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Solid-state lithium metal batteries (LMBs) have been extensively investigated owing to their safer and higher energy density. In this work, we prepared a novel elastic solid-state polymer electrolyte based on an in situ-formed elastomer polymer matrix with ion-conductive plasticizer crystal embedded with Li6.5La3Zr1.5Ta0.5O12 (LLZTO) nanoparticles, denoted as LZT/SN-SPE. The unique structure of LZT/SN-SPE shows excellent elasticity and flexibility, good electrochemical oxidation tolerance, high ionic conductivity, and high Li+ transference number. The role of LLZTO filler in suppressing the side reactions between succinonitrile (SN) and the lithium metal anode and propelling the Li+ diffusion kinetics can be affirmed. The Li symmetric cells with LZT/SN-SPE cycled stably over 1100 h under a current density of 5 mA cm−2, and Li||LiFePO4 cells realized an excellent rate (92.40 mAh g−1 at 5 C) and long-term cycling performance (98.6% retention after 420 cycles at 1 C). Hence, it can provide a promising strategy for achieving high energy density solid-state LMBs. [ABSTRACT FROM AUTHOR]

TaS2 as transition metal dichalcogenide (TMD) two-dimensional (2D) material has sufficient unstructured bonds and large inter-layer spacing, which highly supports transporting and absorbing mercury ions. The structural characterizations and simulation data show that an SPR sensor with high sensitivity can be obtained with a TaS2 material-modified sensitive layer. In this paper, the role of TaS2 nanoparticles in an SPR sensor was explored by simulation and experiment, and the TaS2 layer in an SPR sensor was characterized by SEM, elemental mapping, XPS, and other methods. The application range of structured TaS2 nanoparticles is explored, these TaS2 based sensors were applied to detect Hg2+ ions at a detection limit approaching 1 pM, and an innovative idea for designing highly sensitive detection techniques is provided. [ABSTRACT FROM AUTHOR]

In recent years, spatial self‐phase modulation (SSPM) with two‐dimensional (2D) materials has attracted the attention of many researchers as an emerging and ubiquitous nonlinear optical effect. In this review, the state of the art of 2D material‐based SSPM is summarized. SSPM measures or tunes the nonlinearity of 2D materials, and it is also an effective approach to study the band structure of 2D materials. Several modified forms of SSPM, such as high‐order, white‐light‐excited, vector field excited, and optically nonlinearly enhanced SSPM are also presented. Subsequently, the physical origin of the SSPM formation mechanism is compared and analyzed. Furthermore, the applications of SSPM with 2D materials, including passive photonic devices, generation of Bessel beams, and identifying the mode of the orbital angular momentum, are listed. Finally, several urgent problems of the SSPM with 2D materials, potential applications, and prospects for future development are presented. [ABSTRACT FROM AUTHOR]

Boron nanosheets possess unique photoelectric properties, including photosensitivity, photoresponse, and optical nonlinearity. In this article, we show the interaction between light and boron nanosheets in which concentric rings formed in the far field, which attributed to the strong Kerr nonlinearity of boron nanosheets. Furthermore, the distortion, regulation and relationship between the Kerr nonlinearity and effective mass or carrier mobility of the diffraction rings of boron nanosheets have been investigated. Our work shows that the spatial self-phase modulation effect of boron nanosheets is indeed caused by nonlocal electronic coherence. In addition, we have implemented all-light modulation and all-light logic gates based on the prepared boron nanosheets. We believe that our results will provide a powerful demonstration of nonlinear photonic devices based on boron nanosheets and a reference for photonic devices based on two-dimensional materials. [ABSTRACT FROM AUTHOR]

The nonlinear optical response of 2D materials has attracted wide attention in the recent year due to their strong nonlinearity and broadband characteristics. A new optical scheme is presented enabling the implementation of the broadband nonlinear optical response and their all‐optical applications of few‐layered InSe nanosheets. First, few‐layer InSe nanosheets are synthesized by using the liquid‐phase exfoliated method; then the third‐order nonlinear susceptibility is measured with the spatial self‐phase modulation. Based on the obtained nonlinear optical response, a method is proposed for forming a nonreciprocal propagation photonic diode based on a mixed structure of InSe/C3N4. In addition, through the cross‐phase modulation of the two beams, the all‐optical switches and all‐optical information conversion have also been discussed. The implementations of these few‐layered InSe‐based all‐optical devices show that the layered InSe is indeed an excellent candidate for use in future all‐optical photonic circuits as an optical diode and optical switching. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) have been gotten attention owing to high energy density. In here, the production of PEO-xLiNO 3 solid electrolyte with LiNO 3 as the sole lithium salt is cost-effective, environmentally friendly, and convenient. The interaction of the electrolyte and the electrode can form a uniform and dense solid-electrolyte interphase (SEI) layer packing L 3 iN and LiN x O y groups, which will effectively control lithium deposition and inhibit dendrite growth. The electrolyte exhibits outstanding mechanical properties, remarkable room temperature ionic conductivity, and the ability to suppress lithium dendrite growth. When applied in symmetric Li//Li batteries, the electrolyte shows excellent cycling stability with over 5000 h of cycling at a current density of 0.1 mA cm−2. For NCM622//Li batteries after full charge, it exhibits good cycling stability with a capacity retention rate is as high as 88 % after 300 cycles. Hence, the proposed electrolyte not only enhances safety performance but also improves electrochemical properties, making it highly promising for large-scale practical applications. [ABSTRACT FROM AUTHOR]

2D Tantalum disulphide (TaS 2) has been widely studied as a typical transition metal dichalcogenides (TMDCs) with excellent optical, chemical and electrochemical properties. However, there is little research on the comprehensively characterizing the interaction between light and the 2D TaS 2 material. In this work, we studied the nonlinear optical response of the high quality few-layer TaS 2 nanosheets and its all-optical applications. Our research shows that 2D TaS 2 nanosheet has a broadband characteristic and exhibits a strong Kerr nonlinear optical response based on the spatial self-phase modulation (SSPM). More importantly, by taking advantage of the highly nonlinear optical response of the2D TaS 2 , typical all-optical phenomena, such as all-optical switching and nonreciprocal light propagation, have been demonstrated experimentally. This work can be viewed as an important demonstration of a TMDCs-based application prototype in nonlinear photonics, which could potentially indicate an essential step toward miscellaneous TMDCs-based passive photonic devices (all-optical diodes, all-optical switches, etc.) • Spatial self-phase modulation of 2D TaS 2 was demonstrated firstly. • Broadband and strong Kerr nonlinear optical response of 2D TaS2 were confirmed. • All-optical switching has been realized with 2D TaS 2. • Nonreciprocal light propagation and all-optical diode were designed with 2D TaS 2. [ABSTRACT FROM AUTHOR]

Boron nitride nanotubes (BNNTs), the one-dimensional member of the boron nitride nanostructure family, are generally accepted to be highly inert to oxidative treatments and can only be covalently modified by highly reactive species. Conversely, it is discovered that the BNNTs can be chemically dispersed and their morphology modified by a relatively mild method: simply sonicating the nanotubes in aqueous ammonia solution. The dispersed nanotubes are significantly corroded, with end-caps removed, tips sharpened, and walls thinned. The sonication treatment in aqueous ammonia solution also removes amorphous BN impurities and shortened BNNTs, resembling various oxidative treatments of carbon nanotubes. Importantly, the majority of BNNTs are at least partially longitudinally cut, or 'unzipped'. Entangled and freestanding BN nanoribbons (BNNRs), resulting from the unzipping, are found to be ∼5-20 nm in width and up to a few hundred nanometers in length. This is the first chemical method to obtain BNNRs from BNNT unzipping. This method is not derived from known carbon nanotube unzipping strategies, but is unique to BNNTs because the use of aqueous ammonia solutions specifically targets the B-N bond network. This study may pave the way for convenient processing of BNNTs, previously thought to be highly inert, toward controlling their dispersion, purity, lengths, and electronic properties. [ABSTRACT FROM AUTHOR]

The design of new materials is an important subject in order to attain new properties and applications, and it is of particular interest when some peculiar topological properties such as reduced dimensionality and rule-breaking chemical bonding are involved. In this work, we designed a novel two-dimensional (2D) inorganic material, namely Be2C monolayer, by comprehensive density functional theory (DFT) computations. In Be2C monolayer, each carbon atom binds to six Be atoms in an almost planar fashion, forming a quasi-planar hexacoordinate carbon (phC) moiety. Be2C monolayer has good stability and is the lowest-energy structure in 2D space confirmed by a global minima search based on the particle-swarm optimization (PSO) method. As a semiconductor with a direct medium band gap, Be2C monolayer is promising for applications in electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

The design of new materials is an important subject in order to attain new properties and applications, and it is of particular interest when some peculiar topological properties such as reduced dimensionality and rule-breaking chemical bonding are involved. In this work, we designed a novel two-dimensional (2D) inorganic material, namely Be2C monolayer, by comprehensive density functional theory (DFT) computations. In Be2C monolayer, each carbon atom binds to six Be atoms in an almost planar fashion, forming a quasi-planar hexacoordinate carbon (phC) moiety. Be2C monolayer has good stability and is the lowest-energy structure in 2D space confirmed by a global minima search based on the particle-swarm optimization (PSO) method. As a semiconductor with a direct medium band gap, Be2C monolayer is promising for applications in electronics and optoelectronics. [ABSTRACT FROM AUTHOR]

The FeCoS2/rGO was synthesized by a one-step hydrothermal method, which has the advantages of environmental friendliness and low cost. Dense and homogeneous FeCoS2 nanodots are dispersed in the reduced graphene oxide flakes, which is beneficial to improve catalytic activity. Compared with FeS2/rGO, FeCoS2/rGO exhibits much higher initial discharge capacity and much better capacity retention ratio. The lower activation energy and the relatively narrow peak shape and small reduction/oxidation peak spacing show that FeCoS2/rGO have better catalytic activity than FeS2/rGO. It can be also confirmed by first-principles calculation that the adsorption energy of the Fe site (− 1.8334 eV) and the Co site (− 1.7539 eV) on the FeCoS2 surface is better than that of FeS2. So, the synergistic reaction of Fe and Co will adjust microregional electron density and change binding energy to polysulfides. [ABSTRACT FROM AUTHOR]

The development of high-performance solid-polymer electrolytes (SPEs) is a key to the practical application of lithium metal batteries (LMBs). The use of two-dimensional (2D) inorganic nanofiller is an efficient way to build poly(ethylene oxide) (PEO)-based SPEs with high ionic conductivity and stability. Herein, a series of 2D oxygen vacancy-rich Co3O4-y−x (x = 1, 2 and 3) with well-defined 2D nanostructures, a high surface area and controllable oxygen vacancy contents (Co3O4-y) was synthesized via a facile self-assembly method and NaBH4 reduction. When the 2D Co3O4-y−x (x = 1, 2 and 3) nanosheets are introduced as nanofillers in PEO-based SPEs, they can interact with the PEO to form a three-dimensional (3D) PEO/Co3O4-y film with uniform Li+ distribution and vertical diffusion channels, as well as strong adsorption of NO3− from LiNO3 electrolyte salt at the defective sites. As a result, the PEO/Co3O4-y−2 film reached a high ionic conductivity of 4.9 × 10−5 S cm−1, high Li+ a transference number of 0.51 and a wide electrochemical window over 4.6 V at 80 °C. The PEO/Co3O4-y−2 film enables the Li||PEO/Co3O4-y−2||LiFePO4 cell to deliver a high reversible capacity of 117.7 mAh g−1 at 2 C and to maintain 126.7 mAh g−1 at 1 C after 250 cycles with an initial capacity retention of 87.9%. [ABSTRACT FROM AUTHOR]

First-principles computations were performed to investigate the uniform bending effect on the electronic properties of armchair boron nitride nanoribbons (aBNNRs) with experimentally obtained width. For both bare and hydrogen-terminated aBNNRs, the band gaps only slightly depend on the uniform bending. The insensitivity of the band structures of BNNRs to the uniform bending makes them ideal materials when their wide band gap character is desired. [ABSTRACT FROM AUTHOR]

• We have developed a novel sensor based on niobium disulfide high perfect performance. • The maximum value of SPR sensitivities approached to 193°∕RIU achieved by coating the NbS 2 nanosheets in simulation calculation. • These sensors were used to detect mercy and the value of sensitivity is 13.55°∕μM, and detection limit approach 1 pM. Mercury ion (Hg2+) can affect the quality of water and cause damage to human health. Therefore, the detection of Hg2+ in water, especially trace Hg2+, is very important. However, the detection limit (approximately 200 pM) of conventional Hg2+ sensors is far lower than the detection limit (7.5 pM) proposed by the US Environmental Protection Agency for measuring Hg2+. Here, we have developed a novel sensor based on niobium disulfide (NbS 2)'s high perfect performance. The maximum value of SPR sensitivities approached to 193°∕RIU achieved by coating the NbS 2 nanosheets in simulation calculation, which had increased by 38.1% compared with the case without NbS 2 overlayer. More importantly, this work also detected the ultra-low concentration of Hg2+ and describes the sensing mechanism of NbS 2 based SPR sensors. Surprisingly, these sensors were used to detect mercury and the value of sensitivity is 13.55°∕μM, and detection limit approach 1 pM. NbS 2 nanosheets based SPR sensors provided innovative design ideas for the development of ultra-sensitive detection technology. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials exhibit interesting nonlinear optical properties, and they have been used in bioimaging, ultrafast photon and all-optical switch devices. Boron nanosheets is a recently emerging 2D material that has attracted the attention of a large number of researchers. In this work, the saturation absorption (SA) effect of boron nanosheets has been investigated through a typical z-scan method, it is demonstrated that the nonlinear absorption coefficient and the quality factor are greatly improved compared with the other 2D materials such as black phosphorus, MoS 2 and Ti 3 C 2 T x. By combining the all-optical modulation and z-scan technology, the competition between the laser intensity-dependent SA and nonlinear scattering in boron nanosheets are revealed, and hence the optically-induced transparency and optically-induced extinction in nanosecond regime have been confirmed. Based on this competitive effect, an effective modulation of continuous light (λ = 671 nm) by nanosecond pulses (λ = 532 nm) has been realized, the maximum modulation depth of 5.5 dB is obtained. • The optically-induced transparency and optically-induced extinction in nanosecond regime have been confirmed. • An effective modulation of continuous light (λ = 671 nm) by nanosecond pulses (λ = 532 nm) has been realized, the maximum modulation depth of 5.5 dB is obtained. [ABSTRACT FROM AUTHOR]

The sluggish conversion kinetics of polysulfides and its unprevented dissolution will lead to loss of active sulfur and act as the biggest obstacle for the widespread use of lithium-sulfur (Li-S) batteries. However, it is a great challenge to simultaneously response to the above-mentioned multiple requirements by the adoption of single catalyst. Herein, by incorporating the merits of strong adsorption and high electron conductivity of Ni 3 S 2 with good catalytic of MoS 2 , a self-supported heterojunction MoS 2 -Ni 3 S 2 catalyst has been developed with uniform rod-like morphology, which can provide larger specific surface area, better compensation of electrons, more effective catalysis, and faster solid phase transformation compare to its single component catalyst. Theoretical calculations and mechanism analyses suggest that the heterojunctions exhibit a synergistic process of "adsorption-diffusion-conversion" for polysulfides (LiPSs) and effectively facilitate the liquid-solid phase conversion(Li 2 S 6 →Li 2 S 2 /Li 2 S). Integrating the merits of Ni 3 S 2 and MoS 2 , MoS 2 -Ni 3 S 2 heterojunctions catalytic cathode deliver a good cycling stability with 70 % capacity retention after 150 cycles at 0.2 C with a high sulfur loading of 5.0 mg cm−2. Therefore, this work proposed a feasible catalyst design of bi-metal sulfides heterostructure which can simultaneously meet multiple kinetics requirements of Li-S system. • Designing a self-supported heterojunction MoS 2 -Ni 3 S 2 catalyst to achieve efficient catalysis in Li-S battery. • Investigating the "adsorption-diffusion-conversion " synergistic catalytic effect. • Enhancing the liquid-solid phase conversion(Li 2 S 6 →Li 2 S 2 /Li 2 S) in Li-S batteries. [ABSTRACT FROM AUTHOR]

Lateral surface etching of two-dimensional (2D) nanosheets results in holey 2D nanosheets that have abundant edge atoms. Recent reports on holey graphene showed that holey 2D nanosheets can outperform their intact counterparts in many potential applications such as energy storage, catalysis, sensing, transistors, and molecular transport/separation. From both fundamental and application perspectives, it is desirable to obtain holey 2D nanosheets with defined hole morphology and hole edge structures. This remains a great challenge for graphene and is little explored for other 2D nanomaterials. Here, a facile, controllable, and scalable method is reported to carve geometrically defined pit/hole shapes and edges on hexagonal boron nitride (h-BN) basal plane surfaces via oxidative etching in air using silver nanoparticles as catalysts. The etched h-BN was further purified and exfoliated into nanosheets that inherited the hole/edge structural motifs and, under certain conditions, possess altered optical bandgap properties likely induced by the enriched zigzag edge atoms. This method opens up an exciting approach to further explore the physical and chemical properties of hole- and edge-enriched boron nitride and other 2D nanosheets, paving the way toward applications that can take advantage of their unique structures and performance characteristics. [ABSTRACT FROM AUTHOR]

Two-dimensional Be2C monolayers, in which each carbon atom binds to six Be atoms in an almost planar fashion, are characterized by DFT calculations. [ABSTRACT FROM AUTHOR]

On page 4497, Z. Chen, J. W. Connell, Y. Lin, and co‐workers demonstrate a method to disperse and chemically modify the morphology of BNNTs via sonication in aqueous ammonia solutions. While BNNTs have always been considered chemically inert, the ammonia‐modified BNNTs are significantly corroded and exhibit end‐cap removal, tip sharpening, wall thinning, length shortening, and longitudinal unzipping. This could lead to an effective purification technique for BNNTs by removing amorphous BN fragments from production. [ABSTRACT FROM AUTHOR]

The back cover of the journal "Angewandte Chemie: A Journal of the Gesellschaft Chemiker" is presented.

The melt migration and solidification behavior on the surface of metal structure and in the debris voids is a key phenomenon of debris bed melting, which has an important impact on the assessment of reactor pressure vessel damage and melt leakage. In this study, the moving particle semi-implicit (MPS) method with high-order discretization scheme was coupled with a surface tension model that was established based on interface reconstruction. The migration and solidification behavior of UO 2 –ZrO 2 and Fe–Zr melts on the metal structure surface and in the debris voids were investigated with the improved MPS method. The effects of temperature, velocity, contact angle and droplet diameter on the melt migration and solidification were analyzed. The results showed that the molten UO 2 –ZrO 2 droplet on the metal structure surface presented three stages with solidification rate decreasing, while the solidification rate of molten Fe–Zr droplet had little change. The maximum spread factor and solidification rate increased with the increase of droplet falling velocity, but the spread factor was independent of the melt type at the same velocity. The high-temperature molten droplet penetrated the voids formed by the debris with diameter of 5 mm more easily compared to the voids formed by the debris with diameter of 3 mm. The influence of contact angle on the migration of molten droplet with initial velocity was small, and the maximum difference in droplet mass fraction was about 6%. Three groups of molten droplets with different diameters penetrated the voids, and the average increments of penetration mass fraction were 2.3%, 2.7% and 5.8%, respectively, with the increase of velocity. Near the bottom of the debris bed, the molten droplet without initial velocity solidified and blocked the flow channel, but the molten droplet with initial velocity of 0.5 m/s penetrated through the debris voids. The droplet with initial velocity of 0.5 m/s had a faster solidification rate in the voids compared to the droplet without initial velocity, and the droplet solidification mass fraction was 96.27% when the initial melt temperature was 1410 K. [ABSTRACT FROM AUTHOR]

• The behavior of cladding melting and melt migration in lead-cooled coolant was studied. • The viscosity function was used to evaluate the cladding viscosity at different enthalpies. • Surface tension promoted the molten cladding to adhere on fuel rod surface. • The "center-peaked distribution" case was easy to cause re-solidified metal in the upper part of the fuel rod. • Flowing coolant accelerated the cooling of melt and softened cladding. The behavior of cladding melting and melt migration is an important phenomenon during the early stage of core disruptive accidents (CDA) in lead-cooled fast reactors (LFRs), which can affect the accident evolution trend and severity. In this paper, the Moving Particle Semi-implicit (MPS) method with the advantage of phase-interface capture was employed to further reveal this key phenomenon. In the simulation, the cladding was regarded as a high-viscosity fluid, and the viscosity function related to solid fraction was used. Meanwhile, the modified algorithm with the viscosity term being placed after the pressure term was adopted to ensure the cladding was stationary before the temperature reached the melting point. The computational model was verified by the experiments of tin cladding tube melting and melt migration in seven-pin bundle. After that, the effects of surface tension coefficient, fuel initial temperature and coolant flow speed on cladding melting and melt migration in lead-bismuth coolant were investigated with the improved MPS method. The results indicated that surface tension promoted the melt to adhere on fuel rod surface and the melt-coolant contact area decreased when the surface tension was introduced. The fuel initial temperature with "center-peaked distribution" caused a temperature gradient in the flow channel and led to re-solidified metal at the upper part of the fuel rod. Compared with the "uniform distribution" case, the size of molten droplet in "center-peaked distribution" case was smaller and more fragmented droplets could be observed. When the lead-bismuth coolant was flowing, the enhanced heat transfer accelerated the cooling of melt as well as softened cladding, and the solidified melt blocked the flow channel at the midstream and downstream regions. [ABSTRACT FROM AUTHOR]

With the aim of tackling insufficient security in the chaotic encryption algorithm for digital images in the Optical Access Network, a color image encryption scheme combining non-degenerate discrete hyperchaotic system and deoxyribonucleic acid (DNA) dynamic encoding is proposed. First, a new non-degenerate hyperchaotic system is constructed with all positive Lyapunov and more complex dynamic characteristics. Furthermore, the key sequence based on non-degenerate hyperchaotic system is generated using plaintext correlation to achieve the effect of a dynamic secret key. Next, a binary bit-planes permutation is performed on the image using one of the key sequences. Then, the chaotic key sequence is used to sequentially perform DNA encoding, obfuscation, and decoding. Finally, a binary bit-planes obfuscation is performed to obtain the final ciphertext. The research results show that the non-degenerate chaotic sequence can pass the NIST 800-22 test, and the corresponding encryption algorithm can resist various common attacks and has a strong anti-interference ability. In addition, the algorithm is verified on ARM-Embedded, which proves that the encryption system proposed in this paper is a feasible secure communication technology scheme. Therefore, the scheme proposed in this paper is helpful to provide new ideas for the design and application of high-security cryptosystem in optical access network. [ABSTRACT FROM AUTHOR]

In the current network and big data environment, the secure transmission of digital images is facing huge challenges. The use of some methodologies in artificial intelligence to enhance its security is extremely cutting-edge and also a development trend. To this end, this paper proposes a security-enhanced image communication scheme based on cellular neural network (CNN) under cryptanalysis. First, the complex characteristics of CNN are used to create pseudorandom sequences for image encryption. Then, a plain image is sequentially confused, permuted and diffused to get the cipher image by these CNN-based sequences. Based on cryptanalysis theory, a security-enhanced algorithm structure and relevant steps are detailed. Theoretical analysis and experimental results both demonstrate its safety performance. Moreover, the structure of image cipher can effectively resist various common attacks in cryptography. Therefore, the image communication scheme based on CNN proposed in this paper is a competitive security technology method. [ABSTRACT FROM AUTHOR]

Abstract Mullite whiskers were successfully in-situ synthesized in phosphate-based adhesive by taking Si and Al(OH) 3 as reaction sources and AlF 3 as the catalytic initiator. After calcination at 1300 °C, both strength and toughness of whisker-growth adhesive got greatly improved, which were increased by 75% and 156%, respectively. The bonding strength was enhanced to 23.8 MPa, which was close to some hot preceramic polymer-based adhesives. An approximate yield stage appeared on its corresponding loading-curve, showing unprecedented toughness and high damage capacity. In addition, the residual rate of bonding strength still maintained 63% after 20 thermal cycles (room temperature-1300 °C). [ABSTRACT FROM AUTHOR]

• Design a nano-hybrid anode with CNT framework interlacing MnO nanoparticles. • Macro-porous structure limit volume expansion and achieve stable SEI overlayer. • Self-supported MnO@CNT meet the comprehensive requirements of lithium ion battery. • MnO@CNT anode show excellent electrochemical performance. Nano-structure design and carbonous coupling are the most popular strategies to tackle the shortcomings of MnO-based anode materials. Herein, a nano-hybrid MnO anode is constructed with a self-supported carbon nanotube (CNT) framework interlacing MnO nanoparticles, denoted as MnO@CNT. The CNT can spontaneously agglomerate and form a self-supported macro-porous MnO@CNT sphere with interconnected CNT framework and abundant inner channels, which is beneficial for e− transport, Li+ conduction, and kinetics propulsion. The macro-porous structure delivers abundant interior volume to limit the outer expansion of the MnO@CNT anode, which effectively improves the solid electrolyte interface (SEI) stability, particle integrity, and cycling stability. Excellent cycling stability of over 750 cycling life and over 99% Coulombic efficiency can be achieved by the MnO@CNT anode, which is demonstrated to be closely related to the multi-functionalities of the hybrid structure. Therefore, our work provides an effective design idea and mechanism investigation for the high-capacity manganese oxide-based anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

The search of alternatives to the commercial electrodes is a key to the development of advanced lithium ion batteries (LIBs). Compared to extensive efforts and progress made on their anode applications for LIBs, the graphene and its derivatives as cathodes have attracted less concerns. Herein, a series of reduced holey graphene oxides (rhG- x) with different "worm-like" and holey structures were synthesized based on the modified Hummer's treatment and thermal reduction of graphite anode from spent LIBs. Benefiting form the rhG- x annealed at x = 400 °C with optimized oxygen-containing groups and electronic conductivity, as well as the "worm-like" and holey structures, the rhG-400 as cathode for LIBs delivers a high reversible capacity (e.g. , 109.6 mAh g−1 at 0.05 A g−1) and excellent rate capability (e.g. , 75.0, 68.2, 50.3 and 37.0 mAh g−1 at 2, 5, 10 and 20 A g−1, respectively) and maintains an ultra-long cycling life over 2000 cycles with high reversible capacity of 137.4 mAh g−1. [Display omitted] [ABSTRACT FROM AUTHOR]