x nanosheets (NSs) through the Co-O-Ti interfacial bonds. Furthermore, detailed experimental analyses clearly shed light upon the formation mechanism of the hybrid Co 3 O 4 @s-Ti 3 C 2 T x NSs. Thanks to the structural and compositional merits, the 2D Co 3 O 4 @s-Ti 3 C 2 T x NSs even exhibit a remarkable high-rate capacity of ∼223 mA h g -1 at an ultra-high current density of 10 A g -1 , and a long-span cycle life with a high reversible capacity of 550 mA h g -1 at 1 A g -1 after 700 consecutive cycles. Corresponding density functional theory calculation further confirms that the Co-O-Ti interfacial function leads to an even higher pseudocapacitive contribution and faster lithium storage behavior due to the enhanced interfacial electron transfer.

Recently, rock-salt NiCoO 2 (NCO) with desirable electronic conductivity has drawn enormous interest worldwide for energy-related applications. However, the intrinsically sluggish kinetics and electrode aggregation/volumetric change/pulverization during Li-insertion/-extraction processes hugely limit its applications in Li-ion batteries (LIBs). In the contribution, we first devise a bottom-up method for scalable fabrication of the nanodimensional NCO particles encapsulated in porous nitrogen-doped carbon submicrospheres (NCS), which are derived from a bimetal (Ni, Co) metal-organic framework. The porous NCS, as a flexible conductive skeleton, can buffer distinct volume expansion as an efficient buffering phase, restrain agglomeration of nanoscaled NCO, and enhance electronic conductivity and wettability of the electrode. Benefiting from the synergistic functions between the nanodimensional NCO and porous NCS, the obtained NCO@NCS anode (∼74.5 wt % NCO) is endowed with remarkable high-rate reversible capacity (∼403.0 mAh g -1 at 1.0 A g -1 ) and cycling behaviors (∼371.4 mAh g -1 after being cycled for 1000 times at 1.0 A g -1 ) along with a high lithium diffusion coefficient and remarkable pseudocapacitive contribution. Furthermore, the NCO@NCS-based full LIBs exhibit competitive lithium-storage properties in terms of energy density (∼217.0 Wh kg -1 ) and cyclic stability. Furthermore, we believe that the methodology is highly promising in versatile design and construction of binary metal oxide/carbon hybrid anodes for advanced LIBs.

The development of high-rate cathodes particularly with remarkable wide-temperature-tolerance sodium-storage capability plays a significant role in commercial applications of sodium-ion batteries (SIBs). Herein, we devise a scaled-up electrospinning avenue to fabricate nanocrystal-constructed ultralong layered NaCrO 2 nanowires (NWs) toward SIBs as a wide-temperature-operating cathode. The resultant one-dimensional (1D) NaCrO 2 nanoarchitecture is endowed with orientated and shortened electronic/ionic transport and remarkable structural tolerance to stress change over sodiation-desodiation processes. Benefiting from these structural superiorities, the NaCrO 2 NWs are featured with prominent Na + -storage behaviors in the wide-operating-temperature range from -15 to 55 °C. Promisingly, the NaCrO 2 NWs exhibit extraordinary high-rate capacities of ∼108.8 and ∼87.2 mAh g -1 at 10 and 50 C rates at 25 °C, and even 94.6 (55 °C) and ∼60.1 (-15 °C) mAh g -1 at 10 C, along with outstanding cyclic stabilities with capacity retentions of ∼80.6% (-15 °C), 88.4% (25 °C), and ∼86.9% (55 °C). The overall performance of our NaCrO 2 is superior to other reported NaCrO 2 -based cathodes, even with conductive nanocarbon coating. Encouragingly, a competitive energy density of ∼161 Wh kg -1 can be obtained by the NaCrO 2 NWs-based full cell. Therefore, our NaCrO 2 NWs can be highly anticipated as advanced cathode for commercial wide-temperature-tolerance SIBs.

Surface modifications are established well as efficient methodologies to enhance comprehensive Li-storage behaviors of the cathodes and play a significant role in cutting edge innovations toward lithium-ion batteries (LIBs). Herein, we first logically devised a pilot-scale coating strategy to integrate solid-state electrolyte NaTi 2 (PO 4 ) 3 (NTP) and layered LiNi 0.5 Mn 0.3 Co 0.2 O 2 (NMC) for smart construction of core-shell NMC@NTP cathodes. The Nasicon-type NTP nanoshell with exceptional ion conductivity effectively suppressed gradual encroachment and/or loss of electroactive NMC, guaranteed stable phase interfaces, and meanwhile rendered small sur-/interfacial electron/ion-diffusion resistance. By benefiting from immanently promoting contributions of the nano-NTP coating, the as-fabricated core-shell NMC@NTP architectures were competitively endowed with superior high-voltage cyclic stabilities and rate capacities within larger electrochemical window from 3.0 to 4.6 V when utilized as advanced cathodes for advanced LIBs. More meaningfully, the appealing electrode design concept proposed here will exert significant impact upon further constructing other high-voltage Ni-based cathodes for high-energy/power LIBs.

Mesoporous hetero-structures have drawn tremendous attention due to their unprecedented inherent advantages in advanced Li-ion batteries (LIBs). In this study, we developed a facile metal-organic-framework-engaged synthetic methodology for large-scale fabrication of two-dimensional (2D) mesoporous hetero-ZnFe 2 O 4 /ZnO nanosheets (ZFOZ NSs) with homogeneously dispersed hetero-nanodomains of spinel ZnFe 2 O4 and ZnO. When evaluated as a promising anode for LIB applications, the resultant 2D ultrathin mesoporous hetero-ZFOZ NSs exhibited extraordinary electrochemical Li storage performance with long-cycle behavior and large reversible capacities for next-generation LIB applications, thanks to the attractive synergetic contributions from ultrathin mesoporous architecture and electroactive bi-component hetero-interfaces at the nanoscale. Even more encouragingly, the electrode concept we developed here can be easily generalized to rational design and synthesis of other mesoporous hetero-hybrids with remarkable lithium storage capacities for LIBs.

An efficient anion-exchange protocol was investigated for the controllable fabrication of hollow NiCo 2 S 4 nanoboxes (NBs) from mesocrystalline nickel cobalt carbonate nanocubes as promising pseudocapacitive materials for electrochemical capacitors. The underlying processes of the formation of the hollow architecture were systematically investigated. Originating from the unique structural and compositional advantages, the resultant hollow NiCo 2 S 4 NB electrode with a loading of 5 mg cm 2 delivered a large specific capacitance of 777 F g -1 at a high rate of 4 A g -1 in a three-electrode configuration with 6 m KOH as electrolyte. Furthermore, an asymmetric device constructed with the hollow NBs and activated carbon (AC) as positive and negative electrodes, respectively, showed extraordinary supercapacitance within an electrochemically operating voltage window from 0.0 to 1.5 V. The unique AC//NiCo 2 S 4 NB hybrid capacitor exhibited a large specific energy density (active mass normalized) of approximately 17.1 W h kg -1 at a high power density of 2250 W kg -1 , and desirable cycling durability with approximately 75 % specific capacitance retention after 5000 consecutive cycles at a current rate of 2 A g -1 . These electrochemical investigations strongly indicated that the as-fabricated hollow NiCo 2 S 4 NBs can be elegantly utilized as powerful candidates for advanced electrode platforms., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this contribution, we purposefully designed hierarchical hydrogenated TiO2 spheres (HTSs) constructed from ultrathin anatase nanosheets with highly exposed (001) facets, and further utilized them as an efficient encapsulated host of sulfur species for advanced Li-S batteries (LSBs). Strikingly, the as-fabricated hybrid S/HTSs cathode exhibited high Coulombic efficiency (>94%), exceptional long cycling performance (capacity decay of ∼0.399% per cycle at 0.5 C), and large reversible discharge capacity (∼579 mAh g(-1) at 2.0 C) at high C rates, benefiting from better electronic conductivity, smaller charge transfer resistance and strong chemical bonding between [Formula: see text] and the reduced (001) facets of HTSs, according to experimental measurements and systematical theoretical calculations. More significantly, our in-depth insights into the mechanism involved in the hybrid S/HTSs could efficiently guide future design, optimization and synthesis of other metal oxide-based matrixes with specific exposed crystal facets for next-generation advanced LSBs.

In the work, a facile and green two-step synthetic strategy was purposefully developed to efficiently fabricate hierarchical shuttle-shaped mesoporous ZnFe2 O4 microrods (MRs) with a high tap density of ∼0.85 g cm(3) , which were assembled by 1D nanofiber (NF) subunits, and further utilized as a long-life anode for advanced Li-ion batteries. The significant role of the mixed solvent of glycerin and water in the formation of such hierarchical mesoporous MRs was systematically investigated. After 488 cycles at a large current rate of 1000 mA g(-1) , the resulting ZnFe2 O4 MRs with high loading of ∼1.4 mg per electrode still preserved a reversible capacity as large as ∼542 mAh g(-1) . Furthermore, an initial charge capacity of ∼1150 mAh g(-1) is delivered by the ZnFe2 O4 anode at 100 mA g(-1) , resulting in a high Coulombic efficiency of ∼76 % for the first cycle. The superior Li-storage properties of the as-obtained ZnFe2 O4 were rationally associated with its mesoprous micro-/nanostructures and 1D nanoscaled building blocks, which accelerated the electron transportation, facilitated Li(+) transfer rate, buffered the large volume variations during repeated discharge/charge processes, and provided rich electrode-electrolyte sur-/interfaces for efficient lithium storage, particularly at high rates., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We have purposefully developed a smart template-engaged methodology to efficiently fabricate well-defined ternary spinel ZnMn2 O4 hollow nanotubes (NTs). The procedure involves coating carbon nanotubes (CNTs) with ZnMn2 O4 nanosheets (NSs), followed by heating at high temperature in air to oxidize the CNT template. Physicochemical characterization demonstrated that the formed ZnMn2 O4 NTs with a diameter of approximately 100 nm were composed of assembled NSs and/or nanoparticles (NPs) as building blocks and possessed numerous nanopores of several nanometers in the sidewall of the NTs. In favor of the intrinsic structural advantages, the resulting ZnMn2 O4 NTs exhibited superior electrochemical lithium-storage performance with a large capacity, good rate behavior, and excellent cyclability when evaluated as promising anodes for lithium-ion batteries (LIBs). The remarkable electrochemical performance was rationally ascribed to the appealing one-dimensional (1D) porous hollow tubular architecture with nanoscale subunits and mesopores in the sidewalls, which decreased the diffusion length for the Li(+) ions, improved the kinetic process, and enhanced the structural integrity with sufficient void space to tolerate the volume variation during Li(+) -ion insertion/extraction. These results highlight the promising application of 1D ZnMn2 O4 NTs as anodes for high-performance LIBs., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, we put forward a facile yet efficient room-temperature synthetic methodology for the smart fabrication of mesoporous nanocrystalline ZnMn2O4 in macro-quality from the birnessite-type MnO2 phase. A plausible reduction/ion exchange/re-crystallization mechanism is tentatively proposed herein for the scalable synthesis of the spinel phase ZnMn2O4. When utilized as a high-performance anode for advanced Li-ion battery (LIB) application, the as-synthesized nanocrystalline ZnMn2O4 delivered an excellent discharge capacity of approximately 1288 mAh g(-1) on the first cycle at a current density of 400 mA g(-1), and exhibited an outstanding cycling durability, rate capability, and coulombic efficiency, benefiting from its mesoporous and nanoscale structure, which strongly highlighted its great potential in next-generation LIBs. Furthermore, the strategy developed here is very simple and of great importance for large-scale industrial production., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We present a robust strategy for assembling and disassembling of highly luminescent blue emitting Zn(x)Cd(1-x)S/dodecylamine (DDA) complexes via a facile water/chloroform interface. Firstly, thioglycolic acid (TGA)-stabilized ternary Zn(x)Cd(1-x)S nanocrystals (NCs) were synthesized in aqueous solution. And then, relying upon the facile water/chloroform interfacial platform, such NCs are assembled into the flake-like microstructures under the direction of DDA molecules when the pH of the water phase is adjusted into an optimal acidic range. Simultaneously, the NCs are transferred from the water into the chloroform phase due to the electrostatic interactions between carboxyl groups and amino of DDA molecules. Interestingly, by reversibly adjusting the pH of the water phase into an optimal basic range, the flake-like Zn(x)Cd(1-x)S/DDA complexes are disassembled into separate NCs and DDA, and these NCs are reversibly transferred back into the water phase. The photoluminescence (PL) quantum yield (QY) of Zn(x)Cd(1-x)S/DDA complexes after interfacial assembly is improved to 55% from 6%. Particularly, a QY of about 22% still retains for the Zn(x)Cd(1-x)S NCs even after the interfacial disassembly., (Copyright 2010 Elsevier Inc. All rights reserved.)

We report a new available strategy for fabricating 2-dimensional petal-like CdS/dodecylamine (DDA) hybrids with enhanced photoluminescence (PL) by using a method of oil/water interfacial self-assembly. First, water-soluble CdS nanocrystals (NCs) were controllably prepared at the two-phase interface by injecting the Na2S solution into CCl4 phase. And then, the as-synthesized CdS NCs (ca. 4 nm) were transferred from the water to the CHCl3 phase under the direction of DDA. Finally, through the electrostatic interactions between the positively charged amino of DDA and the negatively charged the ligand of NCs surface, we have successfully fabricated petal-like CdS/DDA hybrids via the interfacial self-assembly between the as-synthesized CdS NCs and DDA. The properties of as-prepared CdS NCs and their hybrids were thoroughly investigated by ultraviolet-visible (UV-vis), transmission electron microscope (TEM), Fourier transform infrared spectra (FT-IR), photoluminescence (PL), scanning electron microscopy (SEM) measurements. We have found that these petal-like CdS/DDA hybrids after interfacial self-assembly exhibit good PL property and higher quantum yield.