Graphene, the thinnest, strongest, and stiffest material with exceptional thermal conductivity and electron mobility, has increasingly received world‐wide attention in the past few years. These unique properties may lead to novel or improved technologies to address the pressing global challenges in many applications including transparent conducting electrodes, field effect transistors, flexible touch screen, single‐molecule gas detection, desalination, DNA sequencing, osmotic energy production, etc. To realize these applications, it is necessary to transfer graphene films from growth substrate to target substrate with large‐area, clean, and low defect surface, which are crucial to the performances of large‐area graphene devices. This critical review assesses the recent development in transferring large‐area graphene grown on Fe, Ru, Co, Ir, Ni, Pt, Au, Cu, and some nonmetal substrates by using various synthesized methods. Among them, the transfers of the most attention kinds of graphene synthesized on Cu and SiC substrates are discussed emphatically. The advances and the main challenges of each wet and dry transfer method for obtaining the transferred graphene film with large‐area, clean, and low defect surface are also reviewed. Finally, the article concludes the most promising methods and the further prospects of graphene transfer.

As an emerging technology, forward osmosis (FO) has shown great promise in energy production from the mixing of fresh water and seawater in estuaries. However, the power density levels of the present commercial FO membranes hinder their practical applications in power generation due to the requirement for extremely large areas of membrane. Here, we use functionalized porous-single-layer graphene as a FO membrane and study the transport performances of the membrane using molecular dynamics simulation. For the FO system using fluorinated porous graphene (pore-diameter 11.7 Å, porosity 10%), with an excellent performance for salt rejection, the water flux is 28.1 L cm À2 h which is about 1.8 Â 10 4 times higher than that of a typical cellulose triacetate membrane. Such high water flux will certainly bring about a very high power density in pressure retarded osmosis power generation. This work may generate potential opportunities for functionalized graphene in FO power generation, seawater desalination and so forth.

Wearing surgical masks is one of the best protective measures to protect humans from viral invasion during the 2019 coronavirus (COVID-19) outbreak. However, wearing surgical masks for extended periods will cause uncomfortable sweltering sense to users and are easy to breed bacteria. Here, we reported a novel fibrous membrane with outstanding comfortability and antibacterial activity prepared by PP ultrafine fiber nonwovens and antibacterial functionalized h-BN nanoparticles (QAC/h-BN). The thermal conductivity of commercial PP nonwovens was only 0.13 W m–1 K–1, but that of the QAC/h-BN/PP nanocomposite fibrous membranes can reach 0.88 W m–1 K–1, an enhancement of 706.5% than commercial PP nonwovens. The surface temperature of commercial PP surgical masks was 31.8 °C when the wearing time was 60 min. In contrast, QAC/h-BN/PP surgical masks can reach 33.6 °C at the same tested time, exhibiting stronger heat dissipation than commercial PP surgical masks. Besides, the antibacterial rates of QAC/h-BN/PP nanocomposite fibrous membranes were 99.3% for E. coli and 96.1% for S. aureus, and their antibacterial mechanism was based on “contact killing” without the release of unfavorable biocides. We think that the QAC/h-BN/PP nanocomposite fibrous membranes could provide better protection to people.

Guanidinium-functionalized NF membranes which have integrated high permselectivity and superior fouling resistance properties are promising materials for fabricating a new generation of anti-fouling/antimicrobial surfaces.

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Detailed characterization of the crystallization behavior is important for obtaining better structure property correlations of the isotactic polypropylene (iPP), however, attributed to the complexity in ZN-iPP polymerization, the relationship between crystallization behavior and the stereo-defect distribution of iPP is still under debate. In this study, the crystallization kinetics of the primary nucleation, crystal growth and overall crystallization of two iPP samples (PP-A and PP-B) with nearly same average isotacticity but different stereo-defect distribution (the stereo-defect distribution of PP-B is more uniform than PP-A) were investigated. The results of isothermal crystallization kinetics showed that the overall crystallization rate of PP-A was much higher than that of PP-B; but the analysis of self-nucleation isothermal crystallization kinetics and the polarized optical microscopy (POM) observation indicated that the high overall crystallization rate of PP-A was attributed to the high primary nucleation rate of the resin. The stereodefect distribution plays an important role in determining both the nucleation kinetics and crystal grow kinetics, and thus influence the overall crystallization kinetics. A more uniform distribution of stereo-defects restrains the crystallization rate of iPP, moreover, it has more influence on nucleation kinetics, comparing with the crystal growth.

Stimulus-responsive materials with designable integrated functions bridge the intelligent systems in future lifestyles with the Internet of Things (IoT). The growing trend for IoT and corresponding advanced devices will involve a great number of electronic disposables, which may place heavy burdens on the environment. Here, an elaborately designed multistage responsive material is reported for real-time, reversible light-writing based on organized stage-by-stage responsive behaviors and polarity-dependent physicochemical fluorescence response, where the stimulus is accurately delivered through a completely reversible "light-heat-fluorescence" pathway. The resulted materials can be pollution-freely written by hand-controlled near-infrared laser within 5 s, spontaneously erased within 20 s, and exhibit excellent re-writing ability (more than 5000 times while the variance of chromaticity coordinates <0.0008), which is difficult to achieve by traditional laser writing technologies. This study is a step toward high-performance long-life functional devices based on reversible multistage responsive materials for future IoT lifestyles.

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