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Herein, highly transparent, flexible, and ultrathin piezocomposite, in which electrospun poly(vinylidene fluoride‐co‐trifluoroethylene) [P(VDF‐TrFE)] nanofibers (NFs) and aerosol‐synthesized single‐walled carbon nanotubes (SWCNTs) are embedded in elastomer matrix, is fabricated. The P(VDF‐TrFE) NF mat is exploited as a piezoelectric layer of the piezocomposite while the SWCNT film is applied as a transparent conductive electrode thereof. The use of these 1D nanomaterials allows the piezocomposite not only to be high transparency along with low diffusion of light (i.e., haze factor) but also to exhibit enhanced mechanical properties. In addition, the coupling effect of piezo‐ and flexoelectricity exhibited from the electrospun NFs and the acid‐doping effect conducted on the SWCNTs facilitates a significant improvement in kinetic energy‐harvesting performance, leading to a maximum output voltage of 26.8 V. Moreover, electrospinning and aerosol chemical vapor deposition methods employed here are facile, scalable, and cost‐effective, thus are expected to accelerate the development of industrially feasible next‐generation wearable electronics. [ABSTRACT FROM AUTHOR]

Hierarchical core–shell (C–S) heterostructures composed of a NiO shell deposited onto stacked‐cup carbon nanotubes (SCCNTs) are synthesized by atomic layer deposition (ALD). A film of NiO particles (0.80–21.8 nm in thickness) is uniformly deposited onto the inner and outer walls of the SCCNTs. The electrical resistance of the samples is found to increase of many orders of magnitude with the increasing of the NiO thickness. The response of NiO–SCCNT sensors toward low concentrations of acetone and ethanol at 200 °C is studied. The sensing mechanism is based on the modulation of the hole‐accumulation region in the NiO shell layer upon chemisorption of the reducing gas molecules. The electrical conduction mechanism is further studied by the incorporation of an Al2O3 dielectric layer at NiO and SCCNT interfaces. The investigations on NiO–Al2O3–SCCNT, Al2O3–SCCNT, and NiO–SCCNT coaxial heterostructures reveal that the sensing mechanism is strictly related to the NiO shell layer. The remarkable performance of the NiO–SCCNT sensors toward acetone and ethanol benefits from the conformal coating by ALD, large surface area of the SCCNTs, and the optimized p‐NiO shell layer thickness followed by the radial modulation of the space‐charge region. [ABSTRACT FROM AUTHOR]

The liver plays an important role in metabolizing foreign materials, such as drugs. The high accumulation of carbon nanotubes and other hydrophobic nanoparticles in the liver has raised concerns that nanoparticles may interfere with liver metabolic function. We report here that carbon nanotubes enter hepatic cells after intravenous introduction and interact with CYP enzymes, including CYP3A4. Surface chemical modifications alter the carbon nanotubes' interactions with CYP450 enzymes in human liver microsomes. They enhance, inhibit, or have no effect on the enzymatic function of CYP3A4. Using a cheminformatics analysis, certain chemical structures are identified on the surface of the carbon nanotubes that induce an enzyme inhibitory effect or prevent disruption of CYP3A4 enzymes. [ABSTRACT FROM AUTHOR]

Core-shell-structured, ultrafine SnO x/carbon nanofiber (CNF)/carbon nanotube composite films are in situ synthesized by electrospinning through a dual nozzle. The carbon shell layer functions as a buffer to prevent the separation of SnO x particles from the CNF core, allowing full utilization of high-capacity SnO x in both Li-ion and Na-ion batteries. The composite electrodes reveal an anomalous Li- and Na-ion storage mechanism where all the intermediate phases, like Li xSn and Na xSn alloys, maintain amorphous states during the entire charge/discharge process. The uniform dispersion on an atomic scale and the amorphous state of the SnO x particles remain intact in the carbon matrix without growth or crystallization even after 300 cycles, which is responsible for sustaining excellent capacity retention of the electrodes. These discoveries not only shed new insights into fundamental understanding of the electrochemical behavior of SnO x electrodes but also offer a potential strategy to improve the cyclic stability of other types of alloy anodes that suffer from rapid capacity decays due to large volume changes. [ABSTRACT FROM AUTHOR]

Carbon nanofibrous (CNF) films are of great interest for various applications, e.g., as substrates for electrodes, sensors, or catalysts. Here, a fast microwave-assisted synthesis is reported to fabricate square-centimeter large free-standing carbon nanofibrous films of approximately 10 μm thickness utilizing nickel-based catalysts and ethanol as carbon source. The obtained CNF coatings exhibit a good stability and partial self-delamination from the substrate is observed, which enables their easy detachment from the substrate without the need for further treatment. Scanning electron microscopy is applied to investigate the morphology of the films and to develop a growth model. [ABSTRACT FROM AUTHOR]

The materials commonly used to fabricate thermoelectric devices are tellurium, lead, and germanium. These materials ensure the best thermoelectric performance, but exhibit drawbacks in terms of availability, sustainability, cost, and manufacturing complexity. Moreover, they do not guarantee a safe and cheap implementation in wearable thermoelectric applications. Here, p‐Type and n‐type flexible thermoelectric textiles are produced with sustainable and low‐cost materials through green and scalable processes. Cotton is functionalized with inks made with biopolyester and carbon nanomaterials. Depending on the nanofiller, i.e., graphene nanoplatelets, carbon nanotubes, or carbon nanofibers, positive or negative Seebeck coefficient values are obtained, resulting in a remarkable electrical conductivity value of 55 S cm−1 using carbon nanotubes. The best bending and washing stability are registered for the carbon nanofiber‐based biocomposites, which increase their electrical resistance by 5 times after repeated bending cycles and only by 30% after washing. Finally, in‐plane flexible thermoelectric generators coupling the best p‐ and n‐type materials are fabricated and analysed, resulting in an output voltage of ≈1.65 mV and a maximum output power of ≈1.0 nW by connecting only 2 p/n thermocouples at a temperature difference of 70 °C. [ABSTRACT FROM AUTHOR]

The principle of a "catalytic nanosponge" that combines the catalysis of organosulfur oxidation and sequestration of the products from reaction mixtures is demonstrated. Group VI metal oxide nanoparticles (CrOx, MoOx, WOx) are embedded within hollow graphitized carbon nanofibers (GNFs), which act as nanoscale reaction vessels for oxidation reactions used in the decontamination of fuel. When immersed in a model liquid alkane fuel contaminated with organosulfur compounds (benzothiophene, dibenzothiophene, dimethyldibenzothiophene), it is found that MoO2@GNF nanoreactors, comprising 30 nm molybdenum dioxide nanoparticles grown within the channel of GNFs, show superior abilities toward oxidative desulfurization (ODS), affording over 98% sulfur removal at only 5.9 mol% catalyst loading. The role of the carbon nanoreactor in MoO2@GNF is to enhance the activity and stability of catalytic centers over at least 5 cycles. Surprisingly, the nanotube cavity can selectively absorb and remove the ODS products (sulfoxides and sulfones) from several model fuel systems. This effect is related to an adsorptive desulfurization (ADS) mechanism, which in combination with ODS within the same material, yields a "catalytic nanosponge" MoO2@GNF. This innovative ODS and ADS synergistic functionality negates the need for a solvent extraction step in fuel desulfurization and produces ultralow sulfur fuel. [ABSTRACT FROM AUTHOR]

The exploration of cost‐effective yet high‐efficiency inexpensive electrocatalysts for the hydrogen evolution reaction (HER) is of critical significance for future renewable energy conversion technologies. A feasible electrospinning strategy to construct a novel 1D hierarchical nanoarchitecture comprising Ni3Fe nanoalloy‐encapsulated carbon nanotubes grown onto N‐doped carbon nanofibers (abbreviated as Ni3Fe@N‐C NT/NFs) is demonstrated here. Benefiting from the abundant firmly immobilized Ni3Fe nanoparticles for catalytic sites and hierarchical fibrous nanostructures for effective electron transport and mass diffusion, the resultant Ni3Fe@N‐C NT/NFs display an extraordinary HER activity with a low overpotential of 72 mV to reach a current density of 10 mA cm−2 in KOH medium and a remarkable stability for 40 000 s. Theoretical studies corroborate that the resultant Ni3Fe@N‐C NT/NFs exhibit a favorable Gibbs free energy of hydrogen adsorption (ΔGH* = −0.14 eV), further manifesting their superior HER activity. The present work will advance the development of highly efficient nonprecious electrocatalysts for energy conversion. A superior hydrogen evolution reaction electrocatalyst consisting of novel 1D hierarchical nanoarchitecture comprising Ni3Fe nanoalloy‐encapsulated carbon nanotubes grown onto N‐doped carbon nanofibers is developed via a feasible electrospinning strategy. Both experimental and theoretical studies illustrate that the extraordinary activity of the Ni3Fe@N‐C NT/NFs attributed to abundant firmly immobilized Ni3Fe nanoparticles, hierarchical fibrous nanostructure, and favorable Gibbs free energy of hydrogen adsorption (ΔGH* = −0.14 eV). [ABSTRACT FROM AUTHOR]

Due to their high electrical and thermal conductivity and structural stability, carbon nanotubes (CNTs) can carry very high electrical currents before failure. On page 3241, J. Kono and team report a fiber consisting of tightly packed and well aligned CNTs. This fiber displays the highest current‐carrying capacity (CCC) ever reported for a CNT power cable. When normalized by mass, the CCC value of the CNT cable largely surpasses copper wire, making the CNT cable promising for lightweight power transmission, such as in aerospace systems. [ABSTRACT FROM AUTHOR]