Carbon is anything but a new material, yet ubiquitously applicable for many catalytic transformations in modern organic chemistry. It is highly versatile, as it occurs as modifications abundantly available as 1− 3D carbonaceous materials due to technical progress. In addition, materials such as activated charcoal, ordered mesoporous carbon (OMC), graphite and graphene (oxide), carbon nanotubes (CNTs), nanospheres (nanoonions, fullerenes), and many others are no "innocent" supports, as demonstrated by many recent publications within the revitalized field of "carbocatalysis". By nature, carbon scaffolds offer a perfect link between nanoscaled matter and organic molecules, which makes them an ideal cornerstone for molecular catalysts. Apart from this inherent chemical significance, the physical properties (e.g., different conductivity) are equally important for the performance of heterogeneous or immobilized homogeneous catalysts. Careful selection of the carbon scaffold enables control of reactivity by tuning the electronic interactions of active sites with the support or among each other. Moreover, separation and recycling of "heterogenized" catalysts can be further improved by rendering carbon "magnetic", that is, by incorporation of magnetic particles or by coating metal nanomagnets with graphene-like shells. Altogether, tuning the properties of carbon supports might lead to catalysts tailored not only in matters of reactivity (electron shuttle), but also to down-to-earth problems such as purification (magnetic separation and recycling). This critical review will highlight how far such concepts have already been implemented in the design of "heterogenized" catalysts and is meant to widen the perspectives where certain concepts have yet to be realized.
A mussel-inspired synthetic adhesive based on dopamine containing methacrylate copolymers was developed to bond polymers to metal surfaces at an adhesion strength of up to 20 MPa for bulk samples.
Magnetic nanoparticle dispersions are traditionally made from superparamagnetic materials since the absence of magnetic particle-particle attraction under normal conditions (no external field) easily allows preparation of stable dispersions. For inductive heating in medicinal chemistry or material science, however, the much higher magnetization of ferromagnetic metals over the currently used oxides is attractive. Traditional attempts to prepare stable dispersions of ferromagnetic particles, however, failed since the strong magnetic particle-particle attraction usually overcomes repulsive effects from surfactants or steric stabilizers (typically polymers). In the present work, we demonstrate how the direct, covalent attachment of highly charged polymers can circumvent stabilizer detachment and loss, and permits preparation of stable dispersions of ferromagnetic particles. More specifically, carbon-coated metal nanoparticles were covalently functionalized with positively charged polymer brushes via surface initiated atom transfer radical polymerization (SI-ATRP). Particle size distributions with an average diameter of 24 nm provided a ferromagnetic liquid with unprecedented stability in water over several months. The stability was discussed by comparison of the potentials of nonfunctionalized and modified nanomagnets within a modified Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. Measurements for inductive heating at different frequencies and various field strengths showed an average specific absorption rate of 360 W g À1 . Altogether, this suggests that efficiently stabilized dispersions of ferromagnetic nanoparticles could be an alternative to superparamagnetic iron oxide particles in a number of applications.
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