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It is a confused problem in the literature that the c- axis value of Ti 3 C 2 MXene changes with the synthesis procedure, but the part of the surface structures that plays the role of pillar to support the Ti 3 C 2 layers and their variation rules remain controversial. In this work, we develop the structure models and formation mechanisms of Ti 3 C 2 T x based on the density functional theory calculations and experimental results. While the c- axis values of the samples vary from about 1.9 to 2.9 nm, the corresponding pillars are determined by different distributions and proportions of the H-containing groups. The proportions of the H-containing groups that determine the c- axis value are formulated as the functions of the interlayer space, which can be used to quantitatively clarify the changes of the surface functional groups after the samples experiencing different treatments. The results can facilitate the in situ detections of the surface structures of MXenes during different treatments or electrochemical processes. [ABSTRACT FROM AUTHOR]

Layered titanium carbide (Ti 3 C 2 ) has been synthesized by exfoliation of ternary carbides Ti 3 AlC 2 and evaluated as working electrodes with different mass loading from 1.8 mg to 7.6 mg. The effect of mass loading on the electrochemical properties of Ti 3 C 2 electrodes was studied by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD) and impedance spectrum test. With increasing of Ti 3 C 2 mass from 1.8 to 7.6 mg/cm 2 in electrode, the specific capacitance calculated from the CV curves at 2 mV/s decreases at first from 117 to 78 F/g then maintains at 76 F/g, while areal capacitance increases from 211 to 579 mF/cm 2 . Moreover, both electrodes with low mass loading (1.8 mg) and large mass loading (7.6 mg) have delivered good cycling performances with capacitance retention of 97% and 98% after 10000 cycles. These results indicate that large mass loading electrode retains high specific capacitance and good cycling stability, due to the excellent electronic conductivity and layered structure of Ti 3 C 2 . [ABSTRACT FROM AUTHOR]

Many conflicting electron microscopy data for In 2 O 3 (ZnO) m indicate that it may have the polymorphous and polytypoid structures. We investigate their stabilities based on four controversial models. The calculated results confirm that the models with the zigzag feature are more stable than the others and it is possible to form different zigzag configurations in the samples as observed in the experiments. The dynamic process of eliminating the dangling bonds and the requirements of maximizing the symmetry and the distances between the In atoms in the slabs can be regarded as the dominant rules to stabilize the system, but the statistical equilibrium processes have the chances to transform it from the ground state structures to the other model structures. The study of the electronic structures based on the plane and zigzag models reveals that their band gaps and effective masses increase monotonically with m . The predicted band gaps are consistent with the experimental results. The anisotropic feature of electron effective mass tensor exhibited in the plane model differs from that of the zigzag one, which is so notable that can be employed to determine which model is more close to the actual structure of a given sample. The calculated results confirm the possibilities of the separation of conduction electrons and defects and the existence of the natural optimized transport channels in the layered structures, which demonstrate its advantage over ZnO to transport electrons and benefit its applications in the optoelectronic devices. [ABSTRACT FROM AUTHOR]

The diameter-dependent luminescence properties for individual ZnO wires were systematically investigated by means of a spatially resolved spectroscopic technique. The two-dimensional photoluminescence (PL) mapping image was presented to show the integrated optical emission properties at each position of the wire. A blue shift of the UV emission peak was directly observed as the diameter gradually decreased from 400 to 100 nm. The two-dimensional PL intensity map of the ultraviolet emitted energy at 3.26 eV for the ZnO wire was shown along the length and width of the wire. The observed results indicate that the PL integrated intensity distribution is not uniform along the wire. The mechanisms of the blue shift and the intensity distributions for the PL spectrum along the wire are proposed based on PL mapping, the Burstein–Moss effect and semiconductor theory. [ABSTRACT FROM AUTHOR]

Abstract: Novel hierarchical ZnO hexagonal towers were fabricated via chemical vapor deposition for the first time by adding trace Fe power in the precursor as a catalyst. The scanning electron microscopy images showed that the outside surface of novel hierarchical ZnO hexagonal towers was layer-by-layer assembly. X-ray diffraction pattern indicated that the hierarchical ZnO hexagonal towers grew preferentially along the [0001] direction. Intense UV emission centered at 380nm was observed at room temperature. Moreover, their field-emission properties were studied. A low turn-on electric field of 2.37Vμm−1 and high field enhancement factor of about 2691 were obtained, due to the novel layer structure and high crystalline quality. This kind of hierarchical ZnO microstructures could be a good candidate for high performance field emission devices. [Copyright &y& Elsevier]

Abstract: Uniform and smooth AlN nanosheets were fabricated on Si substrates by a vapour-phase transport method, using Al powder and ammonia as the source materials. Their morphology and structure were examined by scanning and transmission electron microscopy, and X-ray diffraction. They have a perfect rectangular shape. The growth is favoured along the and crystallographic directions within the plane. Their growth mechanism is discussed on the basis of data gathered. The linewidth of (high) longitudinal optical phonon mode is about 7 cm−1, indicating their high quality. Their photoluminescence property is also investigated. [Copyright &y& Elsevier]

Abstract: Super-uniform single crystal ZnO nanohelices synthesized by Sb induced thermal evaporation is reported. The ZnO nanohelices as a whole have an axial direction of , perfect hexagonal cross section and length of tens of micrometres. There are six blocks in each period of the helices, and they grow along six equivalent directions . The typical pitch distance, mean diameter and thickness of the nanowire is about 600, 400 and 100 nm. Calculation according to a simple model shows that the helical structure is energetically favourable. It could be used as photonic crystals or construct blocks in nanoscale optoelectronic and electromechanical systems. In addition to ZnO nanohelices, zigzag ZnO nanostructures were also obtained. [Copyright &y& Elsevier]

Abstract: GaN nanorods were synthesized from the reaction of a Ga/Ga2O3 mixture with NH3 on Si substrates by chemical vapor deposition. The synthesized products were characterized by scanning and transmission electron microscopy, X-ray diffraction, photoluminescence and Raman spectroscopy. The nanorods are highly single crystalline and possess uniform smooth surfaces. PL revealed only a strong emission at 3.268 eV, ascribed to free exciton (FX) transitions, at room temperature; while the well-known yellow luminescence band centered at 2.2–2.3 eV was not detected. Four first-order phonon modes, corresponding to the A1(TO), E1(TO), E2(high), and A1(LO) at ∼531, 554, 564, and 721 cm−1, respectively, were observed by Raman backscattering. The red-shift of the FX emission peak and the down-shifts of the Raman modes by a few wave numbers are attributed to the presence of tensile strain inside GaN nanorods. [Copyright &y& Elsevier]

Oxygen–vacancy–reinforced perovskite promoting polysulfide conversion for lithium–sulfur batteries is investigated, which assist to guide the effect of defect concentration on the adsorption and catalytic properties of perovskites materials. [Display omitted] Lithium–sulfur batteries (LSBs) are considered to be one of the most promising energy storage systems because of the ultrahigh energy density. However, their shuttle effect and slow redox kinetics seriously hinder the development of LSBs. To solve these issues, the perovskite La 1-x Sr x MnO 3-δ (x = 0–0.5) with different oxygen vacancy concentrations were prepared by a facile liquid–phase synthesis and followed by the thermal annealing. The La 1-x Sr x MnO 3-δ can not only anchor lithium polysulfides (LiPSs), but also catalyze the conversion of LiPSs. The detailed kinetic analysis and density functional theory calculations reveal that the optimal level of oxygen vacancies can effectively increase the binding energy between perovskites and LiPSs, and effectively promote the LiPS conversion kinetics. The S/La 0.6 Sr 0.4 MnO 3-δ cathode with a moderate oxygen vacancy concentration exhibits high rate performance and ultrahigh capacity retention of 93.2% after 150 cycles at 0.1 C, which provides a potential for practical applications of LSBs. This work reveals the application of perovskite materials in the development of advanced LSBs. [ABSTRACT FROM AUTHOR]

Abstract: Single-crystalline indium-doped ZnGa2O4 nanobelts were prepared by chemical vapor deposition. Their morphology and microstructure were characterized by scanning electron microscopy and transmission electron microscopy. The cathodoluminescence results indicate that the cathodoluminescence intensity of the nanobelts was obviously enhanced compared with that of pure ZnGa2O4 nanowires. It is because the energy transfer probability from the host of ZnGa2O4 to the Ga3+ luminescence center is enhanced by In3+ doping. [Copyright &y& Elsevier]

Nanocrystalline chromium boride (CrB) powders were successfully synthesized at 600 °C through a solid-state reaction. The synthesis was carried out in an autoclave by using CrCl3, Mg and MgB2 as the reactants. The X-ray powder diffraction pattern indicates the formation of orthorhombic CrB. Transmission electron microscopy image shows that typical CrB crystallites are composed of floss-like particles with less than 10 nm in diameter and about 50–100 nm in length. Thermogravimetric analysis revealed that the oxidation resistance for nanocrystalline CrB is much lower than that of bulk CrB. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries represent one of the potential next-generation energy storage devices. However, their commercialization is hindered by the severe shuttle effect of lithium polysulfides (LiPSs) and sluggish redox kinetics. A crucial strategy to address these issues involves the rational design of catalysts and a comprehensive understanding of interaction mechanisms between catalysts and sulfur species. In this study, Fe atoms were incorporated into CoP catalysts, and one-dimensional (1D) porous carbon-encapsulated Fe-doped CoP (Co 1- x Fe x P@C) nanotube-like nanostructures were rationally designed and successfully synthesized. This design involves modifying the d–p orbital hybridization between the transition metal Co 3 d orbitals and S 2 p orbitals through the Fe 3 d orbitals, thus creating catalysts with the most effective d–p orbital hybridization and, consequently, the strongest electrocatalytic activity. Detailed kinetic analysis reveals the Co 0.75 Fe 0.25 P@C catalyst, with an effective d–p orbital hybridization, can firmly anchor the LiPSs, inhibit the shuttle effect, and facilitate bidirectional Li 2 S redox, thereby enhancing sulfur utilization and promoting LiPS conversion. These findings enable high-rate and long-cycle-life Li–S batteries. Specifically, the Li–S battery using the Co 0.75 Fe 0.25 P@C catalyst demonstrates excellent cycling stability, with a low capacity decay rate of 0.05 % per cycle over 900 cycles at 2 C. More impressively, the Li–S battery also achieves outstanding high-rate performance, delivering 726.3 mAh g–1 at 6 C. This study introduces a new strategy for identifying catalysts with the strongest electrocatalytic activity, which holds promise for advancing the development of Li−S batteries. [ABSTRACT FROM AUTHOR]

The sluggish reaction kinetics and notorious shuttle effect of polysulfides significantly hinder the practical application of lithium–sulfur batteries (LSBs). Therefore, polysulfides are anchored and their conversion reactions are catalyzed to enhance the performance of LSBs. Herein, an exquisite hierarchical carbon nanoarchitecture decorated with sulfides is designed and introduced into LSBs. Systematic experiments show that the nanoarchitecture not only enables rapid electron/ion migration but also functions as an active catalyst to increase polysulfide conversion, thus effectively reducing the shuttle effect. As a result, LSBs with the nanoarchitecture modified separator exhibited outstanding rate capacity (724.9 mA h g−1 at 5C), low self-discharge capacity loss (4.1% capacity loss after 72 h), and exceptional reversible capacity (1518.3 mA h g−1 at 0.1C and 25.6% capacity loss after 100 cycles). Through the design of a multifunctional separator, this study offers an effective way to minimize the shuttle effect and speed up redox conversion. The strategy of constructing nanoarchitectures provides an innovative route for hierarchical heterocatalyst design for LSBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 3D hierarchical MIL-53(Fe) was directly in-situ grown on the Fe Foam through the semi-sacrificial template strategy. • The optimized self-supporting electrode can run at 100 mA cm−2 for 520 h without visible decrease in activity. • MIL-53(Fe) structures was completely in-situ self-reconstructed into metal oxyhydroxides with O v after the running OER for 2 h. • DFT calculations reveal that the FeOOH with rich O v transformed from MIL-53(Fe) facilitate the OER catalytic activity. • This work provides a quick and easy method to construct a advanced self-supporting electrodes based on MOFs. The exploitation of efficient, stable and cheap electrocatalyst for oxygen evolution reaction (OER) is very significant to the development of energy technology. In this study, Fe-based metal–organic frameworks (MIL-53(Fe)) self-supporting electrode with a 3D hierarchical open structure was developed through a semi-sacrificial strategy. The self-supporting electrode exhibits an excellent OER performance with an overpotential of 328 mV at 100 mA cm−2 in 1 M KOH, which is superior than that of IrO 2 catalyst. Importantly, the optimized self-supporting electrode could operate at 100 mA cm−2 for 520 h without visible decrease in activity. It was also found that the structure of MIL-53(Fe) was in-situ self-reconstructed into oxyhydroxides during OER process. However, the 3D hierarchical open structure assembled with nano-microstructures kept well, which ensured the long-term stability of our self-supporting electrode for OER. Furthermore, density functional theory (DFT) calculations reveal that the FeOOH with rich oxygen vacancy transformed from MIL-53(Fe) plays a key role for the OER catalytic activity. And, the uninterrupted formation of oxygen vacancy during OER process ensures the continuous OER catalytic activity, which is the original source for the ultra-long stability of the self-supporting electrode toward OER. This work explores the way for the construction of efficient self-supporting oxygen electrodes based on MOFs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) currently face challenges including lithium polysulfide shuttling, sluggish sulfur redox kinetics, severe lithium dendrite growth, and volume change. Herein, an advanced dual‐functional host is designed by embedding 3D N‐doped carbon fibers with abundant 2D V2CTx nanosheets (N/CF@V2CTx). The N‐doped carbon fibers act as "thread" to connect the V2CTx nanosheets and form a unique open 3D macroporous structure. This structure effectively prevents the restacking of the V2CTx nanosheets and exposes their lithiophilic and sulfurophilic sites. Consequently, the N/CF@V2CTx host effectively suppresses the shuttling of LiPSs and improves the cathodic kinetics. Furthermore, the 3D‐ordered porous skeleton integrated with abundant lithophilic sites enables uniform Li deposition and homogeneous Li‐ion flux, thereby inhibiting dendrite growth and mitigating volume expansion. The as‐assembled LSBs exhibit excellent rate capability (640 mAh g−1 at 15 C) and outstanding cycling stability (0.019% capacity decay per cycle throughout 1200 cycles at 1 C). Moreover, the pouch cell assembled with the N/CF@V2CTx host demonstrates a high energy density of 350 Wh kg−1 and good cycling stability. This research presents a promising approach to address the challenges of both the sulfur cathode and the lithium anode comprehensively and effectively in working LSBs. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have been considered one of the most promising candidates for next-generation energy storage devices due to their high theoretical energy density and low cost. Nonetheless, the practical application of Li–S batteries is still inhibited by their lithium polysulfide (LiPS) shuttling and sluggish redox kinetics, which cause rapid capacity decay and inferior rate performance. Hence, anchoring LiPSs and catalyzing their conversion reactions are imperative to enhance the performance of Li–S batteries. In this work, one-dimensional (1D) porous carbon-encapsulated CoS2 (CoS2@C) fiber structures were prepared through a simple two-step hydrothermal reaction and they exhibited a robust LiPS trapping ability and rapid catalytic conversion of LiPSs. The formed three-dimensional (3D) architecture (CoS2@C/MWCNT) facilitates the physical adsorption of LiPSs and rapid ion transport. The electrode exhibited a high initial capacity of 1329.5 mA h g−1 at a current density of 0.1 C and a reversible capacity of 1060.6 mA h g−1 after 100 cycles, with an 80% capacity retention rate. Meanwhile, the decay rate of the electrode is 0.048% per cycle at 1 C and after 500 cycles. With a sulfur loading of 3 mg cm−2, the capacity retention rate is approximately 83.7% after 80 cycles. [ABSTRACT FROM AUTHOR]

Exploiting dual‐functional photoelectrodes to harvest and store solar energy is a challenging but efficient way for achieving renewable energy utilization. Herein, multi‐heterostructures consisting of N‐doped carbon coated MoS2 nanosheets supported by tubular TiO2 with photoelectric conversion and electronic transfer interfaces are designed. When a photo sodium ion battery (photo‐SIB) is assembled based on the heterostructures, its capacity increases to 399.3 mAh g−1 with a high photo‐conversion efficiency of 0.71 % switching from dark to visible light at 2.0 A g−1. Remarkably, the photo‐SIB can be recharged by light only, with a striking capacity of 231.4 mAh g−1. Experimental and theoretical results suggest that the proposed multi‐heterostructures can enhance charge transfer kinetics, maintain structural stability, and facilitate the separation of photo‐excited carriers. This work presents a new strategy to design dual‐functional photoelectrodes for efficient use of solar energy. [ABSTRACT FROM AUTHOR]

Exploiting dual‐functional photoelectrodes to harvest and store solar energy is a challenging but efficient way for achieving renewable energy utilization. Herein, multi‐heterostructures consisting of N‐doped carbon coated MoS2 nanosheets supported by tubular TiO2 with photoelectric conversion and electronic transfer interfaces are designed. When a photo sodium ion battery (photo‐SIB) is assembled based on the heterostructures, its capacity increases to 399.3 mAh g−1 with a high photo‐conversion efficiency of 0.71 % switching from dark to visible light at 2.0 A g−1. Remarkably, the photo‐SIB can be recharged by light only, with a striking capacity of 231.4 mAh g−1. Experimental and theoretical results suggest that the proposed multi‐heterostructures can enhance charge transfer kinetics, maintain structural stability, and facilitate the separation of photo‐excited carriers. This work presents a new strategy to design dual‐functional photoelectrodes for efficient use of solar energy. [ABSTRACT FROM AUTHOR]

Ti 3 C 2 T x has attracted great attention as negative electrode material of supercapacitors owing to its high metallic conductivity, abundant surface terminations, and suitable potential range. However, the inevitable restacking of two-dimensional nanosheets dramatically restrain the electrochemical performances of individual Ti 3 C 2 T x electrodes. In this work, interface-induced in-situ growth strategy was developed to construct W 18 O 49 /Ti 3 C 2 T x heterostructures through a simple solvothermal reaction. The optimized W 18 O 49 /Ti 3 C 2 T x hybrid electrode delivered a high specific capacitance of 472.6 F g−1 at 1 mV s−1 and retained 73.3% of its initial capacitance under 100-fold scan rate. The asymmetric supercapacitor assembled with W 18 O 49 /Ti 3 C 2 T x negative electrode and RuO 2 @CC positive electrode exhibited a high energy density of 29.6 Wh kg−1 and maximum power density of 7.0 kW kg−1. In sum, the designed negative electrode materials look promising for future use in high-energy-density supercapacitors. [Display omitted] • W 18 O 49 /Ti 3 C 2 T x heterostructure is constructed by an interface-induced in-situ growth strategy. • W 18 O 49 /Ti 3 C 2 T x electrode exhibits remarkable improved specific capacitance of 472.6 F g−1. • This study provides an efficient way to rational designation of for high energy density supercapacitors. [ABSTRACT FROM AUTHOR]

Lithium, with its high theoretical capacity and low potential, has been widely investigated as the anode in energy storage/conversion devices. However, their commercial applications always suffer from undesired dendrite growth, which forms in the charging process and may puncture the separator, leading to short cycle lives and even security problems. Herein, by an in situ displacement reaction using SnF2 at room temperature, we constructed an artificial solid electrolyte interface (ASEI) of LiF/Li–Sn outside the Li anode. This hybrid strategy can induce a synergy between the high Li+ conductivity of the Li–Sn alloy and good electrical insulation of LiF. Moreover, extreme synergy can be achieved by moderating the thickness of the LiF/Li–Sn ASEI, guiding dendrite-free lithium plating and stripping. As a result, a Li//LiFePO4 battery that is assembled from the LiF/Li–Sn ASEI-engineered Li anode can obtain 1000 cycled lives with 86.3% capacity retention under a charge/discharge rate of 5 C. This work provides an alternative way to construct dendrite-free lithium metal anodes, which significantly benefit the cycle lives of LMBs. [ABSTRACT FROM AUTHOR]

A Mo(SSe) 2-x and graphene van der Waals heterostructure with abundant anion vacancies and superior electronic conductivity is reported to enhance its hydrogen evolution reaction ability in both acidic and alkaline media. [Display omitted] The Gibbs free energy of hydrogen adsorption at the edge of molybdenum disulfide (MoS 2) is close to that of Pt, meaning that MoS 2 is the best candidate to replace Pt-based materials. However, easy agglomeration between layers to mask active sites, lack of catalytic activity in the basal planes, and poor electronic conductivity make MoS 2 exhibit dissatisfactory hydrogen evolution reaction (HER) catalytic performance. Here, we successfully construct a van der Waals heterostructure stacked alternately with Mo(SSe) 2-x and graphene (Mo(SSe) 2-x /G) to enhance its catalytic ability. The introduction of Se into MoS 2 and the thermal treatment induce the sample to generate more anion vacancies. Theoretical and experimental results demonstrate the constructed van der Waals heterostructure, the introduced Se element, and the increased anion vacancies are in favor of promoting the number of active sites and improving the electronic conductivity of the catalyst. Therefore, Mo(SSe) 2-x /G exhibits superior HER catalytic performance (the overpotentials of 137 mV and 136 mV at a current of 10 mA cm−2) and long-term stabilities (>90 h and 140 h at a current density of 20 mA cm−2) in both acidic and alkaline media. [ABSTRACT FROM AUTHOR]

CoSe 2 /CoO-CNTs catalyst was rationally designed as separator modifier for Li-S battery to selectively catalyze the sulfur species conversion via Mott-Schottky effect. [Display omitted] • CoSe 2 /CoO Mott-Schottky catalyst has been rationally designed and blended with CNTs for using as a separator modifier in Li-S battery. • CoSe 2 /CoO-CNTs synergistically utilizes the high electrocatalytic activity of CoSe 2 /CoO heterostructure and high conductivity of CNTs to selectively catalyze the sulfur species conversion via Mott-Schottky effect. • The Li-S battery with a CoSe 2 /CoO-CNTs modified separator displays a high initial discharge capacity of 1236 mAh/g at 0.5C and a low decay rate of 0.070% per cycle over 500 cycles at 2C. The lithium sulfur (Li-S) battery is an active research area in the field of energy storage systems, but the shuttle effect is a serious obstacle hindering its application. Herein, a CoSe 2 /CoO Mott-Schottky catalyst is blended with carbon nanotubes (CNTs) and subsequently coated onto a commercial separator as a modifier, whereby the synergy between the high electrocatalytic activity of the CoSe 2 /CoO heterostructure and high conductivity of the CNTs selectively mediate the conversion of sulfur species. As a result, a cell with a CoSe 2 /CoO-CNTs modified separator displays a high initial discharge capacity of 1573 and 910 mAh/g at 0.1 and 2C, respectively. Furthermore, a low decay rate of 0.070% per cycle can be obtained over 500 cycles at 2C. The results of this study suggest that the as-prepared CoSe 2 /CoO-CNTs is an effective modifier that can improve the performance of Li-S batteries for use in next-generation energy storage systems. This study provides fundamental insights into the rational design of Mott-Schottky catalysts for practical high-performance Li-S batteries. [ABSTRACT FROM AUTHOR]

Nanocarbons with single‐metal atoms (M‐SAs) have displayed considerable potential in various fields of application due to high free energy of M‐SAs and strong metal‐support interaction. However, the uniform dispersion of M‐SAs within the whole carbon matrix still remains a great challenge. Herein, Ni‐SAs are uniformly dispersed within hierarchically porous carbon nanoflowers (Ni‐SA/HPCF) via a spatial confinement of Ni ions within the periodic pores in metal‐organic frameworks (MOFs) with a subsequent carbonization process. The Ni‐SA/HPCF with abundant mesopores and an ultrahigh surface area (1137.2 m2 g−1) exhibits unexpected electromagnetic wave (EMW) absorption property with a minimal reflection loss of –53.2 dB and an effective absorption bandwidth of 5.0 GHz, while the filler ratio in the matrix is merely 10 wt.%. Density functional theory calculations and experimental results reveal that the uniformly dispersed Ni‐SAs break local symmetry of the electronic structure and increase electrical conductivity of host carbon matrix, thereby enhancing the EMW absorption properties. In addition, the unique 3D hierarchical porous morphology boosts the impedance matching property, which synergistically improves the EMW absorption performance of the Ni‐SA/HPCF. This study provides an efficient approach to uniformly disperse M‐SAs within hierarchically porous nanocarbons for EMW absorption and other potential applications. [ABSTRACT FROM AUTHOR]

We propose a new concept to excite the electrochemical reaction kinetics of heterostructures by constructing a dual electric field. A new ReS 2 /Nb 2 O 5 heterostructure of rhenium disulfide coupled to niobium oxide with a mutually compatible band structure and enriched oxygen vacancies was constructed. The unique heterostructure can facilitate the redistribution of charges to induce built-in electric fields and micro-localized electric fields, which endows it with excellent lithium-ion storage performance. [Display omitted] • A new concept for constructing the dual electric field effect based on heterostructure to excite lithium ion storage electrochemical activity is proposed. • ReS 2 /Nb 2 O 5 heterostructure electrode exhibits excellent capacity and ultra-long period stability in lithium ion storage. • The phase transition process of ReS 2 /Nb 2 O 5 heterostructure during the electrochemical reaction was revealed. Heterostructures with the electric field effect can excite the charge transfer kinetics of materials due to the driving force of the electric field. Herein, we report a new ReS 2 /Nb 2 O 5 heterostructure of rhenium disulfide coupled to niobium oxide with a mutually compatible band structure and enriched oxygen vacancies. The unique heterostructure can facilitate the redistribution of charges to induce built-in electric fields and microlocalized electric fields. As expected, the ReS 2 /Nb 2 O 5 heterostructure shows a superior lithium-ion reversible capacity of 805 mAh g−1 after 2400 h at 0.10 A g−1, and 414 mAh g−1 at 2.00 A g−1. In addition, in situ X-ray diffraction and ex situ X-ray photoelectron spectroscopy analysis reveal the phase transition process of the ReS 2 /Nb 2 O 5 heterostructure during the electrochemical reaction. This provides deeper insights into the construction of high-performance lithium-ion storage materials based on heterostructures with dual-electric field-driven charge transfer. [ABSTRACT FROM AUTHOR]

The increasingly serious electromagnetic radiation urgently call for high performance electromagnetic wave (EMW) absorbers. Hollow carbon nanostructures are promising for lightweight EMW absorbers. However, due to lack of sufficient polarization centers, the EMW absorption property of hollow carbon nanosturctures is still unsatisfactory. Herein, we develop a double-salt template method for fabrication of N, S-codoped graphitic carbon nanoframes (GF) that anchored on the graphene sheets (GS). The GFs in the sample (N, S-GF/GS) have a width of about 51 nm and a wall thickness of only 4.8 nm. Furthermore, the graphene plane in the GF is perpendicular to the graphene plane in the GS, leading to the formation of numerous interfaces between the graphene planes perpendicular to each other. Theoretical calculations indicate that the interfaces can induce the interfacial polarization loss, and the N, S co-doping can cause dipole polarization loss, both of which enhance the EMW absorption performance of the N, S-GF/GS. The minimal reflection loss and efficient absorption width of the N, S-GF/GS at a low filler ratio of 10 wt% are -45.64 dB at the matching thickness of 2.3 mm and 4.35 GHz with the thickness of 1.5 mm, respectively, superior to most of carbon-based absorbers. Our proposed method opens a promising way for high-performance EMW absorbers. [Display omitted] • A double-salt template method was proposed for fabricating N, S-codoped carbon nanoframes (GF) on graphene (GS). • The GFs have a width of about 51 nm and a wall thickness of only 4.8 nm. • The graphene planes in GF and GS are perpendicular to each other, leading to numerous interfaces. • The effective absorption bandwidth of the designed absorbers reached 4.35 GHz. • The mechanism about the synergisty of interface and N, S co-doping was uncovered. [ABSTRACT FROM AUTHOR]

Three−dimensional (3D) hierarchical nano−microstructures have shown unprecedented physicochemical properties. However, it still remains great challenge to construct well−defined architectures with 3D hierarchical feature. Herein, we develop an electrospinning technique followed by a high−temperature carbonization process to fabricate N−doped carbon fibers (NCF) with N−doped carbon nanotubes (NCNTs) vertically grown on the surface of NCF using the Fe species as catalysts. In the 3D hierarchical structures, the Fe 3 C nanoparticles (NPs) are embedded within NCF matrix, while the Fe NPs are encapsulated within NCNT. Due to the unique structural feature, the as−prepared hierarchical structure exhibits excellent electromagnetic wave absorption performance with an absorption bandwidth of 4.0 GHz and a minimum reflection loss of −49.56 dB with a thickness as low as 1.50 mm. Experimental and theoretical studies indicate that the enhanced electromagnetic wave absorption performance of the hierarchical structure can be explained by the increased conduction loss induced by the introduction of metallic NPs and formation of 3D conductive networks, and the enhanced polarization loss caused by the additional interfaces and defects in the hierarchical structure. This work provides an efficient way to fabricate 3D architecture for high−efficiency electromagnetic wave absorption. [Display omitted] • The 3D hierarchical structure (Fe 3 C@NCF/Fe@NCNT) is synthesized. • In the structure, Fe 3 C NPs are embedded within NCF, while the Fe NPs are in NCNT. • Fe 3 C@NCF/Fe@NCNT exhibits good microwave absorption property with a low thickness. • The metals, interfaces and 3D networks are responsible for the absorption property. [ABSTRACT FROM AUTHOR]

Lithium metal is considered to be the best candidate for rechargeable batteries due to its unique advantages. But the instability and the uncontrollable dendrites of the lithium metal anode greatly limit its commercialization. In recent years, in order to obtain stable Li metal anodes, various three-dimensional (3D) current collectors have been proposed. However, for traditional 3D current collectors, its advantages in structure still need to be improved. Therefore, the 3D hierarchical Cu@Ag nanostructure consisting of Ag-decorated Cu nanowires grown on Cu foam as a current collector (denoted as 3D HCu@Ag) is well designed and successfully prepared. Cu nanowires were in situ grown on Cu foam to form a 3D hierarchical current collector to further increase the specific surface area and reduce the local current density, thus suppressing the formation of dendrites. Ag nanoparticles were in situ grown on the surface of Cu nanowires by displacement reaction, which can reduce the overpotential of lithium deposition. Under the synergistic effect of optimal structure and Ag surface modification, 3D HCu@Ag exhibits extremely excellent performance. As a result, the Li-3D HCu@Ag symmetrical cell exhibits a lifetime of 1500 h with a very low voltage hysteresis. More importantly, in practical application, the Li-3D HCu@Ag‖‖LFP full cell can cycle stably for 200 cycles at 1C and maintain an extremely high-capacity retention rate of 78.5%. The experiment results show that this design provides a new idea for the lithiophilic 3D current collector for stable lithium metal anode. [ABSTRACT FROM AUTHOR]

[Display omitted] Lithium–sulfur (Li–S) batteries are widely considered to be next-generation storage technologies due to their high energy density, low cost and non-toxicity. However, the soluble lithium polysulfides (LiPS) migrating to the anode side inevitably causes side reactions with the Li anode, resulting in severe corrosion of the Li anode, loss of active materials, and rapid battery failure. Therefore, it is necessary to develop effective strategies to avoid LiPS exposure to Li anodes. Herein, a stable UiO-66-ClO 4 /PDMS (PDUO-Cl) biomimetic protective layer is rationally constructed by the drip coating method. The PDUO-Cl protective layer can effectively suppress the side reaction of Li metal with LiPSs/electrolyte and homogenize the Li+ flux, thus avoiding corrosion of the Li metal anode. As a result, the symmetric cell with the PDUO-Cl protective layer delivers a stable cycle performance greater than 1400 h under a current density of 0.5 mA cm−2. The Li–S batteries with a PDUO-Cl protective layer still show relatively better rate performance and cycling stability (69% after 100 cycles at 0.1 C). This work provides new insights into the design of protective strategies for Li anodes in Li–S batteries. [ABSTRACT FROM AUTHOR]

It is highly desirable for electromagnetic wave (EMW) absorbers to have a low high filler ratio in matrix and low matching thickness. Herein, atomically dispersed Mn sites are introduced into N-doped carbon nanotubes (Mn−N x /NCNT) to this aim. Structural characterizations indicate that the as-fabricated Mn−N x /NCNT exhibits tubular morphology with a large surface area of 295.56 m2 g−1 and the Mn sites are atomically dispersed in the NCNT with a loading of 1.56 wt%. Benefiting from the unique structural advantages, Mn−N x /NCNT has excellent EMW absorption property, showing an effective absorption bandwidth of 4.15 GHz at a filler ratio of only 7% and a matching thickness of only 1.7 mm. The experimental measurements of electromagnetic parameters and density functional theory calculation results indicate that electronic structure and polarizability of the NCNTs are adjusted by the atomically dispersed Mn sites, leading to the increase in conduction and polarization losses of Mn−N x /NCNT, and thus in the EMW property. Our results demonstrate that hollow nanotubes containing metal single-atoms are potential EMW absorbers with a lightweight feature. [Display omitted] [ABSTRACT FROM AUTHOR]

The understanding of the relationships between the coordination configuration of single-atoms (SAs) and their properties remains a great challenge. In this manuscript, a facile method is developed to construct Fe-SAs on onion-like nitrogen-doped nanocarbons supported by graphene (ONCG). In contrast to the symmetrical planar Fe–N4 moieties, the Fe-SAs coordinated with N atoms are located above the plane of the curved graphene and exhibited antenna-like structures. The ONCG with non-planar Fe–N4 moieties possesses greatly increased dielectric loss property compared to their counterparts with symmetrical planar Fe-SAs. In-depth theoretical calculations reveal that the unique geometric structure of the non-planar Fe-SAs improves both conduction and polarization losses significantly, which is attributed to the increased dielectric property. The increased dielectric property endows Fe-SAs@ONCG with an excellent electromagnetic wave absorption at a low filler ratio of 10 wt. %. Our results describe an efficient way for the development of non-planar SAs for dielectric applications. [ABSTRACT FROM AUTHOR]

In 2 − x Ga x O 3 (ZnO) m are reported to exhibit an extremely high field-effect mobility, and therefore considered as the potential channel materials for transparent field-effect transistor. To gain a deep insight into the high mobility of In 2 − x Ga x O 3 (ZnO) m , the effective electron mass, which is inherently related to the mobility of charge carriers as well as the density of states, is investigated by valence electron energy-loss spectroscopy. The effective electron masses in InGaO 3 (ZnO) 3 nanobelts with the incident electron beam along the c axis and < 11 2 - 0 > are determined as 0.130 m 0 and 0.132 m 0 , respectively. These results critically checked by a comparison with calculated values and values measured by others. It not only well validates the results acquired from theoretical investigations, but also shed a new light on the isotropy of the effective electron mass in InGaO 3 (ZnO) m . [ABSTRACT FROM AUTHOR]

• Sufficient internal cavities of nanosphere improves impedance matching properties. • The multi-component heterostructure of Fe 3 O 4 /FeS x enhances interfacial polarization. • Fe 3 O 4 /FeS x nanospheres have optimal structural integrity and crystallinity at 400°C. • Hollow Fe 3 O 4 /FeS x nanospheres and graphene aerogel improve lightweight properties. • The RL and EAB of the synthesized materials are -43.03 dB and 4.24 GHz, respectively. The fabrication of materials featuring hollow structures or multi-component heterostructures effectively enhance the performance of electric/magnetic loss and improve the impedance matching properties of absorbers. In this work, by precisely controlling the sulfidation temperature at 400°C and incorporating rGO, we successfully obtained Fe 3 O 4 /FeS x -rGO aerogel materials with exceptional structural integrity and crystallinity. The electromagnetic parameter analysis and calculation confirm the enhancement of impedance matching, interface polarization, electrical conductivity, and dielectric loss capability of the hollow structure and multi-interface heterostructure; while computer simulation technology results verify the effective attenuation capability of the absorber for electromagnetic energy under practical application conditions. As a result, the reflection loss of Fe 3 O 4 /FeS x -rGO reach −43.03 dB at a thickness of only 2.0 mm and the effective absorption bandwidths is 4.24 GHz at a thickness of 1.6 mm. This multifactorial synergistic enhancement mechanism provides a new idea for the design and preparation of high-performance electromagnetic wave absorbing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

The systematic design of morphology and structure plays a significant role in enhancing the physicochemical properties of functional materials. In this work, short carbon nanorod-grafted magnetic N-doped carbon nanocage (FeCoNi@NC) was prepared using FeCoNi layered double hydroxide (LDH)/metal organic frameworks (MOFs) as precursor. Herein, a multi-level hollow nanocage was synthesized by hydrothermal method, in which nanorods were formed on the surface of the hierarchical structure, and after annealing, an N-doped hollow nanocage with short carbon nanorod-grafted was formed. Due to its unique hollow and hierarchical interfaces, the optimal FeCoNi@NC exhibits highly efficient electromagnetic wave absorption (EWA). At 14.32 GHz, the minimum reflection loss (RL min) reach −54.4 dB, while the effective absorption bandwidth (EAB) is over a wide range of 5.28 GHz, corresponding to a thickness of 1.5 mm. The outstanding ability to absorb electromagnetic waves is due to the hierarchical and hollow characteristics, which increase dielectric and conductive losses, while also optimizing impedance matching. The study presents a highly effective approach to fabricate hierarchical and hollow nanostructures with short nanorods, aiming to enhance the efficiency of EWA. [Display omitted] • Short carbon nanorod-grafted N-doped carbon nanocages were prepared. • The effective absorption bandwidth of the hierarchical nanocages reached 5.28 GHz. • The hierarchical and hollow features leaded to enhanced microwave absorption. [ABSTRACT FROM AUTHOR]

A novel three-dimensional graphene aerogel–ZnO spheres composite has been synthesized via a simple solvothermal method. The three-dimensional graphene exhibits interconnected macroporous networks and the ZnO spheres featured a size of 0.5–1 μm are anchored homogeneously on the surface of graphene layers. When being used as gas sensors for detection of NO 2 , the porous graphene–ZnO composite achieves a higher response and fast response/recovery behavior at room temperature effectively (RT). The enhancement of the sensing response is mainly attributed to the improved conductivity, the 3D porous structure of graphene and the interaction between p-type graphene and n-type zinc oxide. The sensing mechanism of the composite is also discussed. [ABSTRACT FROM AUTHOR]

Metal-organic frames derived magnetic nanostructures have potential applications in various fields. However, the magnetic particles in the derivatives are frequently agglomerated, limiting their physicochemical properties. Herein, we cross CoZn-MOF particles through ultra-long MnO 2 nanowires (MnO 2 @CoZn-MOF) as precursor for high-performance functional materials. After the carbonization of the MnO 2 @CoZn-MOF, MnO 2 nanowires were transformed into MnO nanowires coated with N -doped carbon layer (MnO@CN), while the CoZn-MOFs were converted into N -doped carbon polyhedron particles encapsulated with Mn 3 Co 7 alloy nanoparticles (Mn 3 Co 7 @CN), leading to the formation of hierarchically pearl necklace-like nanostructure (CoMn@CN). The magnetic Mn 3 Co 7 @CN nanoparticles are separated uniformly along one-dimensional MnO@CN nanowires, and thus the self-agglomeration of magnetic nanoparticles is avoided efficiently. As a result, the CoMn@CN exhibits excellent electromagnetic wave absorption property with an effective absorption bandwidth of 5.24 GHz as the matching thickness is only 2.0 mm. Experimental results and theory calculations indicate that the improved conductive loss and dielectric relaxation loss caused by abundant heterointerfaces and the electronic interaction between Co and Mn atoms are responsible for the excellent electromagnetic wave absorption performance. Our strategy provides an efficient way for the synthesis of high-performance MOFs-derived nanostructures. [Display omitted] [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have the potential to become the future energy storage system, yet they are plagued by sluggish redox kinetics. Therefore, enhancing the redox kinetics of polysulfides is key for the development of high-energy density and long-life Li–S batteries. Herein, a Ketjen Black (KB)/V2CTX modified separator (KB/V2CTX-PP) based on the catalytic effect in continuous solid-to-liquid-to-solid reactions is proposed to accelerate the conversion of sulfur species during the charge/discharge process in which the V2CTX can enhance the redox kinetics and inhibit polysulfide shuttling. The cells assembled with KB/V2CTX-PP achieve a gratifying first discharge capacity of 1236.1 mA h g−1 at 0.2C and the average capacity decay per cycle reaches 0.049% within 1000 cycles at 1C. The work provides an efficient idea to accelerate redox conversion and suppress shuttle effects by designing a multifunctional catalytic separator. [ABSTRACT FROM AUTHOR]

The inferior hydrogen evolution reaction (HER) catalytic performance of MoS 2 can be attributed to its small edge ratio, large inert substrate surface, and poor electrical conductivity, while the multiple strategies are expected to be employed simultaneously to modulate the electronic structure of MoS 2 and yield catalysts with superior HER catalytic performance. Here, we report a MoS 2 containing a 1 T phase with expanded layer spacing and construct it as a heterostructured material with MoO 2 (MoO 2 @E-MoS 2). Specifically, the presence of the 1 T phase and expanded layer structure of MoS 2 can enhance electrode conductivity, increase active site exposure, promote H 2 O adsorption, and optimize the Gibbs-free energy of hydrogen. The constructed heterostructure can modulate the electronic structure of the catalyst, enhance electron transfer at the interface, elevate water adsorption energy, and reduce the hydrogen reaction energy barrier. Moreover, density functional theory calculations indicate that the S site of MoS 2 in this catalyst exhibits a higher affinity for H 2 O adsorption, while the Mo site demonstrates a greater capacity for H* adsorption/desorption. Ultimately, MoO 2 @E-MoS 2 shows low overpotentials of 93 and 99 mV at a current density of 10 mA cm−2, as well as exceptional long-term stabilities exceeding 70 and 130 h at current densities ranging from 10 to 30 mA cm−2 in acidic and alkaline media, respectively. [Display omitted] • A heterogeneous is built with MoO 2 in the inner layer and MoS 2 in the outer layer. • The mixed 1 T/2 H phase of MoS 2 exhibits an expanded layer spacing of 0.93 nm. • The above strategies accelerate the HER thermodynamic and kinetic processes. • DFT reveal that the S and Mo sites are favor of H 2 O and H adsorption, respectively. • The catalyst has superior HER ability and durability in acidic and alkaline media. [ABSTRACT FROM AUTHOR]

Mn‐based oxides have sparked extensive scientific interest for aqueous Zn‐ion batteries due to the rich abundance, plentiful oxidation states, and high output voltage. However, the further development of Mn‐based oxides is severely hindered by the rapid capacity decay during cycling. Herein, a two‐step metal–organic framework (MOF)‐engaged templating strategy has been developed to rationally synthesize heterostructured Mn2O3–ZnMn2O4 hollow octahedrons (MO–ZMO HOs) for stable zinc ion storage. The distinctive composition and hollow heterostructure endow MO–ZMO HOs with abundant active sites, enhanced electric conductivity, and superior structural stability. By virtue of these advantages, the MO–ZMO HOs electrode shows high reversible capacity, impressive rate performance, and outstanding electrochemical stability. Furthermore, ex situ characterizations reveal that the charge storage of MO–ZMO HOs mainly originates from the highly reversible Zn2+ insertion/extraction reactions. [ABSTRACT FROM AUTHOR]

Mn‐based oxides have sparked extensive scientific interest for aqueous Zn‐ion batteries due to the rich abundance, plentiful oxidation states, and high output voltage. However, the further development of Mn‐based oxides is severely hindered by the rapid capacity decay during cycling. Herein, a two‐step metal–organic framework (MOF)‐engaged templating strategy has been developed to rationally synthesize heterostructured Mn2O3–ZnMn2O4 hollow octahedrons (MO–ZMO HOs) for stable zinc ion storage. The distinctive composition and hollow heterostructure endow MO–ZMO HOs with abundant active sites, enhanced electric conductivity, and superior structural stability. By virtue of these advantages, the MO–ZMO HOs electrode shows high reversible capacity, impressive rate performance, and outstanding electrochemical stability. Furthermore, ex situ characterizations reveal that the charge storage of MO–ZMO HOs mainly originates from the highly reversible Zn2+ insertion/extraction reactions. [ABSTRACT FROM AUTHOR]

Abstract: Using transmission electron microscopy-related techniques, we have compared the degradation behaviors of several different types of ZnS nanostructures, including the ZnS nanosheets synthesized by hydrothermal method (with different oxygen impurity concentration) and ZnS nanobelts grown using thermal evaporation. We have identified that displacement damage, sputtering, and oxidation mechanisms exist during the electron irradiation process. While oxidation of the nanostructure is always observed, displacement damage appears to be the dominant mechanism contributing to the final structural collapse of ZnS nanosheets (synthesized via hydrothermal methods), but sputtering mechanism becomes critical in changing the surface roughness of the ZnS nanobelts (grown by thermal evaporation). The specific damage mechanisms of these nanomaterials disclose that different synthesis process results in different structure quality (particularly impurity related interior defects) of the ZnS nanostructures, which determines their specific degradation behaviors under the electron beam irradiation. [ABSTRACT FROM AUTHOR]

A simple and low-cost technique was developed to produce unique SrWO4 and WO3 hollow spheres. The SrWO4 hollow spheres were prepared via a precipitation reaction between SrCl2 and Na2WO4 in the presence of polymethacrylic acid, and the synthesis of WO3 spheres used the as-prepared SrWO4 hollow spheres as both precursors and templates. After soaking in HNO3 and calcinations, the SrWO4 were completely transformed into WO3 while the hollow structures were perfectly retained. The “polymer-cation template” model was proposed to describe the formation of the SrWO4 hollow spheres. This technique is feasible in fabricating other inorganic hollow-structured materials. [ABSTRACT FROM AUTHOR]

Reasonable structure design of an absorber is important to its microwave absorption property. Herein we design a "non-standard" yolk-shelled nanostructure with a morphology mediated between core-shelled and yolk-shelled structures using Ni x S y sphere as yolk and N, S-codoped carbon as shell (n-Ni x S y @NSC). The n-Ni x S y @NSC possesses merits of both core-shelled and yolk-shelled nanostructures, resulted in its excellent microwave absorption performance. The optimal n-Ni x S y @NSC has a minimal reflection loss of −37.2 dB as the matching thickness is only 1.5 mm, superior to that of the bared NiS 2 sphere and previously reported absorbers with similar structure and composition. The experimental results and density functional theory calculations indicate that the enhanced microwave absorption performance of the n-Ni x S y @NSC is attributed to the increased electrical conductivity and interfacial polarization relaxation as well as the improved impedance matching feature. Our results highlight an efficient strategy for design and fabrication of high-performance microwave absorbers. [Display omitted] • A strategy for Ni x S y @NSC mediated between core and yolk-shelled structure is proposed. • The Ni x S y @NSC has the merits of both core-shelled and yolk-shelled structure. • The Ni x S y @NSC exhibits good microwave absorption property with a low thickness. [ABSTRACT FROM AUTHOR]

Cost-effective electrocatalysts are imperative to the large-scale hydrogen evolution reaction. Herein, 1T/2H–MoSe2/Ti3C2 composites are integrated via a hydrothermal method by taking advantage of the tunable phases of MoSe2 and high conductivity of Ti3C2. Consequently, the 1T/2H–MoSe2/Ti3C2 composites exhibit an optimal overpotential of 150 mV at 10 mA cm−2, a low Tafel slope of 90 mV dec−1, and a steady catalytic activity for over 30 h in an alkaline environment. The improved HER performances can be ascribed to the introduction of the Ti3C2 support in a proper proportion, which not only makes the charge transfer process more convenient but also helps the dispersion of MoSe2. Furthermore, the formation of MoSe2/Ti3C2 heterogeneous interfaces and the synergistic effects stemming from the intimate interactions between the individual components ultimately boost the H2O dissociation in the Volmer step. This study indicates that Ti3C2 is an ideal conductive support for improving HER catalytic activity, and paves a new way for other transition metal selenides and MXenes to build highly efficient HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Considering serious exhausted non-renewable energy resources and electromagnetic radiation pollution issues, it is quite urgent to exploit multifunctional material for realizing both the conversion sustainable energy sources and protection of electromagnetic radiation pollution. Herein, we develop a facile and high-yield preparation route to fabricate a multifunctional material consisted of CoFe alloy nanoparticles encapsulated in nitrogen doped carbon nanotubes arrays grown on both sides of reduced graphene oxide (CoFe@N-CNT/rGO). CoFe@N-CNT/rGO displays excellent properties in the field of rechargeable Zn-air battery and electromagnetic wave absorption. CoFe@N-CNT/rGO shows bifunctional electrocatalytic performances toward oxygen reduction reaction and oxygen evolution reaction, favorably comparable to that of commercial catalysts (Pt/C and IrO 2). Furthermore, the assembled liquid and all-solid-state rechargeable Zn-air batteries with CoFe@N-CNT/rGO as air cathode display good charging–discharging performance. As electromagnetic wave absorbing material, CoFe@N-CNT/rGO shows the minimal reflection loss of −33.2 dB at 13.3 GHz, superior to reported carbon-based electromagnetic wave absorbing materials. Based on excellent electromagnetic absorption performance, electromagnetic energy conversion device is designed to realize reasonable utilization and conversion of the absorbed electromagnetic energy. These encouraging results lay a solid foundation for development the multifunctional material and provide an effective strategy for simultaneously solving energy crisis and electromagnetic radiation problems. [Display omitted] • 3D rGO-supported N-doped CNT arrays (N-CNT/rGO) were fabricated by a facile method. • The N-CNT/rGO has multifunctionality for catalyzing ORR and OER and absorbing EMW. • The ORR activity of N-CNT/rGO is comparable to that of the commercial Pt/C. • EMW absorption property of N-CNT/rGO is outperforms most of carbon-based absorber. • The model device for reusage of waste electromagnetic energy is designed. [ABSTRACT FROM AUTHOR]

The lithium–sulfur (Li–S) battery is an appealing choice for the next-generation high-energy-density energy storage systems. However, side reactions between lithium polysulfides (LiPSs) and Li metal anode cause the growth of Li dendrites, loss of active materials, and safety issues, which severely hinders the practical application of Li–S batteries. Constructing a protection layer on the surface of Li anode is an effective strategy to shield LiPSs and regulate lithium uniform deposition in Li–S batteries. Herein, we design and fabricate a lithiated Nafion protective layer to alleviate the side reactions between LiPSs and the Li anode and guide uniform deposition of Li, in which, their mechanism is investigated. The optimal protective layer effectively protects the Li anode from the detrimental side reactions, which boosts the stability of the Li anode. Li–Li and Li-stainless steel cells with 4 M [S] Li 2 S 8 electrolyte can last for more than 400 cycles and 100 cycles at current density of 1 mA cm−2. A Li–S full cell also exhibits a high reversible capacity of 791.5 mA h g−1 after 250 cycles at 0.5 C. This work reveals the vital role of the artificial protective layer in enhancing the stability of the Li anode in Li–S batteries. Image 1 • Nafion protective layer was explored to shield polysulfide and regulate Li deposition. • The vital role of Nafion layer has been revealed in enhancing the life of Li anode. • The Li–S cell based on Nafion modified Li anode exhibits a high reversible capacity. [ABSTRACT FROM AUTHOR]

The application of lithium metal anodes for practical batteries is still impeded by safety issues and low Coulombic efficiency caused mainly by the uncontrollable growth of lithium dendrites. Herein, two types of free‐standing nitrogen‐doped amorphous Zn–carbon multichannel fibers are synthesized as multifunctional hosts for lithium accommodation. The 3D macroporous structures endow effectively reduced local current density, and the lithiophilic nitrogen‐doped carbon and functional Zn nanoparticles serve as preferred deposition sites with low nucleation barriers to guide uniform lithium deposition. As a result, the developed anodes exhibit remarkable electrochemical properties in terms of high Coulombic efficiency for more than 500 cycles at various current densities from 1 to 5 mA cm−2, and symmetric cells show long‐term cycling duration over 2000 h. Moreover, full cells based on the developed anode and a LiFePO4 cathode also demonstrate superior rate capability and stable cycle life. [ABSTRACT FROM AUTHOR]

The application of lithium metal anodes for practical batteries is still impeded by safety issues and low Coulombic efficiency caused mainly by the uncontrollable growth of lithium dendrites. Herein, two types of free‐standing nitrogen‐doped amorphous Zn–carbon multichannel fibers are synthesized as multifunctional hosts for lithium accommodation. The 3D macroporous structures endow effectively reduced local current density, and the lithiophilic nitrogen‐doped carbon and functional Zn nanoparticles serve as preferred deposition sites with low nucleation barriers to guide uniform lithium deposition. As a result, the developed anodes exhibit remarkable electrochemical properties in terms of high Coulombic efficiency for more than 500 cycles at various current densities from 1 to 5 mA cm−2, and symmetric cells show long‐term cycling duration over 2000 h. Moreover, full cells based on the developed anode and a LiFePO4 cathode also demonstrate superior rate capability and stable cycle life. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have emerged as one of the most promising energy storage solutions. However, its commercial application still faces a significant challenge: the sluggish redox reaction kinetics of the reversible lithium polysulfide (LiPS) conversion process. The strategic design of cathode structures and electrocatalysts can help accelerate polysulfide conversion. In this study, systematic density functional theory (DFT) calculations predict that the incorporation of platinum (Pt) nanoparticles, as a model electrocatalyst, into biomass carbon materials can effectively promote the bidirectional conversion of polysulfides. Detailed kinetic analyses reveal that Pt-doped biomass carbon materials possess exceptional electrocatalytic abilities for Li 2 S nucleation and dissociation. These findings are further elucidated by ex situ X–ray photoelectron spectroscopy measurements, elucidating the bidirectional mechanism of Pt. The sulfur cathode delivers a remarkable specific discharge capacity of 1386.9 mAh g–1 at 0.1 C. Even more impressive is its potential for practical applications, exemplified by a high initial capacity of 1218.7/1015.3 mAh g−1 and excellent cycling stability under a high sulfur loading of 4.5/7.5 mg cm−2, which achieved substantial capacity retention (83.9/81.1%) after 100 cycles. This bidirectional electrocatalysis, achieved through the synergy of metal with biomass carbon materials, presents an attractive approach for advancing Li–S systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1D porous nanocarbons containing atomically dispersed Zn atom is prepared. • Absorption bandwidth of 5.89 GHz at 2.0 mm was achieved by the 1D absorber. • DFT calculation showed that Zn doping greatly enhanced the absorption property. • Selective absorption in a wide frequency region was achieved by the 1D carbon. Carbon fibers with low density, high stability and unique structural characteristics are a huge potential electromagnetic wave absorber. However, it is difficult to achieve wide-band absorption of the carbon fibers due to their impedance mismatching and limited loss factors. Herein, we develop a facile method to fabricate Zn,N-codoped carbon particles/carbon fiber (N,Zn-PNP/NCF). The Zn,N-codoped strategy can cause the distortion of electron clouds of C atoms and the generation of defect sites, which improve the electromagnetic wave absorption performance of carbon fibers. As a result, the optimal N,Zn-PNP/NCF show excellent absorption property with an effective absorption bandwidth of 5.89 GHz at the thickness of 2.0 mm, which is significantly superior to the ordinary N-doped carbon material and most of reported carbon-based absorbers. Theoretical calculations and the experimental results suggest that the Zn,N-codoping along with the interfaces between carbon particles and carbon fibers can effectively enhance the polarization loss capability of carbon fibers due to the charge redistribution caused by the Zn and N heteroatoms. Besides, based on the dielectric characteristic of the optimal N,Zn-PNP/NCF, a pressure response absorber (PSA) is designed, which can realize the selective absorption in the wide frequency region. [ABSTRACT FROM AUTHOR]

• Domain III of EGFR was successfully expressed as the immunogen and had high affinity with anti-EGFR antibody H11. • A novel anti-EGFR nanobody (Nb AS32611) was screened through phage display and epitope binning. • The structure of AS32611 was built through homology modeling. • The epitope and paratope of AS32611 were predicted by molecular docking to provide the structural basis for multi-epitope therapy. Since EGFR is an important and effective target for tumor therapy in the clinic. Several monoclonal antibodies and nanobodies were proved to target domain III of EGFR. Regarding the increased attention on nanobodies, the present study aimed to generate nanobodies specifically against domain III. After camel immunization, a gene repertoire of sdAb fragments with a diversity of 3×109 clones was produced. Following the construction of two sdAb phage display libraries, the successful epitope binning was carried out to identify the nanobody with the designated epitope. Modelling of the identified nanobody and molecular docking studies illustrated the paratope and epitope. Docking analysis revealed that the paratope focused on CDR2 loop of the identified nanobody. The identified nanobody potently cover part of the epitope of Matuzumab and Nb 9G8, which indicated that it blocked EGFR by preventing dimerization of the receptors. [ABSTRACT FROM AUTHOR]