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Mesoporous carbons prepared using a templating method under different carbonization temperatures are sulfonated with concentrated H₂SO₄. Without the moving of silica template carbon–silica composites were prepared, which can maintain the pore structure well during sulfonation reaction process. The resultant samples are characterized using nitrogen adsorption, transmission electron microscope, field-emission scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy, and elemental analysis techniques. The catalytic performances of the sulfonated carbons and composites are evaluated by esterification reaction of methanol with acetic acid. The results show that a low-temperature carbonization process is favorable for improving the reaction conversion of acetic acid. In addition, the sulfonated carbon–silica composites show a higher acetic acid conversion than the sulfonated mesoporous carbons.

We presented here three carbon-nanomaterials-based modified glassy carbon electrodes (GCE) with Ni–Ag nanohybrid nanoparticles (NPs) deposited upon, including single-wall carbon nanotubes (SWCNTs), multi-wall carbon nanotubes (MWCNTs) and the mesoporous carbons (MPCs), and compared their morphology effects on both Ni–Ag deposition quality and electrocatalytic performances toward Glu oxidation. After being deposited with Ni–Ag NPs, a homogenous surface with very small Ni–Ag NPs was obtained for Ni–Ag/SWCNTs/GCE, while heterogeneous, coarse surfaces with obvious embedment with large Ni–Ag particles were observed for both Ni–Ag/MWCNTs/GCE and Ni–Ag/MPC/GCE. All three modified electrodes were well characterized in terms of surface morphology, electron transfer rate, hydrophilicity, interference resistance, stability, electrocatalytic behaviors as well as practicability in real samples, based on which Ni–Ag/SWCNTs/GCE was always proved to be more advantageous over other two composite electrodes. Such advantage of Ni–Ag/SWCNTs/GCE was attributed to its desirable surface morphology good for Ni–Ag deposition and exposure of as many active sites as possible to Glu oxidation, leading to the extraordinary electrocatalytic performance.

Novel bismuth nanoparticle-modified mesoporous carbon (MPC) was successfully prepared on a glassy carbon electrode (Bi@MPC/GCE) for the adsorptive stripping voltammetric determination of nickel by complexing with dimethylglyoxime (DMG). The presence of MPC obviously improved the properties of Bi particles like the electron transfer ability, particle size and hydrophicility, important parameters to achieve preferable analytical performances of Bi@MPC/GCE toward Ni(II). The best electrochemical behaviors of Bi@MPC/GCE was obtained for the stripping determination of Ni(II), compared with electrodes individually modified with Bi and MPC. The synergic effect between metallic Bi and ordered MPC (forming a 3D array like Bi microelectrodes) made major contribution to such improved electrochemical properties of Bi@MPC/GCE for Ni(II) sensing. The good linear analytical curve was achieved in a Ni(II) concentration range from 0.1$\mu$M to 5.0$\mu$M with a correlation coefficient of 0.9995. The detection limit and sensitivity were calculated to be 1.2nM ($S∕N=3$) and 1410$\mu$AmM${}^{-1}$cm${}^{-2}$, respectively. The new method was successfully applied to Ni(II) determination in soybean samples with recoveries higher than 99% and proved to be a simple, efficient alternative for Ni(II) monitoring in real samples.

Oxygen evolution reaction (OER) is of great importance in splitting water. However, the sluggish OER kinetics at the anode severely hinders the H₂ evolution at the cathode which is a crucial procedure for energy storage. Herein, we report the synthesis of a new OER catalyst of Co(OH)_x(WO${}_4{)}_y$via a one-step hydrothermal method, where the incorporation of WO${}_4^{2-}$ as a condenser greatly enhanced the electrocatalytic activity of Co(OH)₂ toward OER. Moreover, the introduction of mesoporous carbon (MC) further improves the electrocatalytic performance of Co(OH)_x(WO${}_4{)}_y$ by forming the nanocomposites of Co(OH)_x(WO${}_4{)}_y$/MC. The synergism between Co(OH)₂ and WO${}_4^{2-}$ and the synergistic catalytic effect of Co(OH)_x(WO${}_4{)}_y$ and MC majorly contributed to the apparently enhanced electrocatalysis of Co(OH)_x(WO${}_4{)}_y$/MC toward OER. This work provides an efficient strategy to improve the electrocatalytic activity of Co(OH)₂ by introducing WO${}_4^{2-}$ and forming nanocomposites between Co(OH)_x(WO${}_4{)}_y$ and MC for low-cost, convenient and highly efficient water oxidation.

Co doped mesoporous carbon composites (MC–Co) have been synthesized at different carbonization temperatures via evaporation-induced multicomponent co-assembly strategy. The nanostructures and chemical compositions of MC–Co composites were characterized by transmission electron microscope (TEM), scanning electron microscope (SEM) and X-ray diffraction analysis (XRD), etc. Their electromagnetic and microwave absorption properties were investigated in the frequency ranging from 2 GHz to 18 GHz. By the measurement of electromagnetic parameters and theoretical simulation of reflection loss (RL), the results showed that the minimum RL value of the optimum composite MC–Co-800 reached up to -41.9 dB at 13.5 GHz with a thickness of only 1.80 mm, and the effective absorption bandwidth (< -10 dB) is 4.4 GHz (from 11.4 GHz to 15.8 GHz). This work demonstrated that the optimum carbonization temperature of the obtained composites is 800°C, which is critical to its electromagnetic properties. The excellent microwave absorption properties can be attributed to dielectric loss, Ohmic loss, and characteristic impedance matching. Therefore, the as-synthesized composites could be acted as a candidate of microwave absorber, especially for the light weight demand.

Nitrogen-doped mesoporous carbon spheres (NMCSs) supporting anatase TiO₂ (NMCSs–TiO₂) were prepared by a simple two-step solvothermal approach. The characterizations for the physicochemical properties of prepared samples under different solvothermal temperatures were carried out by X-ray diffraction (XRD) analyses, scanning electron microscopy (SEM), transmission electron microscopy (TEM), N₂ adsorption–desorption (Brunauer–Emmett–Teller (BET) measurements), Fourier transform infrared (FT-IR) spectroscopy, Raman scattering and UV-Vis diffuse reflectance spectra, were combined in order to determine the crystal phase and grain size, shape, degree of mesoporous carbon incorporation, and nature of the resultant oxycarbide chemical bonding on the surface and in the bulk. The high relative photocatalytic activity of NMCSs–TiO₂ nanoparticle was evaluated through a study of the decomposition of phenol under visible-light excitation.

We report engineered iron-based nanoparticles supported on cagelike mesoporous carbon that leaves its most mesopores empty to retain an open pore network and are expected to be efficient catalyst with fast molecular diffusion/transportation. The nano-scale iron-based particle inlayed in mesoporous carbon catalyst was obtained via the introduction of N atoms as an anchor. Results of X-ray diffraction, N₂ sorption and transmission electron microscopy showed that the cagelike mesoporous structure of the carbon matrix was retained during catalyst preparation and iron-based nanoparticles were spatially dispersed on the mesoporous carbon. Importantly, it was found that the obtained iron-based nanoparticles inlayed into mesoporous carbon with a low Fe loading of 1.26wt.% was an appropriate catalyst for the benzene hydroxylation to phenol using H₂O₂ as the oxidant. At a low temperature of 30^∘C, 19.4% conversion to benzene and 14.6% phenol yield were obtained; in addition, the catalyst could be recycled at least four times.

An efficient route is proposed to synthesize magnetic nitrogen-doped mesoporous carbon (Fe₃O₄/NMC) composites. The nitrogen-doped mesoporous carbon (NMC) material was prepared using a melamine–formaldehyde resin as nitrogen and carbon source and fumed silica as a template via a template method, and Fe₃O₄ nanoparticles were introduced via an in situ formation method. The effects of the loading amount of Fe₃O₄ on the morphology, structure, magnetic properties and adsorption performance of the Fe₃O₄/NMC composites were investigated. Fe₃O₄ nanoparticles dispersed well on the surface and inside the NMC, and the Fe₃O₄/NMC remained a mesoporous structure. Fe₃O₄/NMC exhibited superparamagnetic behavior, and the maximum saturation magnetization was 30.1emu/g. Fe₃O₄/NMC had a decreased specific surface area and pore volume compared to NMC, but the Fe₃O₄/NMC composites still showed excellent adsorption capacity for Ag(I), reaching 71.9mg/g. The adsorption efficiency of Fe₃O₄/NMC remained at 90.3% of the initial removal capability after five cycles, which demonstrated the potential large-scale industrial applications of these composites.

Mechanical alloying is used to prepare the Co${}_{0.9}$Cu${}_{0.1}$Si alloy. Mesoporous silicon SBA-15 is employed as the template to synthesize mesoporous carbon CMK-3. For the purpose of improving the electrochemical properties of Co${}_{0.9}$Cu${}_{0.1}$Si alloy, Co${}_{0.9}$Cu${}_{0.1}\mathrm{\text{Si}}+x$ CMK-3 ($x=3\%$, 6%, 9% and 12% mass fraction) alloys are fabricated via ball-milling. As the negative electrodes of Ni–MH batteries, the discharge capacities of alloys are tested by the LAND CT2001A tester and three-electrode system. Finally, the composite alloys show different properties for hydrogen storage. A maximum discharge capacity (558.7mAh/g) is achieved for Co${}_{0.9}$Cu${}_{0.1}\mathrm{\text{Si}}+6\%$ CMK-3 electrode. Superfluous CMK-3 is not beneficial to enhance the discharge capacity of Co${}_{0.9}$Cu${}_{0.1}$Si alloy. Moreover, Co${}_{0.9}$Cu${}_{0.1}\mathrm{\text{Si}}+x$ CMK-3 electrodes exhibit better corrosion and oxidation resistance, which leads to higher capacity retention for CMK-3/Co${}_{0.9}$Cu${}_{0.1}$Si composites. The comparative studies on HRD and kinetic properties of Co${}_{0.9}$Cu${}_{0.1}$Si and Co${}_{0.9}$Cu${}_{0.1}\mathrm{\text{Si}}+6\%$ CMK-3 are also conducted. The $R_{\mathrm{\text{ct}}}$ of Co${}_{0.9}$Cu${}_{0.1}$Si alloy reduces and $I_0$ increases after doping of CMK-3. The special structural characteristics and higher conductivity of CMK-3 can offer more electrochemical active sites and accelerate hydrogen diffusion. Accordingly, the electrochemical activity and kinetic properties are enhanced for CMK-3/Co${}_{0.9}$Cu${}_{0.1}$Si composites.

The present paper studies a kind of mesoporous carbon (MC) with high electrochemical performance, which was prepared by vapor infiltration method. The microstructure and electrochemical properties of the mesoporous carbon were investigated by transmission electron microscopy (TEM), nitrogen adsorption–desorption isotherms, cyclic voltammetry (CV), constant current charge–discharge cycling (CD), and the long-term stability test. The results indicated that the mesoporous carbon has an ordered mesoporous structure, with pore size of about 3.87 nm and surface areas of 1087 m² ⋅ g^-1. The cyclic voltammetry curve reveals typical electrical double-layer capacitor property. After 200 cycles, the CV curves can almost be overlapped, which indicates excellent cycling stability. From the charge/discharge cycling, the specific capacitance of MC is 117 F ⋅ cm^-1 in 1.0 M KNO₃ electrolyte media at a scan rate of 1.0 mV ⋅ s^-1, which decays with increasing current density. The charge–discharge efficiency also decays with it.

Ordered mesoporous carbon film supporting vanadium oxide nanoparticles has been synthesized via ultrasound-assistant impregnation method with ordered mesoporous carbon C-FDU15 film as the host and V₂O₅ sol as the guest precursor. The hybrids exhibit type IV sorption isotherms with H2 hysteresis loop, indicating the well-retained characteristics of ordered mesoporous structure. The capacitance of the materials is enhanced with V₂O₅ loading. Particularly, the hybrids with 32.26 wt.% V₂O₅ loading yield an important capacitance of 128 F/g in 1 mol/L KNO₃ electrolyte under a potential range from -0.6 V to 0.6 V. The improved specific capacitance of the hybrids is proposed to be the combination of the double-layer capacitance of ordered porous structure and the pseudocapacitance derived from V₂O₅.

Here, a series of cellular-structured and predominantly mesoporous carbons were prepared via carbonization of glucose–fructose syrup (GFS) with sulfuric acid and subsequent calcination between 400${}^{\circ }$C and 700${}^{\circ }$C. Comparative results on the microstructure, chemical and textural properties of the newly produced carbons are presented. Furthermore, their adsorption performance for removal of acetaminophen from water was tested and it was found that the carbon calcined at 700${}^{\circ }$C has a maximum adsorption capacity (98.7mg$\cdot$g${}^{-1}$) among all samples due to its suitable textural properties (BET surface area of 418m${}^2\cdot$g${}^{-1}$ and total pore volume of 0.2cm${}^3\cdot$g${}^{-1}$). This study demonstrates the potential use of GFS as a precursor in the preparation of carbonaceous materials for removal of biologically-active micropollutants from water.