Co3O4 emerges as a promising candidate to replace commercial graphite anodes in lithium-ion batteries owing to its high theoretical specific capacity of 890 mAh g- 1, natural abundance, and facile synthesis. However, its practical application is currently limited by significant volume variation during lithiation/delithiation cycles and low electrical conductivity. To address these limitations, this study proposes a novel low-temperature strategy for Co3O4 deposition integrateing with hydrothermal growth of MoS2 on balsa wood-derived porous carbon (BioC) to fabricate a carbon-based MoS2/Co3O4 composite. Specifically, BioC serves as a conductive scaffold where twodimensional MoS2 nanosheets grow uniformly via a hydrothermal approach. Subsequently, sheet-like Co3O4 nanoparticles form onto the MoS2 layers through a low-temperature alternating immersion process. This forms a well-integrated heterostructure that enhances electron transport efficiency, and the resulting composite exhibits exceptional electrochemical performance. The C@MoS2/Co3O4-BioC composite delivers an initial discharge capacity of 1709.9 mAh g- 1 at 50 mA g- 1 and retains over 83.8% of its capacity after 100 cycles at 500 mA g- 1. Additionally, the electrode demonstrates remarkable rate capability over a current density range of 50 to 1000 mA g- 1, significantly outperforming pure MoS2 or Co3O4 electrodes. This work provides a feasibly strategy for designing high-performance anode materials for advanced LIBs.

Sluggish desolvation kinetics at the interface pose a critical bottleneck for hard carbon (HC) anodes, severely limiting their rate capability and fast-charging performance. This study addresses this fundamental challenge by constructing a graphitic carbon nitride (g-C3N4) nanosieve to establish an active, geometry-regulated interphase. The proposed mechanism relies on an adsorption-capture-promotion process, whereby pyridinic nitrogen sites facilitate the spontaneous desolvation of Na+ through strong electrostatic interactions. Theoretical calculations reveal that these sites release an adsorption energy of 3.41 eV, which overcompensates for the 1.39 eV desolvation enthalpy to convert hindered ion transfer into a spontaneous process. Multi-scale characterization identifies a self-optimizing amorphization-to-crystallization transition of the g-C3N4 layer and solid electrolyte interphase (SEI) during cycling. This structural evolution sustains a thin and highly crystalline interface, which reduces charge transfer resistance to ensure long-term stability. The optimized 10 wt.% g-C3N4-coated HC (HC@10%CN) anode delivers 145 mAh g-1 at 8 A g-1 and demonstrates 94.7% capacity retention after 500 cycles at 1 A g-1. The full cell paired with Na3V2(PO4)3 achieves stable reversibility at 6 A g-1 to validate the practical potential of this configuration. This work establishes active interfacial adsorption as a universal design framework for high-rate energy storage.

The growing demand for energy and the urgency of mitigating environmental degradation and achieving carbon neutrality have created a critical need for renewable energy solutions. Photocatalysis offers a promising route to convert abundant solar energy into clean fuels, but conventional semiconductor photocatalysts only absorb UV light and partial visible light. One strategy to overcome this spectral limitation is to integrate upconversion materials that convert low-energy near-infrared photons into higher-energy visible or UV photons, effectively broadening the light absorption range of photocatalytic systems. This review systematically compares diverse photon upconversion approaches, both lanthanide-based (rare-earth phosphors) and emerging non-lanthanide mechanisms such as defect-mediated sequential excitations, two-photon absorption, and organic triplet-triplet annihilation upconversion, and examines their integration with semiconductor photocatalysts. Structural design strategies (e.g., core-shell nanostructures) and defect engineering are analyzed to illustrate how they improve light harvesting and charge separation. How these upconversion-enhanced composites significantly boost solar-driven reactions is discussed didcussed, notably water splitting for hydrogen production, CO 2 reduction, and pollutant degradation. Finally, key challenges and future directions are highlighted, including enhancing upconversion quantum efficiency, developing rare-earth-free upconversion systems, and optimizing interface engineering to maximize energy transfer and overall photocatalytic performance.

Molybdenum disulfide (MoS2), a highly promising two-dimensional transition metal dichalcogenide (TMD), exhibits substantial theoretical capacity as a lithium-ion host, positioning it as a leading candidate for lithium-ion battery (LIB) anodes. Nevertheless, its inherently fragile and low-conductive layered architecture imposes limitations on rate performance and cycling stability, resulting in poor reaction reversibility and challenges in realizing its theoretical capacity. The combination of disulfide heterostructures and biochar is considered an effective strategy to address the aforementioned issues. The disulfide heterostructure engineering has shown that built-in electric fields at TMD interfaces can accelerate Li+ diffusion by 3-5 fold, while biochar-based composites have demonstrated exceptional structural stability due to their hierarchical porosity. Herein, C@WS2-MoS2 heterostructures anchored on a biochar (BioC) framework were constructed by introducing WS2 on 2D MoS2 and doping it with carbon. The optimized C@WS2-MoS2-BioC composite delivers an ultra-high capacity of 884.4 mAh g-1 at 0.1 A g-1, retains 473.4 mAh g-1 even at 5.0 A g-1, and exhibits a high reversible capacity of 514.4 mAh g-1 after 2000 cycles at 1.0 A g-1. This work bridges recent advancements in heterostructure design and biomass-derived materials, offering a scalable strategy for high-performance LIB anodes.

Lithium titanate (Li4Ti5O12, LTO) used as a "zero-strain" anode material in lithium-ion batteries (LIBs) is wellknown for its long cycle life. However, its practical application is limited due to the low specific capacity (170 mAh g-1). In this research, we optimized the electrode composition by incorporating micrometer-sized phosphorus niobium oxides (PNb9O25, PNO) to prepare blended anode electrode, thereby significantly improving the capacity, stability, and volumetric energy density. PNO serves as a mixed ionic and electronic conductor (MIECs), aiding in the reduction of polarization and enhancement of the tap density. Consequently, the LTO/PNO (20 %) blended anode with 90 % active material content are able to stably deliver 93 % capacity retention at 4000 mA g-1 after 4000 cycles and high volumetric energy density of 668 Wh L-1 at 100 mA g-1. Our findings underscore the significance of industrialization methods, emphasizing the need for targeted modifications to enhance cell performance.

Potassium ion batteries (PIBs) have attracted increasing attention due to their inexpensive elemental potassium resources and excellent theoretical electrochemical properties. Two-dimensional metal sulfides exhibit a high specific capacity as potassium ion hosts, but the high diffusion barriers for potassium ions lead to a poor reversibility of the reaction and make the theoretical capacity difficult to achieve. Here, the sulphide MoS2 was introduced into WS2 nanosheets to construct layered WS2/MoS2 heterostructures anchored on a biogenic carbon (BioC) framework. The MoS2 in the framework served as an anchoring site to stabilise the intermediate product KxSy and to increase the WS2 layer spacing. Interfacial electric fields and potassium ion migration channels with high conversion reversibility were also formed in the layered heterostructures. The results confirmed that the reversibility of the reaction and the potassium ion diffusion rate were improved. As a result, the WS2-MoS2-BioC electrode achieves high specific capacity and diffusion rate, with a reversible specific capacity of up to 517.1 mAh g- 1 at 0.1 A g- 1, and a three order of magnitude improvement in potassium ion diffusion performance compared to that of MoS2-BioC. This heterostructure design strategy provides ideas for the development of metal sulphide anodes for potassium ion batteries.

Improving the performance of electrode materials is a crucial step for enhancing the intrinsic safety of batteries, especially during high operating temperature conditions and rapid charge/discharge processes. The aggravation of side reactions caused by electro-thermal behaviors especially at high operating temperature is the main factor causing the instability of surface structure. In this work, we focus on the titanium-free, coarse-grained PNb9O25 (PNO) anode and enhance its electrochemical performance at an elevated temperature of 45 degrees C using a nitrogendoped carbon (N-C) surface modification strategy. The homogeneous N-C passivation layer provides favorable electronic conductivity and fast Li+ diffusion kinetics, significantly reducing chemical reactivity and improving the interfacial charge transfer capability. As a result, PNO@N-C demonstrates exceptional high-rate capacity retention (249 mAh g(-1) at 0.1 A g(-1) and 173 mAh g(-1) at 6 A g(-1) under 45 degrees C) and superior cycling stability, maintaining a high capacity of 147 mAh g(-1) after 1000 rapid charging cycles at a current density of 4 A g(-1) (similar to 20 C, 45 degrees C). This approach provides a practical strategy for further development of electrode materials for high-rate lithium-ion batteries operating at high temperatures.

The solid-electrolyte interface (SEI) formed by electrolyte decomposition allows Li+ transport while blocking electrons, thus stabilizing the electrochemical reaction. Its composition evolves during cycling, but its composition and stability can be optimized by surface modification. In this study, Li3PO4 nanoparticles are modified on the surface of SiOx/C anodes. Li3PO4 not only enhances the electronic conductivity of the SiOx/C anode but also contributes to the stability of the SEI by regulating the interface of the multiphase equilibrium in chemical reactions. The Li3PO4 modification improves the Li+ transport kinetics and enhances the interfacial conductivity, thereby enhancing the cycling stability and electrochemical performance of the anode. The cycling stability and rate capability of the modified SiOx/C anode are remarkably improved. Specifically, after 100 cycles at 2000 mA g-1, the capacity retention of SiOx/C@Li3PO4 reaches 430 mAh g-1 (78 %). Compared to the pristine SiOx/C (124 mAh g-1, 44 %), it shows an obvious performance improvement. Our study demonstrates that Li3PO4 effectively enhances the structural stability and electrochemical performance of the SiOx/C anode.

Maintaining the surface structure stability of LiCoO2 (LCO) during rapid charge-discharge processes (>5C) and under high-voltage conditions (>4.2 V) is challenging due to interfacial side reactions, cobalt dissolution, and oxygen redox activity at deeply delithiated states, all of which contribute to performance degradation. Herein, different from traditional surface coating methods, we report a water-mediated strategy that modifies the surface architecture of LCO, creating a passivating layer to inhibit surface degradation and enhance cycling stability under fast charging conditions. The surface etching of LCO by H2O is accompanied by a concurrent Li+/H+ cation exchange, which passivates surface oxygen with H+ ions, thereby enhancing both the hydrophobicity and structural stability. Consequently, the modified LCO exhibits superior capacity retention, which is 2.5 times that of the pristine LCO, after 100 cycles at a current density of 1000 mA g-1 (∼6C at 4.5 V). Even at an elevated temperature of 45 °C, it maintains impressive cycling stability at a current density of 500 mA g-1 (∼3C), as demonstrated in practical full-cell configurations. Investigation with multiple samples confirmed that the water-mediated strategy demonstrated broad applicability. We emphasize that the water-mediated modification of the surface architecture on cathode materials offers significant insights into enhancing the stability of high-energy-density lithium-ion batteries (LIBs).

Micron-silicon based material is a promising anode material for high performance lithium batteries due to its ultra-high specific capacity. However, the volume expansion exceeds 300% during charging and discharging, resulting in the collapse of the electrode structure and a rapid decline in electrochemical performance. Coating the surface of silicon-based materials with flexible ionic conductors is an effective method to maintain their high capacity and suppress swelling. Here, to further improve the electrochemical performance of silicon-based materials, we have deposited a titanate-type ionic conductor layer on a micron-sized silicon-carbon oxide (SiOX-C) material to synthesize the SiOX-C@TiOx(OH)y material. The TiOx(OH)y layer not only exhibits the elastic properties of a superpolymer to mitigate swelling strain, but also has a fast capacitance effect to improve its rate performance. In addition, the interfacial charge transport of SiOX-C@TiOx(OH)y is enhanced due to the structural diversity of the TiOx(OH)y layer. For the above mechanisms, the SiOX-C@TiOx(OH)y has a specific capacity of 278.3 mAh g-1 under high current of 3500 mA g-1. Meanwhile, the SiOX-C@TiOx(OH)y with the capacity retention of 67% is achieved at 2000 mA g-1 after 100 cycles.

Li+ insertion-induced structure transformation in crystalline electrodes vitally influence the energy density and cycle life of secondary lithium-ion battery. However, the influence mechanism of structure transformation-induced Li+ migration on the electrochemical performance of micro-crystal materials is still unclear and the strategy to profit from such structure transformation remains exploited. Here, an interesting self-optimization of structure evolution during electrochemical cycling in Nb2O5 micro-crystal with rich domain boundaries is demonstrated, which greatly improves the charge transfer property and mechanical strength. The lattice rearrangement activates the Li+ diffusion kinetics and hinders the particle crack, thus enabling a nearly zero-degeneration operation after 8000 cycles. Full cell paired with lithium cobalt oxides displays an exceptionally high capacity of 176 mA h g-1 at 8000 mA g-1 and excellent long-term durability at 6000 mA g-1 with 63% capacity retention over 2000 cycles. Interestingly, a unique fingerprint based on the intensity ratio of two X-ray diffraction peaks is successfully extracted as a measure of Nb2O5 electrochemical performance. The structure self-optimization for fast charge transfer and high mechanical strength exemplifies a new battery electrode design concept and opens up a vast space of strategy to develop high-performance lithium-ion batteries with high energy density and ultra-long cycle life.

Based on wave function linear addition principle of quantum mechanics, the incident wave function was decomposed into two sub-wave functions corresponding to transmission and reflection, and the non-zero initial phases of transmission and reflection were extracted from the two sub-wave functions when particle is not totally transmitted or reflected, which were commonly thought to be zero. Then, the analytical expressions of transmission and reflection phase time and corresponding lateral displacement were derived for a rectangular symmetric barrier structure model. The numerical results show that the relative deviation of the transmission phase time and lateral displacement caused by the non-zeros initial phase is up to 70% compared with the usual zero initial phase assumption for low incident energy and narrow barrier width.

Sodium–ion batteries (SIBs) are essential for large–scale energy storage attributed to the high abundance of sodium. Polyanion Na3V2(PO4)3 (NVP) is a dominant cathode candidate for SIBs because of its high-voltage and sodium superionic conductor (NASICON) framework. However, the electrochemical performance of NVP is hindered by the inherently poor electronic conductivity, especially for extreme fast charging and long-duration cycling. Herein, we develop a facile one-step in-situ polycondensation method to synthesize the three-dimensional (3D) Na3V2(PO4)3/holey-carbon frameworks (NVP@C) by using melamine as carbon source. In this architecture, NVP crystals intergrown with the 3D holey-carbon frameworks provide rapid transport pathways for ion/electron transmission to increase the ultrahigh rate ability and cycle capability. Consequently, the NVP@C cathode possesses a high reversible capacity of 113.9 mAh g−1 at 100 mA g−1 and delivers an outstanding high–rate capability of 75.3 mAh g−1 at 6000 mA g−1. Moreover, it shows that the NVP@C cathode is able to display a volumetric energy density of 54 Wh L−1 at 6000 mA g−1 (31 Wh L−1 for NVP bulk), as well as excellent cycling performance of 65.4 mAh g−1 after 1000 cycles at 2000 mA g−1. Furthermore, the NVP@C exhibits remarkable reversible capabilities of 81.9 mAh g−1 at a current density of 100 mA g−1 and 60.2 mAh g−1 at 1000 mA g−1 even at a low temperature of −15 °C. The structure of porous carbon frameworks combined with single crystal materials by in-situ polycondensation offers general guidelines for the design of sodium, lithium and potassium energy storage materials.

Titanium carbide (TiC)-based electrodes are attractive in supercapacitor due to their ultra-high density and pseudocapacitive charge storage mechanism. However, TiC films with horizontal alignment of flakes or random nanostructures limit the high rate of charge transfer and hinder the migration of ions to redox active sites. In this work, the TiC nanotubes and three-dimensional interconnected nanoflakes are synthesized by electrodeposition and carbothermal treatment of carbon nanotube (CNT) film and graphite, respectively. To study the capacitance mechanism of TiC nanotube-interconnected branch (NTIB) films, the in-situ Raman spectrums of the TiC-NTIB negative electrode during the charge/discharge processes in H2SO4 show that hydronium is bonded to the terminal O during discharge, and debonding occurs during charging. The integrated TiC NTIB electrode is capable of operating at rates faster than that of carbon, conductive polymers or transition metal oxides, but still delivers a specific capacitance of 273 F g(-1) at 10 A g(-1) after repeating 2000 cycles at current densities of 1, 3, 5 and 10 A g(-1). The symmetric supercapacitor composed of the TiC NTIB electrodes delivers an energy density of 64.4 Wh kg(-1) (at 892.3 W kg(-1)) and a power density of 9.5 kW kg(-1) (at 55.6 Wh kg-1), and a good cycle stability (approximate to 86.7% retention after 15,000 cycles). (C) 2021 Elsevier B.V. All rights reserved.

Developing high capacity solid-state super capacitors and exploring their storage mechanism is one of the ongoing scientific topics. Here a novel TiO2-carbon nanotube (CNT) electrode is prepared by electrochemical deposition of TiO2 nanostructures on the CNT film. In situ Raman spectroscopy showed that the ion transfer kinetics of 3D rutile-based TiO2 were mainly controlled by ion adsorption. Symmetric solid-state supercapacitors compose of two TiO2-CNT electrodes and H2SO4-polyvinyl alcohol gel electrolyte. The devices show a high energy density of 82.5 Wh kg(-1) and specific capacitance of 345.7F g(-1) at 1.0 A g(-1). Furthermore, the TiO2-CNT supercapacitor illustrates excellent cyclic stability with capacitor retention of 93.3% after 10,000 cycles, and a low leakage current of 9 mu A after 2 h. This may due to the matching of the diffusion path topology of the rutile-doped less anatase structure. These results demonstrate that the TiO2-CNT supercapacitor may bring new opportunities to the power supply of portable electronics in the future.

A novel flexible nanoarchitecture is fabricated via the facile electrophoresis of a reduced graphene oxide (rGO) network on carbon nanotube (CNT)-Fe3O4 film for supercapacitor electrode applications. The interconnected networks of graphene with large specific surface area (248.4 m(2) g(-1)) improve the diffusion of the electrolyte ions into the electrode. The resulting supercapacitor exhibits a high specific energy density of 36.7 Wh kg(-1), specific capacitance of 275.6 F g(-1) at a current density of 1 A g(-1) and excellent cyclic stability with only 7.1% loss of its initial specific capacitance after 10000 change-discharge cycles. These results suggest that such CNT-Fe3O4-rGO composite is very promising for next generation high-performance supercapacitors.

Flexible supercapacitors with high power densities and durability have shown enormous potential for use in portable electronics. In this study, we developed a high-performance supercapacitor by building a three-dimensional (3D) reduced graphene oxide (rGO) structure on a CNT-Fe3O4-PANI film. The porous rGO structure with a large surface area endows rGO-CNT-Fe3O4-PANI electrodes with excellent electrochemical properties, such as a specific capacitance of 414.5 F g(-1) at 1 A g(-1). Moreover, a symmetric supercapacitor device with rGO-CNT-Fe3O4-PANI electrodes demonstrated a remarkable cell performance, with an energy density of 60.8 Wh kg(-1), a power density of 45.2 kW kg(-1) and an excellent cycle life, indicating that the rGO-CNT-Fe3O4-PANI composite is a promising and novel energy storage electrode that can be used for fast and efficient energy storage. (C) 2019 Elsevier B.V. All rights reserved.

This paper reports enhancement of the electromagnetic (EM)-wave-absorbing capability of stretchable nanocomposites through the introduction of microbuckling. Three-dimentional composites are fabricated by laminating carbon nanotube films decorated with in situ grown Fe3O4 nanoparticles using a solvothermal process. The highly wavy morphology enhances the dispersion of EM-wave energy through multiple reflections and gives rise to higher active material content per unit area. The minimum reflection loss of −53.3 dB with a 8.1 GHz bandwidth is achieved for a three-layer buckled Fe3O4/carbon nanotube/poly(dimethylsiloxane) composite, which is superior to the performance of the corresponding unbuckled composite. The fundamental EM-wave absorption mechanism of the composite is discussed. This research has demonstrated microbuckling as a viable approach to fabricating stretchable, broad-bandwidth, and efficient EM-wave-absorbing composites.

A multi-layered composite with exceptionally high electromagnetic wave-absorbing capacity and performance stability was fabricated via the facile electrophoresis of a reduced graphene oxide network on carbon nanotube (CNT)-Fe3O4-polyaniline (PANI) film. Minimum reflection loss (RL) of -53.2 dB and absorbing bandwidth of 5.87 GHz (< -10 dB) are achieved, surpassing most recently reported CNT- and graphene-based absorbers. In particular, comparing to the original composites, the minimum RL and bandwidth (< -10 dB) maintains 82.5% and 99.7%, respectively, after 20 h charge/discharge cycling, demonstrating high environmental suitability.