This review presents insights into the fundamental challenges of wet adhesion, and the applications of catechol-functionalized hydrogels in diverse areas.

Until now, few sp2 carbon materials simultaneously exhibit superior performance for specific surface area (SSA) and electrical conductivity at bulk state. Thus, it is extremely important to make such materials at bulk scale with those two outstanding properties combined together. Here, we present a simple and green but very efficient approach using two standard and simple industry steps to make such three-dimensional graphene-based porous materials at the bulk scale, with ultrahigh SSA (3523 m2/g) and excellent bulk conductivity. We conclude that these materials consist of mainly defected/wrinkled single layer graphene sheets in the dimensional size of a few nanometers, with at least some covalent bond between each other. The outstanding properties of these materials are demonstrated by their superior supercapacitor performance in ionic liquid with specific capacitance and energy density of 231 F/g and 98 Wh/kg, respectively, so far the best reported capacitance performance for all bulk carbon materials.

It is a challenge to fabricate graphene bulk materials with properties arising from the nature of individual graphene sheets, and which assemble into monolithic three-dimensional structures. Here we report the scalable self-assembly of randomly oriented graphene sheets into additive-free, essentially homogenous graphene sponge materials that provide a combination of both cork-like and rubber-like properties. These graphene sponges, with densities similar to air, display Poisson's ratios in all directions that are near-zero and largely strain-independent during reversible compression to giant strains. And at the same time, they function as enthalpic rubbers, which can recover up to 98% compression in air and 90% in liquids, and operate between À 196 and 900°C. Furthermore, these sponges provide reversible liquid absorption for hundreds of cycles and then discharge it within seconds, while still providing an effective near-zero Poisson's ratio.

A deep UV light photodetector is assembled by coating multilayer graphene on beta-gallium oxide (β-Ga O ) wafer. Optoelectronic analysis reveals that the heterojunction device is virtually blind to light illumination with wavelength longer than 280 nm, but is highly sensitive to 254 nm light with very good stability and reproducibility.

A series of sp(2) carbon materials with different specific surface area (SSA) and controlled pore size distribution (PSD) were synthesized at large scale through a facile and low-cost method. The SSA and PSD of these carbon materials were controlled by using different carbon sources and preparation methods. With different total and effective SSA (E-SSA) and PSD, the impacts on their capacitance performance were investigated thoroughly, which demonstrated that both E-SSA and PSD played the most important roles in their capacitance performance. Furthermore, theoretical modeling was performed, and the results are in agreement with the experimental results for the influence of E-SSA and PSD on their capacitance performance. Based on these, a general model using the slit/cylindrical NL-DFT approach is proposed for the estimation of the specific capacitance of sp(2) carbon materials, which offers a simple but reliable method to predict the capacitance performance of these materials, thus speeding up the design and screening of the materials for high-performance supercapacitor and other surface area related devices.

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It has been a great challenge to achieve the direct light manipulation of matter on a bulk scale. In this work the direct light propulsion of matter is observed on a macroscopic scale using a bulk graphene-based material. The unique structure and properties of graphene, and the novel morphology of the bulk three-dimensional linked graphene material make it capable not only of absorbing light at various wavelengths but also of emitting energetic electrons efficiently enough to drive the bulk material, following Newtonian mechanics. Thus, the unique photonic and electronic properties of individual graphene sheets are manifested in the response of the bulk state. These results offer an exciting opportunity to bring about bulkscale light manipulation with the potential to realize long-sought applications in areas such as the solar sail and space transportation driven directly by sunlight.U sing beams of light, scientists have been able to trap 1 , move 2 , levitate 3 and even pull 4 small objects (such as atoms and molecules, living cells and viruses, and micro/nanoscopic particles) on the microscopic scale, as well as nano/micrometre-sized graphene sheets 5-7 on a small spatial scale, typically on the order of hundreds of micrometres 8 . There have also been reports of efforts to enlarge the optical manipulation distance by harnessing strong thermal forces 9 , and also the robust manipulation of airborne micro-objects photophoretically with a bottle beam 10 . Furthermore, the rotation and motion of a millimetre-sized graphite disk by photoirradiation has been realized with the graphite levitated magnetically 11 . If these optical operations were to be achieved with large objects on a macroscopic spatial scale, significant applications such as the long-sought direct optical manipulation of macroscale objects (including the proposed solar sail and space transportation via laser or beam-powered propulsion) could be realized. To acquire the required energy and momentum for propulsion, two main mechanisms have been proposed: the use of a laser to superheat a propellant (or air), which then provides propulsion in the same manner as a conventional rocket 4,12,13 , or obtaining propulsion directly from light pressure (radiation pressure) acting on a light sail structure (as with the IKAROS spacecraft) 14,15 .It has been a great challenge to realize the intrinsic properties of single-layer graphene in the bulk state, because stacking of the graphene sheets diminishes most of its properties (electronic, photonic and even mechanical). In this Article, we show that if graphene sheets are assembled in the proper manner into the bulk state, the resulting bulk material not only can retain the intrinsic properties of the individual graphene sheets, but also allows their manifestation on a macroscopic scale. Here, we demonstrate the directly lightinduced macroscopic propulsion and rotation of a bulk graphene sponge material with dimensions on the scale of a centimetre and milligram weight. The mechanism behind this novel phenomenon ...

In this review, supramolecular catalysis refers to the integration of catalytic process with molecular self-assembly driven by noncovalent interactions, and dynamic assemblies are the assemblies that form and dissipate reversibly. Cells extensively employ supramolecular catalysis and dynamic assemblies for controlling their complex functions. The dynamic generation of supramolecular assemblies of small molecules has made a considerable progress in the last decade, though the disassembly processes remain underexplored. Here, we discuss the regulation of dynamic assemblies via self-assembly and disassembly processes for therapeutics and diagnostics. We first briefly introduce the self-assembly and disassembly processes in the context of cells, which provide the rationale for designing approaches to control the assemblies. Then, we describe recent advances in designing and regulating the self-assembly and disassembly of small molecules, especially for molecular imaging and anticancer therapeutics. Finally, we provide a perspective on future directions of the research on supramolecular catalysis and dynamic assemblies for medicine.