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We report the fabrication of high-performance CNT-AC supercapacitor electrodes. CNTs are also added in the electrode preparation in this work because of high microporosity of activated carbon. The bigger ions can hardly be diffused and adsorbed onto the smaller micropores of activated carbon. The mesoporous nature of CNTs can enhance the ion adsorption through its unique and well-defined hollow core. The as prepared CNT-AC was then used as additive material to study the electrochemical properties of activated carbon based electric double layered supercapacitors (EDLCs). The physiochemical properties of CNT-AC were studied using scanning electron microscopy (SEM), Raman spectroscopic techniques, and transmission electron microscopy (TEM). Coin-type EDLC cells with two symmetrical carbon electrodes were using the synthesized carbon materials for the decrease of resistance. The electrochemical performance of the carbon electrodes was measured by galvanostatic charge/discharge and cyclic voltammetry methods. [ABSTRACT FROM AUTHOR]

It is crucial to control the structure and composition of composite anode materials to enhance the cell performance of such anode materials for lithium ion batteries. Herein, a biomimetic strategy is demonstrated for the design of high performance anode materials, inspired by the structural characteristics and working principles of sticky spider-webs. Hierarchically porous, sticky, spider-web-like multiwall carbon nanotube (MWCNT) networks are prepared through a process involving ozonation, ice-templating assembly, and thermal treatment, thereby integrating the networks with γ-Fe2O3 particles. The spider-web-like MWCNT/γ-Fe2O3 composite network not only traps the active γ-Fe2O3 materials tightly but also provides fast charge transport through the 3D internetworked pathways and the mechanical integrity. Consequently, the composite web shows a high capacity of ≈822 mA h g−1 at 0.05 A g−1, fast rate capability with ≈72.3% retention at rates from 0.05 to 1 A g−1, and excellent cycling stability of >88% capacity retention after 310 cycles with a Coulombic efficiency >99%. These remarkable electrochemical performances are attributed to the complementarity of the 3D spider-web-like structure with the strong attachment of γ-Fe2O3 particles on the sticky surface. This synthetic strategy offers an environmentally safe, simple, and cost-effective avenue for the biomimetic design of high performance energy storage materials. [ABSTRACT FROM AUTHOR]

The cover page of the journal related to composites prepared with pristine, oxidized, and surfactant treated multiwalled carbon nanotubes is presented.

The hierarchically porous, sticky spider‐web‐like composite anodes are inspired by the unique structure and work function of a natural spider‐web in a straightforward and artificial manner. In article number 1700331, Ho Seok Park and co‐workers report that the improved rate and cyclic capabilities are associated with the facilitated charge transfer and Li+ ion transport through the 3D internetworked pathways and the tight bonding onto the sticky functionalized surfaces. [ABSTRACT FROM AUTHOR]

In this study, we explore the efficacy of fluorine and nitrogen co-doped carbon nanotubes (F@N-CNT) as a novel surface modifier for lithium titanate (LTO) anodes in lithium-ion batteries (LIBs). The integration of F@N-CNT enhances the electrochemical properties of LTO anodes by improving electrical conductivity and facilitating lithium-ion diffusion., Electrodes modified with F@N-CNT exhibited significant improvements in capacity retention, achieving 71 % capacity retention over 200 cycles at 2 C and delivering energy capacities up to 162.9 mAh g−1 at 0.2 C, with an impressive high-rate performance of 74.8 mAh g−1 at 30 C. This study demonstrates that F@N-CNT effectively forms a conductive network within the LTO matrix, resulting in superior high-rate performance and stability. It presents a comprehensive analysis of the microstructural changes induced by co-doping and elucidates their impact on the electrochemical performance, providing valuable insights into the design of high-performance anodes for future energy storage applications. This approach not only addresses the current limitations of LTO anodes but also introduces a scalable strategy for enhancing the overall functionality of LIBs. [Display omitted] • Fluorine and nitrogen co-doped carbon nanotubes as conductive agent. • Dual-channel conductive system with line-to-point and line-to-line connections • Improved electrical connectivity and increased structural resilience of anode • Significant step forward in Li-ion battery technology. [ABSTRACT FROM AUTHOR]

We propose a facile route to fabricate carbon nanotube-activated carbon composite electrodes for supercapacitor applications. The crux of our approach lies in the use of softened pitch that becomes viscous at 110 °C and combines effortlessly with multi-walled carbon nanotubes, allowing a one-pot chemical activation at 900 °C. Meso/macroscale pores created by a bundle of the nanotubes can be infiltrated effectively by the softened pitch, increasing the apparent tap density with microporosity. This composite electrode leverages the high electron conductivity of percolated multi-walled carbon nanotubes and the large surface area of activated carbon, leading to high gravimetric (11.9 Wh/kg) and volumetric energy densities (10.4 Wh/L) at 1 mA/cm2. Our method substantially simplifies the preparation of carbon nanotube-activated carbon composite materials and can be an excellent strategy to obtain practical energy storage properties at a reduced processing cost. Image 1 [ABSTRACT FROM AUTHOR]

We report on a highly conductive CNT micro-spherical network for high-rate silicon anode materials prepared by one-pot spray drying for lithium-ion batteries. The anode material contains silicon nanoparticles bound to CNTs through a small amount of sucrose-derived carbon. The first charge and discharge capacities of the Si/CNT/C microsphere electrode are measured to be 3152 and 2302 mA h g −1 of the composite, respectively, at 0.1 A g −1 . The Si/CNT/C microsphere electrode exhibits an initial capacity of 1989 mA h g −1  at current density of 1.0 A g −1 and retains ∼70% of the initial capacity after 100 cycles. Even at a high current density of 10 A g −1 , the Si/CNT/C microsphere electrode exhibits a capacity of 784 mA h g −1 with a stable charge/discharge behavior. The superior rate capability of the Si/CNT/C microsphere composites can be attributable to the unhindered Li-ion transport through the highly conductive CNT buffer matrix, to which Si NPs are strongly bound by the sucrose-derived carbon. These salient results give further impetus to the study of CNTs for use as a buffer matrix to improve the rate capability of high-capacity electrode materials with large volume changes during charge storage. [ABSTRACT FROM AUTHOR]

[Display omitted] • Uniform LTO/CNT nanocomposite was easily obtained via mechanofusion. • The surface of LTO/CNT was fluorinated via a simple post-treatment with NH 4 F. • The degree of fluorination was easily controlled by adjusting the amount of NH 4 F. • The fluorinated-LTO/CNT nanocomposites showed excellent electrochemical performance. Lithium titanate (Li 4 Ti 5 O 12 , LTO) with a spinel structure has attracted considerable attention as a promising anode material for application in lithium-ion batteries (LIBs) with high stability and long cycle life. However, the rate characteristics of the battery deteriorate due to its low electronic conductivity. In this study, a uniform nanocomposite was easily obtained by complexing bulk LTO particles and carbon nanotubes (CNTs) via mechanofusion. Additionally, without using hazardous reagents, the surface of the LTO/CNT nanocomposites could be easily fluorinated via a simple post-treatment using ammonium fluoride (NH 4 F). It was demonstrated that the degree of fluorination of the LTO/CNT nanocomposites could be easily controlled by adjusting the amount of NH 4 F. The surface fluorinated-LTO/CNT nanocomposites, in which the main strategies for improving electrical conductivity were introduced simultaneously, showed excellent electrochemical performance as anodes for LIBs. In particular, the optimized surface fluorinated-LTO/CNT nanocomposites not only exhibited a high specific capacity of 170.2 mAh g−1 at 0.2 C, but also maintained a capacity of ∼140 mAh g−1 at a high rate of 20 C, which was almost 2.3 times higher than that of bulk LTO particles. [ABSTRACT FROM AUTHOR]