Solar steam generation is achieved by localized heating system using various floating photothermal materials. However, the steam generation efficiency is hindered by the difficulty in obtaining a ...photothermal material with ultrathin structure yet sufficient solar spectrum absorption capability. Herein, for the first time, an ultrathin 2D porous photothermal film based on MoS2 nanosheets and single‐walled nanotube (SWNT) films is prepared. The as‐prepared SWNT–MoS2 film exhibits an absorption of more than 82% over the whole solar spectrum range even with an ultrathin thickness of ≈120 nm. Moreover, the SWNT–MoS2 film floating on the water surface can generate a sharp temperature gradient due to the localized heat confinement effect. Meanwhile, the ultrathin and porous structure effectively facilitates the fast water vapor escaping, consequently an impressively high evaporation efficiency of 91.5% is achieved. Additionally, the superior mechanical strength of the SWNT–MoS2 film enables the film to be reused for atleast 20 solar illumination cycles and maintains stable water productivity as well as high salt rejection performance. This rational designed hybrid architecture provides a novel strategy for constructing 2D‐based nanomaterials for solar energy harvesting, chemical separation, and related technologies.
To address the difficulties in obtaining photothermal materials with ultrathin structure yet sufficient solar spectrum absorption capability, an ultrathin and self‐floating SWNT–MoS2 hybrid film is designed. As an interfacial heating membrane, this SWNT–MoS2 film shows enhanced steam generation efficiency and superior recycle stability due to the ultrathin and porous structure as well as high mechanical strength.
Carbon nanotube functional materials (CNTFMs) represent an important research field in transforming nanoscience and nanotechnology into practical applications, with potential impact in a wide realm ...of science, technology, and engineering. In this review, we combine the state-of-the-art research activities of CNTFMs with the application prospect, to highlight critical issues and identify future challenges. We focus on macroscopic long fibers, thin films, and bulk sponges which are typical CNTFMs in different dimensions with distinct characteristics, and also cover a variety of derived composite/hierarchical materials. Critical issues related to their structures, properties, and applications as robust conductive skeletons or high-performance flexible electrodes in mechanical and electronic devices, advanced energy conversion and storage systems, and environmental areas have been discussed specifically. Finally, possible solutions and directions are proposed for overcoming current obstacles and promoting future efforts in the field.
Metal-organic frameworks (MOFs) with high porosity and designable functionality make it possible to access the merits of high permeability and selectivity. However, scalable fabrication methods to ...produce mixed matrix membranes (MMMs) with good flexibility and ultrahigh MOF loading are urgently needed yet largely unmet. Herein, we report a thermally induced phase separation-hot pressing (TIPS-HoP) strategy to roll-to-roll produce 10 distinct MOF-membranes (loadings up to 86 wt%). Ultrahigh-molecular-weight polyethylene interweaving the MOF particles contributes to their mechanical strength. Rejections (99%) of organic dyes with a water flux of 125.7 L m
h
bar
under cross-flow filtration mode. The micron-sized channels between the MOF particles translate into fast water permeation, while the porous MOFs reject solutes through rapid adsorption. This strategy paves ways for developing high-performance membrane adsorbers for crucial separation processes. As a proof-of-concept, the abilities of the membrane adsorbers for separating racemates and proteins have been demonstrated.
Designing high‐performance and low‐cost electrocatalysts is crucial for the electrochemical production of hydrogen. Dislocation‐strained IrNi nanoparticles loaded on a carbon nanotube sponge ...(DSIrNi@CNTS) driven by unsteady thermal shock in an extreme environment are reported here as a highly efficient hydrogen evolution reaction (HER) catalyst. Experimental results demonstrate that numerous dislocations are kinetically trapped in self‐assembled IrNi nanoparticles due to the ultrafast quenching and different atomic radii, which can induce strain effects into the IrNi nanoparticles. Such strain‐induced high‐energy surface structures arising from bulk defects (dislocations), are more likely to be resistant to surface restructuring during catalysis. The catalyst exhibits outstanding HER activity with only 17 mV overpotential to achieve 10 mA cm−2 in an alkaline electrolyte with fabulous stability, exceeding state‐of‐the‐art Pt/C catalysts. These density functional theory results demonstrate that the electronic structure of as‐synthesized IrNi nanostructure can be optimized by the strain effects induced by the dislocations, and the free energy of HER can be tuned toward the optimal region.
Dislocation‐strained IrNi nanoparticles with competitive HER activity are realized by unsteady thermal shock progress in an extreme environment, and they are uniformly distributed within a carbon nanotube sponge (DSIrNi@CNTS). Numerous dislocations are generated in self‐assembled IrNi nanoparticles due to ultrafast quenching, inducing strain effects into the IrNi nanoparticles, which optimize the electronic structure of the active sites.
Deformation‐tolerant devices are vital for the development of high‐tech electronics of unconventional forms. In this study, a highly compressible supercapacitor has been fabricated by using newly ...developed polypyrrole‐mediated graphene foam as electrode. The assembled supercapacitor performs based on the unique and robust foam electrodes achieves superb compression tolerance without significant variation of capacitances under long‐term compressive loading and unloading processes.
Transparent, stretchable films of carbon nanotubes (CNTs) have attracted significant attention for applications in flexible electronics, while the lack of structural strength in CNT networks leads to ...deformation and failure under high mechanical load. In this work, enhancement of the strength and load transfer capabilities of CNT networks by chemical vapor deposition of graphene in the nanotube voids is proposed. The graphene hybridization significantly strengthens the CNT networks, especially at nanotube joints, and enhances their resistance to buckling and bundling under large cyclic strain up to 20%. The hybridized films show linear and reproducible responses to tensile strains, which have been applied in strain sensors to detect human motions with fast response, high sensitivity, and durability.
In‐situ graphene hybridization is applied to enhance the structural strength in carbon nanotube (CNT) networks under high mechanical load. The CNT–graphene hybrids effectively resist the buckling deformation of CNT network due to strong interaction and effective load transfer within the hybridized films, and could be applied in wearable and implantable electronics.
With its synergistic toughening effect and hierarchical micro/nanoscale structure, natural nacre sets a “gold standard” for nacre-inspired materials with integrated high strength and toughness. We ...demonstrated strong and tough ternary bioinspired nanocomposites through synergistic toughening of reduced graphene oxide and double-walled carbon nanotube (DWNT) and covalent bonding. The tensile strength and toughness of this kind of ternary bioinspired nanocomposites reaches 374.1 ± 22.8 MPa and 9.2 ± 0.8 MJ/m3, which is 2.6 and 3.3 times that of pure reduced graphene oxide film, respectively. Furthermore, this ternary bioinspired nanocomposite has a high conductivity of 394.0 ± 6.8 S/cm and also shows excellent fatigue-resistant properties, which may enable this material to be used in aerospace, flexible energy devices, and artificial muscle. The synergistic building blocks with covalent bonding for constructing ternary bioinspired nanocomposites can serve as the basis of a strategy for the construction of integrated, high-performance, reduced graphene oxide (rGO)-based nanocomposites in the future.
Highly conductive semitransparent graphene sheets are combined with an n‐type silicon (n‐Si) wafer to fabricate solar cells with power conversion efficiencies up to 1.5% at AM 1.5 and an illumination ...intensity of 100 mW cm−2. The Schottky junction solar cells can be extended to other semiconducting materials in which graphene serves multiple functions as active junction layer, charge transport path, and transparent electrode.
Organic phase change materials are usually insulating in nature, and they are unlikely to directly trigger latent heat storage through an electrical way. Here we report a multifunctional phase change ...composite in which the energy storage can be driven by small voltages (e.g., 1.5 V) or light illumination with high electro-to-heat or photo-to-thermal storage efficiencies (40% to 60%). The composite is composed of paraffin wax infiltrated into a porous, deformable carbon nanotube sponge; the latter not only acts as a flexible encapsulation scaffold for wax but also maintains a highly conductive network during the phase change process (for both solid and liquid states). Uniform interpenetration between the nanotube network and paraffin wax with high affinity results in enhanced phase change enthalpy and thermal conductivity compared to pure paraffin wax. Our phase change composite can store energy in practical ways such as by sunlight absorption or under voltages applied by conventional lithium-ion batteries.
Many of the applications proposed for nanowires and carbon nanotubes require these components to be organized over large areas with controlled orientation and density. Although progress has been made ...with directed assembly and Langmuir-Blodgett approaches, it is unclear whether these techniques can be scaled to large wafers and non-rigid substrates. Here, we describe a general and scalable approach for large-area, uniformly aligned and controlled-density nanowire and nanotube films, which involves expanding a bubble from a homogeneous suspension of these materials. The blown-bubble films were transferred to single-crystal wafers of at least 200 mm in diameter, flexible plastics sheets of dimensions of at least 225 x 300 mm(2) and highly curved surfaces, and were also suspended across open frames. In addition, electrical measurements show that large arrays of nanowire field-effect transistors can be efficiently fabricated on the wafer scale. Given the potential of blown film extrusion to produce continuous films with widths exceeding 1 m, we believe that our approach could allow the unique properties of nanowires and nanotubes to be exploited in applications requiring large areas and relatively modest device densities.
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