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Activated carbons are one of the most important classes of high‐surface‐area porous materials. Owing to their unique structure, low price, and large‐scale production technology, these porous carbons have been traditionally used as sorbents for eliminating contamination. In the past decade, many innovations have been seen in the synthesis, structure, applications, and theoretical and experimental methods. Herein, a comprehensive review of the up‐to‐date progress of activated carbons is presented from the viewpoint of synthetic chemistry and materials science. First, the critical textural properties are discussed, with special emphasis on the porous texture, heteroatom doping, surface functional groups, and partial graphitization. Next, the advanced synthetic strategies of activated carbons are summarized. Special attention is given to the reaction mechanism between activating agents and carbon sources, as well as the design of controlled forms and morphology. Then, their applicability in various emerging fields is covered, including supercapacitors, capacitive deionization, batteries, electrocatalysis, and carbon capture. In particular, this review highlights the potential synthesis–structure–property correlations of these porous materials. Finally, we present the future challenges and outlook for their success in energy and environmental science. [ABSTRACT FROM AUTHOR]

Asymmetric supercapacitors (ASCs) have attracted growing interest and attention in the field of supercapacitors owing to their high energy density and power density. In this work, ordered mesoporous Co3O4 samples with different pore sizes (ca. 20 nm and ca. 70 nm) are prepared via a hard template method. Flexible solid-state ASC devices based on mesoporous Co3O4 with pore size of 20 nm and activated carbon possesses a specific capacitance of 215 mF cm−2 (at 1.5 mA cm−2) and show excellent cycling performance. Electrochemical tests reveal that the mesoporous material with a larger specific surface area, that is, a smaller primary particle size, is more suitable for solid-state ASC device. The results provide a potential electrode material for ACSs. [ABSTRACT FROM AUTHOR]

Mesoporous ZnO-NiO architectures were prepared by thermal annealing of zinc-nickel hydroxycarbonate composites. The resulting architectures are shown to be assembled by many mesoporous nanosheets, and this results in a large surface area and a strong synergy between the ZnO and NiO nanoparticles. The material obtained by annealing at 400 °C was used as an electrode that responds to glucose over a wide concentration range (from 0.5 μM to 6.4 mM), with a detection limit as low as 0.5 μM, fast response time (<3 s), and good sensitivity (120.5 μA · mM · cm). [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Abstract: In this work, we report the simple solid-state formation of mesoporous In2O3 nanorods with a quasi-single-crystalline framework. The synthesis is based on controlled thermal oxidative decomposition and re-crystallization of precursor In(OH)3 nanorods obtained from a hydrothermal method without using any surfactants or organic templates. Importantly, the rod-like morphology can be completely preserved after thermal treatment. Due to the intrinsic crystal contraction, a highly mesoporous structure with high specific surface area (up to 103.1m2/g) has been created. The textual properties can be tailored by varying the annealing temperature. The gas sensing test results show that mesoporous In2O3 nanorods possess satisfactory response to dilute ethanol vapor. [Copyright &y& Elsevier]

Graphene is an excellent substrate to load nanomaterials for energy applications due to its large surface area, excellent conductivity, mechanical strength, and chemical stability. In this study, thermal exfoliated functionalized graphene sheets with good conductivity and high BET surface area are anchored with mesoporous NiO nanoplates by in situ chemical synthesis approach. Electrochemical characterization shows that functionalized graphene sheets-NiO sample exhibits a high capacity of about 700 mAh/g at a discharge current density of 100 mA/g and a good cycling ability. The high capacity and good cycling ability of functionalized graphene sheets -NiO material were attributed to the intimate interaction between the graphene sheets and NiO nanoplates. The graphene sheets not only enhance the conductivity of NiO nanoplates but also improve the structure stability of NiO nanoplates. Furthermore, the mesoporous structure of NiO nanoplates is available to the transfer of electrolyte. Such functionalized graphene sheets-NiO nanocomposite could be a promising candidate material for a high-capacity, low cost, and nontoxic anode for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Mg(OH)2 nanoplate with single-crystal structure was synthesized by a solvothermal method without using any surfactants or organic templates. MgO was obtained by annealing Mg(OH)2 at low temperature. The samples were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N2 adsorption–desorption analysis. The results indicate that MgO sample inherits the nanoplate morphology and single-crystal structure of Mg(OH)2. Moreover, MgO nanoplate has disordered mesoporous structure, large BET surface area, and high pore volume. The BET surface area and pore volume can reach up to 373.2m2/g and 0.71cm3/g. The dehydration of Mg(OH)2 during heat treatment results in the formation of mesopores. The effect of the solvothermal reaction temperature, the solvothermal reaction solvent, and the annealing temperature on the BET surface areas of MgO products was studied. [Copyright &y& Elsevier]

Abstract: The microstructures of mesoporous carbon nanofibers were characterized by scanning electron microscopy, transmission electron microscopy, nano-Raman, nitrogen adsorption–desorption and optical transmission. They possessed a high specific surface area 840m2 g−1 and a 1.07eV band gap. All mesoporous carbon nanofiber network can act as the channel material in p-type field-effect transistor devices with field-effect mobilities over 10cm2/Vs. Furthermore, mesoporous carbon nanofiber network exhibits better sensitivity and faster response to NO2 gas than that of carbon nanotubes, which makes it a promising candidate as poisonous gas sensing nanodevices. [Copyright &y& Elsevier]

A new restriction effect of hard templates for the shrinkage of mesoporous polymer results in anomalous increase of the mesopore size during carbonization. [ABSTRACT FROM AUTHOR]

Highly dispersed Pt nanoparticles were formed in the mesoporous channels of SBA-15 via direct low-temperature decomposition of H2PtCl6·6H2O by an improved solid–liquid route. During the preparation, solid H2PtCl6·6H2O turned into liquid and infiltrated the channels of SBA-15 when the temperature was above its melting point. The reaction process was analyzed by different characterizations. The results show that the solid intermediate phase, PtCl2, could not flow and assemble in the mesoporous channels during the heat-treatment; thus, it transformed into dispersed Pt nanoparticles after the reaction. Furthermore, as a nanoreactor, the mesoporous system had a nano-confinement effect on the low-temperature formation of Pt. [ABSTRACT FROM AUTHOR]

Abstract: Ordered mesoporous carbons (OMCs) with controllable pore sizes in the range of 4–10nm are prepared by a template procedure using 2D hexagonal MSU-H and 3D cubic KIT-6 as hard templates and boric acid as the pore expanding agent. The electrochemical performances of the as-synthesized OMCs as electrode materials for electrochemical double layer capacitors (EDLCs) are characterized by cyclic voltammetry (CV), galvanostatic charge/discharge (GC) and electrochemical impedance spectroscopy (EIS) experiments in 30wt% KOH electrolyte. The influence of the pore size distributions of OMCs on the electrochemical capacitive performances is discussed. The prepared OMCs exhibit good capacitive behaviors with the specific capacitance values ranging from 143 to 205.3Fg−1 at a voltage scan rate of 5mVs−1 and 81 to 86% retained at a high scan rate of 100mVs−1. OMC-M-2 shows the highest specific surface capacitance value of 27.5μFcm−2 at 5mVs−1 with a peak pore size of 7.8nm and a Brunauer–Emmet–Teller (BET) surface area of 729.3m2 g−1. The analysis of two kinds of pore symmetries of OMCs with the same pore size of about 6.5nm shows that the 3D cubic OMC exhibited superior capacitive performance than the 2D hexagonal OMC. [Copyright &y& Elsevier]

Abstract: A mesoporous carbon nanofiber-modified pyrolytic graphite electrode (MCNF/PGE) has been prepared and applied to the simultaneous electrochemical determination of dopamine (DA), uric acid (UA) and ascorbic acid (AA). The oxidation overpotentials of these biomolecules decrease significantly, the overlapping of these peaks in bare PGE is well resolved, and their anodic peak currents increase dramatically in MCNF/PGE due to the large amount of edge-plane-like defects, large surface area and especially the mesoporous structure of MCNFs. Using this method, anodic currents of DA, UA and AA are linear with their concentration in the range of 0.05–30μM, 0.5–120μM and 0.1–10mM, respectively, with detection limits of 0.02, 0.2 and 50μM. The good sensitivity and reproducibility of the proposed electrode make it be used as a good electrochemical sensor for the simultaneous determination of DA, UA and AA in real sample analysis. [Copyright &y& Elsevier]