This review focuses on the synthesis, protection, functionalization, and application of magnetic nanoparticles, as well as the magnetic properties of nanostructured systems. Substantial progress in the size and shape control of magnetic nanoparticles has been made by developing methods such as co-precipitation, thermal decomposition and/or reduction, micelle synthesis, and hydrothermal synthesis. A major challenge still is protection against corrosion, and therefore suitable protection strategies will be emphasized, for example, surfactant/polymer coating, silica coating and carbon coating of magnetic nanoparticles or embedding them in a matrix/support. Properly protected magnetic nanoparticles can be used as building blocks for the fabrication of various functional systems, and their application in catalysis and biotechnology will be briefly reviewed. Finally, some future trends and perspectives in these research areas will be outlined.

Nanocasting is a powerful method for creating materials that are more difficult to synthesize by conventional processes. We summarize recent developments in the synthesis of various structured porous solids, covering silica, carbon, and other nonsiliceous solids that are created by a nanocasting pathway. Structure replication on the nanometer length scale allows materials' properties to be manipulated in a controlled manner, such as tunable composition, controllable structure and morphology, and specific functionality. The nanocasting pathway with hard templates opens the door to the design of highly porous solids with multifunctional properties and interesting application perspectives.

A polymer gel derived from resorcinol and formaldehyde can be prepared in around 5 min using lysine as polymerization catalyst and nitrogen source. After pyrolysis of this polymer gel, a new type of nitrogen‐containing carbon monolith was obtained (see figure), which exhibits the highest CO2‐adsorption capacity to date of up to 3.13 mmol g−1 at room temperature.

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Dopamine is an excellent and flexible agent for surface coating of inorganic nanoparticles and contains unusually high concentrations of amine groups. In this study, we demonstrate that through a controlled coating of a thin layer of polydopamine on the surface of α-Fe(2)O(3) in the dopamine aqueous solution, followed by subsequent carbonization, N-doped carbon-encapsulated magnetite has been synthesized and shows excellent electrochemical performance as anode material for lithium-ion batteries. Due to the strong binding affinity to iron oxide and excellent coating capability of this new carbon precursor, the conformal polydopamine derived carbon is continuous and uniform, and its thickness can be tailored. Moreover, due to the high percentage of nitrogen content in the precursor, the resulting carbon layer contains a moderate amount of N species, which can substantially improve the electrochemical performance. The composites synthesized by this facile method exhibit superior electrochemical performance, including remarkably high specific capacity (>800 mA h g(-1) at a current of 500 mA g(-1)), high rate capability (595 and 396 mA h g(-1) at a current of 1000 and 2000 mA g(-1), respectively) and excellent cycle performance (200 cycles with 99% capacity retention), which adds to the potential as promising anodes for the application in lithium-ion batteries.

The durability of electrode materials is a limiting parameter for many electrochemical energy conversion systems. In particular, electrocatalysts for the essential oxygen reduction reaction (ORR) present some of the most challenging instability issues shortening their practical lifetime. Here, we report a mesostructured graphitic carbon support, Hollow Graphitic Spheres (HGS) with a specific surface area exceeding 1000 m(2) g(-1) and precisely controlled pore structure, that was specifically developed to overcome the long-term catalyst degradation, while still sustaining high activity. The synthetic pathway leads to platinum nanoparticles of approximately 3 to 4 nm size encapsulated in the HGS pore structure that are stable at 850 °C and, more importantly, during simulated accelerated electrochemical aging. Moreover, the high stability of the cathode electrocatalyst is also retained in a fully assembled polymer electrolyte membrane fuel cell (PEMFC). Identical location scanning and scanning transmission electron microscopy (IL-SEM and IL-STEM) conclusively proved that during electrochemical cycling the encapsulation significantly suppresses detachment and agglomeration of Pt nanoparticles, two of the major degradation mechanisms in fuel cell catalysts of this particle size. Thus, beyond providing an improved electrocatalyst, this study describes the blueprint for targeted improvement of fuel cell catalysts by design of the carbon support.

In heterogeneous catalysis, supports play a crucial role in modulating the geometric and electronic structure of the active metal phase for optimizing the catalytic performance. A γ-Al2O3 nanosheet that contains 27% pentacoordinate Al(3+) sites can nicely disperse and stabilize raft-like Pt-Sn clusters as a result of strong interactions between metal and support. Consequently, there are strong electronic interactions between the Pt and Sn atoms, resulting in an increase in the electron density of the Pt sites. When used in the propane dehydrogenation reaction, this catalyst displayed an excellent specific activity for propylene formation with >99% selectivity, and superior anti-coking and anti-sintering properties. Its exceptional ability to maintain the high activity and stability at ultrahigh space velocities further showed that the sheet construction of the catalyst facilitated the kinetic transfer process.

Magnetic, highly porous ordered carbon of the CMK‐3 and CMK‐5 type and with pure carbon or carbon–nitrogen framework were nanoengineered by a sequence of bulk manipulation steps. The materials can be used as efficient magnetic adsorbents (see picture) or catalysts, but applications going far beyond these can be envisaged.