RESUMEN
Functional phase-change fabrics hold great promise as wearable clothing. However, how to enable a phase-change fabric with the combined features of excellent structural flexibility and robustness, integrated multifunctionality, superior stability, and durability, as well as facile and scalable manufacturing, still remains a significant challenge. Herein, we demonstrated a scalable and controllable three-dimensional (3D) printing strategy for manufacturing flexible, thin, and robust phase-change nonwoven fabric (PCNF), with abundant and regular breathable pores as well as uniform and tight embedment of highly interconnected single-walled carbon nanotubes (SWNTs) into hydrophobic filaments built by intertwining solid-solid phase-change polymer chains together. The remarkable architectural features enabled an integral whole of the fabric, ready air exchange, superior water impermeability, highly efficient heat harvesting and storage, and effective absorption and reflection of electromagnetic waves, thereby delivering an exceptional combined function of breathability, waterproofness, thermal regulation, and radiation resistance, and meanwhile featuring superior thermal stability and outstanding resistance to stretching/folding fatigue even at cycles up to 2000. This work sheds light on effective strategies for manufacturing wearable phase-change fabrics with multifunctionality and high stability in a scalable manner toward future uses.
RESUMEN
Carbon nanotube (CNT) films have demonstrated great potential for highly efficient thermal management materials. However, how to enable a combined feature of excellent thermal conductivity and structural robustness, which is crucial for the high-performance realization, still remains challenging. Herein, an effective and facile strategy to solve the problem was proposed by developing a graphene (G)/CNT film with highly aligned welding of ultrathin G layer to robust CNT film. The unique architectural features of the obtained composite film enabled a high tensile strength (116 MPa) and electric conductivity (1.7 × 103S cm-1). Importantly, the thermal conductivity was significantly improved compared to neat CNT film, and reached as high as 174 W m-1K-1. In addition, the G/CNT film featured a superior electromagnetic shielding performance. This work provides useful guidelines for designing and fabricating the composite CNT film with prominent thermal conductivity, as well as excellent mechanical and electrical properties.
RESUMEN
Continuous-flow photoreactors hold great promise for the highly efficient photodegradation of pollutants due to their continuity and sustainability. However, how to enable a continuous-flow photoreactor with the combined features of high photodegradation efficiency and durability as well as broad-wavelength light absorption and large-scale processing remains a significant challenge. Herein, we demonstrate a facile and effective strategy to construct a sieve-like carbon nanotube (CNT)/TiO2 nanowire film (SCTF) with superior flexibility (180° bending), high tensile strength (75-82 MPa), good surface wettability, essential light penetration and convenient visible light absorption. Significantly, the unique architecture, featuring abundant, well-ordered and uniform mesopores with ca. 70 µm in diameter, as well as a homogenous distribution of TiO2 nanowires with an average diameter of ca. 500 nm, could act as a "waterway" for efficient solution infiltration through the SCTF, thereby, enabling the photocatalytic degradation of polluted water in a continuous-flow mode. The optimized SCTF-2.5 displayed favorable photocatalytic behavior with 96% degradation of rhodamine B (RhB) within 80 min and a rate constant of 0.0394 min-1. The continuous-flow photodegradation device made using SCTF-2.5 featured exceptional photocatalytic behavior for the continuous degradation of RhB under simulated solar irradiation with a high degradation ratio (99.6%) and long-term stability (99.2% retention after working continuously for 72 h). This work sheds light on new strategies for designing and fabricating high-performance continuous-flow photoreactors toward future uses.
RESUMEN
Effective and reliable encapsulation of phase change materials (PCMs) is essential and critical to the high-performance solar-thermal energy harvesting and storage. However, challenges remain pertaining to manufacturing scalability, high efficiency in energy storage/release, and anti-leakage of melted PCMs. Herein, inspired by natural legume, a facile and scalable extrusion-based core-sheath 3D printing strategy is demonstrated for directly constructing bean-pod-structured octadecane (OD)/graphene (BOG) phase change microlattices, with regular porous configuration as well as individual and effective encapsulation of OD "beans" into highly interconnected graphene network wrapping layer built by closely stacked and aligned graphene sheets. The unique architectural features enable the ready spreading of light into the interior of phase change microlattice, a high transversal thermal conductivity of 1.67 W m-1 K-1 , and rapid solar-thermal energy harvesting and transfer, thereby delivering a high solar-thermal energy storage efficiency, and a large phase change enthalpy of 190 J g-1 with 99.1% retention after 200 cycles. Most importantly, such encapsulated PCMs feature an exceptional thermal reliability and stability, with no leakage and shape variation even at 1000 thermal cycles and partial damage of BOG. This work validates the feasibility of scalably printing practical encapsulated PCMs, which may revolutionize the fabrication of composite PCMs for solar-thermal energy storage devices.
