Gang Wang

Mixed‐conducting ceramic hollow fiber membranes are a versatile platform for oxygen separation, value‐added chemical production, and oxy‐combustion. Because oxygen permeation is thermally activated, these systems typically rely on bulky, energy‐intensive furnaces that suffer from low efficiency and large thermal inertia. Joule (resistive) heating, achieved by directly applying voltage or current to the fibers, offers a compact and efficient alternative. Yet, this self‐heating strategy has not been explored in methane‐fueled membrane reactors. Here, La _0.6 Sr _0.4 Co _0.2 Fe _0.8 O _3‐δ (LSCF) hollow fiber membranes are fabricated via a template‐assisted rotating method and used as a model system. Their oxygen permeation under Joule heating is evaluated, followed by stability testing over ~75 h and 20 thermal cycles. A methane‐fueled membrane reactor is then examined, focusing on the influence of applied voltage (temperature) and methane concentration on conversion and selectivity. Long‐term reactor stability (~75 h) and the mechanisms governing oxygen transport and performance are also analyzed.

Ultrathin, lightweight, and flexible aligned single-walled carbon nanotube (SWCNT) films are fabricated by a facile, environmentally friendly, and scalable printing methodology. The aligned pattern and outstanding intrinsic properties render “metal-like” thermal conductivity of the SWCNT films, as well as excellent mechanical strength, flexibility, and hydrophobicity. Further, the aligned cellular microstructure promotes the electromagnetic interference (EMI) shielding ability of the SWCNTs, leading to excellent shielding effectiveness (SE) of ~ 39 to 90 dB despite a density of only ~ 0.6 g cm⁻³ at thicknesses of merely 1.5–24 µm, respectively. An ultrahigh thickness-specific SE of 25 693 dB mm⁻¹ and an unprecedented normalized specific SE of 428 222 dB cm² g⁻¹ are accomplished by the freestanding SWCNT films, significantly surpassing previously reported shielding materials. In addition to an EMI SE greater than 54 dB in an ultra-broadband frequency range of around 400 GHz, the films demonstrate excellent EMI shielding stability and reliability when subjected to mechanical deformation, chemical (acid/alkali/organic solvent) corrosion, and high-/low-temperature environments. The novel printed SWCNT films offer significant potential for practical applications in the aerospace, defense, precision components, and smart wearable electronics industries.

Microscale fiber-based supercapacitors have become increasingly important for the needs of flexible, wearable, and lightweight portable electronics. Fiber electrodes without pre-existing cores enable a wider selection of materials and geometries than is possible through core-containing electrodes. The carbonization of fibrous precursors using an electrically driven route, different from a conventional high-temperature process, is particularly promising for achieving this structure. Here, we present a facile and low-cost process for producing high-performance microfiber supercapacitor electrodes based on carbonaceous materials without cores. Fibrous carbon nanotubes-agarose composite hydrogels, formed by an extrusion process, are converted to a composite fiber consisting of carbon nanotubes (CNTs) surrounded by an amorphous carbon (aC) matrix via Joule heating. When assembled into symmetrical two-electrode cells, the composite fiber (aC-CNTs) supercapacitor electrodes deliver a volumetric capacitance of 5.1 F cm⁻³ even at a high current density of 118 mA cm⁻³. Based on electrochemical impedance spectroscopy analysis, it is revealed that high electrochemical properties are attributed to fast response kinetics with a characteristic time constant of 2.5 s. The aC-CNTs fiber electrodes exhibit a 94% capacitance retention at 14 mA cm⁻³ for at least 10,000 charge-discharge cycles even when deformed (90° bend), which is essentially the same as that (96%) when not deformed. The aC-CNTs fiber electrodes also demonstrate excellent storage performance under mechanical deformation—for example, 1000 bending-straightening cycles.

The electrical conductivity and mechanical strength of fibers constructed from single walled carbon nanotubes (CNTs) are usually limited by the weak interactions between individual CNTs. In this work, we report a significant enhancement of both of these properties through chemical cross-linking of individual CNTs. The CNT fibers are made by wet-spinning a CNT solution that contains 1,3,5-tris(2′-bromophenyl)benzene (2TBB) molecules as the cross-linking agent and the cross-linking is subsequently driven by Joule heating. Cross-linking with 2TBB increases the conductivity of the CNT fibers by a factor of ~100 and increases the tensile strength on average by 47%; in contrast, the tensile strength of CNT fibers fabricated without 2TBB decreases after the same Joule heating process. Symmetrical supercapacitors made from the 2TBB-treated CNT fibers exhibit a remarkably high volumetric energy density of ~4.5 mWh cm-3 and a power density of ~1.3 W cm-3.

A SWNTs cylindrical fiber is fabricated with diamond wire drawing dies and the SWNT ribbon-like fiber is obtained by pressure treatment. The tensile strength and Young's modulus of ribbon-like fibers can be enhanced with a maximum factor about 55.

When graphene almost completely complies with the morphology of a SiO ₂ micron-scale hole array (MSHA) substrate, the effect of graphene's surface morphology to the wettability of graphene will be greatly facilitated by the regulation effect of MSHA.

Due to the lattice epitaxy between MoS₂ and gold, ultrathin equilateral gold nanotriangles and bowties can be grown on layered MoS₂ with favorable orientations, which further enhance the Raman signals of MoS₂ greatly.

A voltage is induced when the graphene nanodrums move and its magnitude and sign depend on the upheaval/sinking of the nanodrums.

In this work, a simple, productive and low cost method is reported for synthesizing few-layer graphenes directly on SiO₂/Si substrates.