Large Mesoporous Carbon Research Articles

Nitrogen doped large mesoporous carbon for oxygen reduction electrocatalyst using DNA as carbon and nitrogen precursor

By using herring sperm DNA as carbon and nitrogen precursor and commercial hydrophilic nano-CaCO3 as hard-template, a one step and green method to synthesize nitrogen doped large mesoporous carbon (N-LMC) is presented. Transmission electron microscopy (TEM), nitrogen adsorption–desorption and X-ray photoelectron spectra (XPS) were employed to confirm the characterizations of N-LMC. The as-prepared material exhibited higher electrocatalytic activity for the oxygen reduction reaction (ORR) than LMC. Moreover, the influence of different amounts of N-bonding configurations formed at different carbonization temperatures in N-LMC for the ORR was researched. Results indicated that N-LMC treated at 800°C (N-LMC-800) with high amounts of pyridinic N and graphitic N showed improved electrocatalytic activity for the ORR.

Novel Approach for the Synthesis of Nanocrystalline Anatase Titania and Their Photovoltaic Application

High surface area titania with crystalline anatase walls has been synthesized using ordered large mesoporous carbon as a template. The pore structure of mesoporous carbon is infiltrated with titanium tetraisopropoxide solution at room temperature and the mixture is subjected to heat treatment at in presence of air to complete removal of the template. The prepared crystalline anatase frameworks are characterized by XRD, N2adsorption and HR-TEM. The nitrogen adsorption-desorption analysis of the prepared anatase titania particles exhibits BET specific surface area of 28 m2/g. The dye-sensitized solar cells performance of this anatase titania material has been tested and energy conversion efficiency of 3.0% is achieved under AM 1.5 sunlight. This work reports a new approach for fabrication of nanocrystalline anatase titania by simple hard templating technique for the first time and their applications for dye-sensitized solar cell.

Large pore volume mesoporous copper particles and scaffold microporous carbon material obtained from an inorganic–organic nanohybrid material, copper-succinate-layered hydroxide

Copper-succinate-layered hydroxide (CSLH), a new nanohybrid material, was synthesized as an inorganic–organic nanohybrid, in which organic moiety was intercalated between the layers of a single cation layered material, copper hydroxide nitrate. Microporous scaffold carbon material was obtained by thermal decomposition of the nanohybrid at 500°C under argon atmosphere followed by acid washing process. Furthermore, the heat-treated product of the nanohybrid at 600°C was ultrafine mesoporous metallic copper particles. The results of this study confirmed the great potential of CSLH to produce the carbon material with large surface area (580m2/g) and high pore volume copper powder (2.04cm3/g).

Metal-Free Counter Electrode for Efficient Dye-Sensitized Solar Cells through High Surface Area and Large Porous Carbon

Highly efficient, large mesoporous carbon is fabricated as a metal-free counter electrode for dye-sensitized solar cells. The mesoporous carbon shows very high energy conversion efficiency of 7.1% compared with activated carbon. The mesoporous carbon is prepared and characterized by nitrogen adsorption, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The nitrogen adsorption data reveals that the material possesses BET specific surface area ca.1300 m2/g and pore diameter 4.4 nm. Hexagonal rod-like morphology and ordered pore structure of mesoporous carbon are confirmed by electron microscopy data. The better performance of this carbon material is greatly benefited from its ordered interconnected mesoporous structure and high surface area.

Electrochemical property and electroanalytical application of large mesoporous carbons

This article reports on the electrochemical property of large mesoporous carbons (LMC) synthesized using nano-CaCO 3 as a template and sucrose as a carbon precursor. Though a simple preparation method for LMC, the LMC modified glassy carbon electrode (LMC/GCE) exhibited good electrochemical activity for some common electroactive compounds, such as ascorbic acid (AA), uric acid (UA), epinephrine (EP) and tryptophan (Trp). The unique properties of LMC were also compared with those of carbon nanotubes (CNT), and the results showed that the LMC possessed a much better property than CNT. In addition, the LMC/GCE was also used to analyze the β-nicotinamide adenine dinucleotide (NADH) and hydrogen peroxide (H 2O 2) and showed a high sensitivity and low detection limit. Based on a simple preparation method and good electrochemical property, the LMC represents a new class of carbon electrode for electrochemical sensor applications.

Nano-CaCO3as template for preparation of disordered large mesoporous carbon with hierarchical porosities

A series of large mesoporous carbons (LMC, 20–50 nm) with hierarchical porosities has been prepared using commercially available CaCO3 nanoparticles as a template, formaldehyde (PF) resin as carbon precursor, and HCl solution for removing the template. During the carbonization process, the CaCO3 template decomposes releasing CO2 which serves as an activating agent to active the carbon materials producing micropores and mesopores as well as enlarging pore sizes. This effect can be named as the “CO2 inner-activation effect”, which is proved by comparing the carbon yield, N2 adsorption/desorption isotherms, pore-size distribution and textual parameters of carbon materials carbonized at two critical temperatures, namely, 900 °C (higher than the pyrolysis temperature of CaCO3) and 650 °C (lower than the pyrolysis temperature of CaCO3). Our results show that the LMC samples prepared at different ratios of CaCO3 to PF have BET surface areas ranging from 503 to 1215 m2 g−1, and pore volumes ranging from 1.8 to 9.0 cm3 g−1. This one-step carbonization method with a CO2 inner-activation effect provides a novel route to prepare large mesoporous carbons and hierarchical porous carbon materials.

Templated nanoscale porous carbons

This manuscript reviews key developments in the important and rapidly expanding area of templated porous carbons. The porosity covered ranges from microporous to mesoporous and macroporous carbons. Two modes of templating, using so-called hard and soft templates, are covered. In particular, for hard templating, zeolite templating generates microporous carbons, mesoporous silicates yield mesoporous carbons, while colloidal particles are replicated to large mesoporous and macroporous carbons. Soft-templating, a more recent phenomenon, mainly generates mesoporous carbons. The full range of pore sizes can therefore now be accessed using hard and soft templates to generate highly ordered nanoscale carbons with well-defined and optimised textural properties. The research area has seen rapid and important developments over the last few years, and this review aims to present the more significant advances.

ChemInform Abstract: Extremely Large Mesoporous Carbon Fibers Synthesized by the Addition of Rare Earth Metal Complexes and Their Unique Adsorption Behaviors.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Extremely large mesoporous carbon fibers synthesized by the addition of rare earth metal complexes and their unique adsorption behaviors

Extremely highly mesoporous activated carbon fibers (see Figure) have been synthesized for the first time from pitch fibers containing rare earth metal complexes. These fibers have potential applications in the purification of drinking water, for example, owing to their ability to absorb giant molecules such as humic acid. Investigations of the absorption behavior of the fibers are reported. fig.magnified image