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Graphene growth on widely used dielectrics/insulators via chemical vapor deposition (CVD) is a strategy toward transfer-free applications of CVD graphene for the realization of advanced composite materials. Here, we develop graphene-skinned alumina fibers/fabrics (GAFs/GAFFs) through graphene CVD growth on commercial alumina fibers/fabrics (AFs/AFFs). We reveal a vapor-surface-solid growth model on a non-metallic substrate, which is distinct from the well-established vapor-solid model on conventional non-catalytic non-metallic substrates, but bears a closer resemblance to that observed on catalytic metallic substrates. The metalloid-catalytic growth of graphene on AFs/AFFs resulted in reduced growth temperature (~200 °C lower) and accelerated growth rate (~3.4 times faster) compared to that obtained on a representative non-metallic counterpart, quartz fiber. The fabricated GAFF features a wide-range tunable electrical conductivity (1-15000 Ω sq−1), high tensile strength (>1.5 GPa), lightweight, flexibility, and a hierarchical macrostructure. These attributes are inherited from both graphene and AFF, making GAFF promising for various applications including electrical heating and electromagnetic interference shielding. Beyond laboratory level preparation, the stable mass production of large-scale GAFF has been achieved through a home-made roll-to-roll system with capacity of 468-93600 m2/year depending on product specifications, providing foundations for the subsequent industrialization of this material, enabling its widespread adoption in various industries. Chemical vapor deposition (CVD) of graphene on widely used insulators can promote its application for functional composite materials. Here, the authors report the large-scale production of graphene alumina fibers/fabrics via a metalloid-catalytic CVD growth process on commercial alumina, showing their application for electrical heating and electromagnetic shielding. [ABSTRACT FROM AUTHOR] more...

Direct chemical vapor deposition (CVD) growth of graphene on dielectric/insulating materials is a promising strategy for subsequent transfer-free applications of graphene. However, graphene growth on noncatalytic substrates is faced with thorny issues, especially the limited growth rate, which severely hinders mass production and practical applications. Herein, graphene glass fiber fabric (GGFF) is developed by graphene CVD growth on glass fiber fabric. Dichloromethane is applied as a carbon precursor to accelerate graphene growth, which has a low decomposition energy barrier, and more importantly, the produced high-electronegativity Cl radical can enhance adsorption of active carbon species by Cl–CH2 coadsorption and facilitate H detachment from graphene edges. Consequently, the growth rate is increased by ~3 orders of magnitude and carbon utilization by ~960-fold, compared with conventional methane precursor. The advantageous hierarchical conductive configuration of lightweight, flexible GGFF makes it an ultrasensitive pressure sensor for human motion and physiological monitoring, such as pulse and vocal signals. To solve the difficult problems with CVD of graphene on non-metallic substrates, researchers used dichloromethane as a C precursor with a multispecies coadsorption mechanism for more efficient graphene coating on fiber fabrics. [ABSTRACT FROM AUTHOR] more...

The lightweight, flexible, high‐performance electrothermal material is in high demand in object thermal management. Graphene glass fiber fabric (GGFF) is characterized by excellent electrical conductivity, light weight, and high flexibility, showing superiorities as an electrothermal material. However, the traditional single‐carbon‐precursor chemical vapor deposition (CVD) graphene growth strategy commonly suffers from the severe thickness nonuniformity of the large‐sized graphene film along the gas‐flowing direction. Herein, a complementary CVD graphene growth strategy based on the simultaneous introduction of high‐ and low‐decomposition‐energy‐barrier mixed carbon precursors is developed. In this way, the large‐area uniform GGFF with a dramatically decreased nonuniformity coefficient is fabricated (0.260 in 40 cm × 4 cm). GGFF‐based heater presents a widely tunable temperature range (20–170 °C) at low working voltage (<10 V) and uniform large‐area heating temperature (171.4 ± 3.6 °C in 20 cm × 15 cm), which realizes remarkable anti/deicing performances under the low energy consumption (fast ice melting rate of 79 s mm−1 under a low energy consumption of 0.066 kWh mm−1 m−2). The large‐area uniform GGFF possesses substantial advantages for applications in thermal management, and the complementary CVD fabrication strategy shows reliable scalability and universality, which can be extended to the synthesis of various materials. [ABSTRACT FROM AUTHOR] more...

Direct synthesis of graphene on nonmetallic substrates via chemical vapor deposition (CVD) has become a frontier research realm targeting transfer-free applications of CVD graphene. However, the stable mass production of graphene with a favorable growth rate and quality remains a grand challenge. Herein, graphene glass fiber fabric (GGFF) was successfully developed through the controllable growth of graphene on non-catalytic glass fiber fabric, employing a synergistic binary-precursor CVD strategy to alleviate the dilemma between growth rate and quality. The binary precursors consisted of acetylene and acetone, where acetylene with high decomposition efficiency fed rapid graphene growth while oxygen-containing acetone was adopted for improving the layer uniformity and quality. Notably, the bifurcating introducing-confluent premixing (BI-CP) system was self-built for the controllable introduction of gas and liquid precursors, enabling the stable production of GGFF. GGFF features solar absorption and infrared emission properties, based on which the self-adaptive dual-mode thermal management film was developed. This film can automatically switch between heating and cooling modes by spontaneously perceiving the temperature, achieving excellent thermal management performances with heating and cooling power of ∼501.2 and ∼108.6 W m−2, respectively. These findings unlock a new strategy for the large-scale batch production of graphene materials and inspire advanced possibilities for further applications. [ABSTRACT FROM AUTHOR] more...

Graphene‐skinned fiber fabric is prepared by chemical vapor deposition (CVD) of continuous graphene on fabric, which enables conformal graphene coverage on fibers and inherits high electrical and thermal conductivity of graphene. However, in the fabric‐shaped configuration, high electrical and thermal contact resistances between fibers, and the lack of conductive and thermal pathways along radial direction of fibers limit the improvement of electrical and thermal conductivity. Herein, carbon nanotubes (CNTs), due to the 1D structure with excellent electrical and thermal conductivity, are introduced to build rich “bridges” to connect the isolated fibers to build new electron and phonon transport channels. Thus, the conceptual design of CNT/graphene‐skinned glass fiber fabric (CNT/GGFF) is creatively proposed and realized by a carefully designed CVD. Constructing the 3D electrically and thermally conductive network in CNT/GGFF leads to >90% decrease of sheet resistance, 4.5 times increase of tensile strength, and >70% decrease of thermal resistance compared with GGFF, making it promising for applications in composite materials, heat dissipation, and de‐icing. Moreover, the thermal resistance of CNT/GGFF exhibits temperature‐independent, extending applications to aviation and space because changes in thermal conductivity of traditional materials with environmental temperatures can adversely affect the thermal stability, reliability, and lifetime of aircrafts. [ABSTRACT FROM AUTHOR] more...