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Promoted by the demand for wearable devices, graphene has been proved to be a promising material for potential applications in flexible and highly sensitive strain sensors. However, low sensitivity and complex processing of graphene retard the development toward the practical applications. Here, an environment-friendly and cost-effective method to fabricate large-area ultrathin graphene films is proposed for highly sensitive flexible strain sensor. The assembled graphene films are derived rapidly at the liquid/air interface by Marangoni effect and the area can be scaled up. These graphene-based strain sensors exhibit extremely high sensitivity with gauge factor of 1037 at 2% strain, which represents the highest value for graphene platelets at this small deformation so far. This simple fabrication for strain sensors with highly sensitive performance of strain sensor makes it a novel approach to applications in electronic skin, wearable sensors, and health monitoring platforms. [ABSTRACT FROM AUTHOR]

A hybrid heterojunction and solid-state photoelectrochemical solar cell based on graphene woven fabrics (GWFs) and silicon is designed and fabricated. The GWFs are transferred onto n-Si to form a Schottky junction with an embedded polyvinyl alcohol based solid electrolyte. In the hybrid solar cell, solid electrolyte serves three purposes simutaneously; it is an anti-reflection layer, a chemical modification carrier, and a photoelectrochemical channel. The open-circuit voltage, short-circuit current density, and fill factor are all significantly improved, achieving an impressive power conversion efficiency of 11%. Solar cell models are constructed to confirm the hybrid working mechanism, with the heterojunction junction and photoelectrochemical effect functioning synergistically. [ABSTRACT FROM AUTHOR]

Sensing strain of soft materials in small scale has attracted increasing attention. In this work, graphene woven fabrics (GWFs) are explored for highly sensitive sensing. A flexible and wearable strain sensor is assembled by adhering the GWFs on polymer and medical tape composite film. The sensor exhibits the following features: ultra-light, relatively good sensitivity, high reversibility, superior physical robustness, easy fabrication, ease to follow human skin deformation, and so on. Some weak human motions are chosen to test the notable resistance change, including hand clenching, phonation, expression change, blink, breath, and pulse. Because of the distinctive features of high sensitivity and reversible extensibility, the GWFs based piezoresistive sensors have wide potential applications in fields of the displays, robotics, fatigue detection, body monitoring, and so forth. [ABSTRACT FROM AUTHOR]

The challenge in developing a protection barrier from corrosion is to develop an economical yet efficient method for the coating material. Graphene has been deemed to be an ideal coating material for anti‐corrosion, yet its long‐term performance is disappointing due to galvanic corrosion. In an effort to address issues associated with graphene materials, we have developed an amorphous nitrogen doped carbon (a‐CN) film material exhibiting remarkable anti‐corrosion properties. The anti‐corrosion performance of this material appears to be superior to graphene because of its strong ion transportation resistance. [ABSTRACT FROM AUTHOR]

New porous materials are of great importance in many technological applications. Here, the direct synthesis of multi-layer graphene and porous carbon woven composite films by chemical vapor deposition on Ni gauze templates is reported. The composite films integrate the dual advantages of graphene and porous carbon, having not only the excellent electrical properties and flexibility of graphene but also the porous characteristics of amorphous carbon. The multi-layer graphene/porous carbon woven fabric film creates a new platform for a variety of applications, such as fiber supercapacitors. The designed composite film has a capacitance of 20 μF/cm2, which is close to the theoretical value and a device areal capacitance of 44 mF/cm2. [ABSTRACT FROM AUTHOR]

A bottom‐up method to fabricate uniformly dispersed graphene quantum dots (GQDs) by atmospheric pressure CVD on copper substrates is reported. The size distribution of the GQDs can be controlled by carefully tuning the CVD growth parameters. Additionally, the GQDs can easily be transferred to other large‐scale substrates and the fabrication process is relatively simple and convenient. The GQDs deposited on transparent substrates show well‐known excitation‐dependent photoluminescence behavior. [ABSTRACT FROM AUTHOR]

An unexpected behavior of graphene in graphene–silicon heterojunction junction solar cells when it is used as the window electrode is reported. Although the synthesized mono layer graphene exhibits better transparency and conductivity, the multilayer graphene enables much higher solar conversion ability of the solar cell. This surprising observation may be because the multilayer graphene can more effectively suppress charge recombination at the heterojunction interface, which increases the fill factor and enhances the cell performance. [ABSTRACT FROM AUTHOR]

The CVD of graphene on metal substrates serves as an ideal platform for studying the nucleation and growth of two-dimensional crystals. In this paper, the size distribution and shape transformation of graphene domains at early stages of CVD are investigated. The transformation of round-shaped graphene disks into hexagonal domains during atmospheric pressure (AP)CVD on copper substrates is identified. The critical transformation size from graphene disks to hexagonal domains is ∼0.8 µm2 according to the size distribution statistics. [ABSTRACT FROM AUTHOR]

High sensitivity, transparent, flexible strain sensors based on ultrathin graphene films are demonstrated by C.‐T. Lin, Y. Fang, H. Zhu, and co‐workers on page 1322. The cost‐effective, ultrathin graphene films are fabricated at the liquid/air interface due to the Marangoni effect. This novel approach makes graphene a promising material for electronic skin, wearable sensors, and health monitoring platforms. [ABSTRACT FROM AUTHOR]

A correction to the article "Enhanced Transport of Nanoparticles Across a Porous Nanotube Sponge" that was published in a 2011 issue is presented.