Synthesis Of Nanoporous Carbon Research Articles

Synthesis of Nano Porous Carbon derived from Vinasses Wastes for Crystal Violet Adsorption Application

An approach to removing crystal violet (CV) dye from aqueous solutions was investigated by nano porous carbon (NC) derived from vinasse waste. The NC was prepared via pyrolysis carbonization and potassium hydroxide chemical activation process. The NC was characterized by TGA, FTIR, and BET analysis. The optimal condition of the NC was used to adsorb CV dye in aqueous solutions at room temperature. Different initial CV concentrations and contact times were investigated to find the effect of these parameters. The NC was found efficient and can be used as a feasible alternative for removing CV dye from aqueous solutions. The NC was synthesized at activation temperature of 900 °C and the 1:1 precursor - activator (KOH) ratio provided the pore size of 3.285 nm and the maximum surface area 1,018 m2/g, which was an optimal condition for the crystal violet adsorption. Crystal violet was highly adsorbed within 5 minutes and then was equilibrium within 30 minutes of the contact time. The amount of dye ion adsorbed onto adsorbent was 3.3, 7.2, 11.2, and 19.1 mg/g, respectively.

Synthesis of Nanoporous Carbon for Fast Uptake of Cr(VI) and Ni(II) from Aqueous Solution.

Nanoporous carbon (NPC), based on organic xerogel compounds, was prepared at 650 °C pyrolysis temperature by sol-gel method from pyrogallol and formaldehyde (PF-650) mixtures in water using picric acid as a catalyst. The performance of NPC was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction and nitrogen porosimetry. The metal uptake characteristics were explored using effective parameters including pH, contact time, initial metal ion concentration, and temperature. Better adsorption of Cr(VI) and Ni(II) was observed at pH 2 and 4, respectively. The Langmuir model gave the better fit for Cr(VI), whereas for Ni(II), the Freundlich model is better than the other models. The kinetic studies revealed that the adsorption is fast and its data are well fitted by the pseudo-second-order kinetic model. The thermodynamic properties, i.e., ΔG°, and ΔS°, showed that adsorption of Cr(VI) and Ni(II) onto NPC was endothermic, spontaneous and feasible in the temperature range of 300 to 328 K.

Chemical-free fabrication of N, P dual-doped honeycomb-like carbon as an efficient electrocatalyst for oxygen reduction

Heteroatom-doped nanoporous carbons are now emerging as alternatives to platinum and its alloys as electrocatalysts to facilitate oxygen reduction reaction in metal-air batteries and fuel cells. However, the synthesis of nanoporous carbons usually involve in complicated procedures and intensive chemicals, which may dramatically raise their manufacture cost that even surpasses that of precious platinum. Herein, we demonstrate the single-step, chemical-free fabrication of N, P dualdoped honeycomb carbon that has hierarchically porous structure and oxygen electrocatalysis activity close to the benchmark Pt/C. This material was fabricated through the direct pyrolysis of popcorn in a static, semi-opened environment. With this strategy, nitrous and phosphoric groups from proteins and phosphates within the popcorn are condensed with graphitic matrix to form NC and PC bonds, and pyrolysis byproducts (such as H2O and CO2) can etch disordered carbon domains to form hierarchical pores and edge carbons. Practical test of this honeycomb carbon as air electrode of a primary Zn-air battery shows an open-circuit potential of 1.44V and peak power density of 36.6mWcm−2 that is even better than Pt/C. The impact of this work is that it will facilitate the targeted design and cost-saved fabrication of metal-free catalysts for electrocatalytic applications.

Synthesis of nano-porous carbon and nitrogen doped carbon dots from an anionic MOF: a trace cobalt metal residue in carbon dots promotes electrocatalytic ORR activity

Synthesis of nanoporous carbon (NPC-1) and N-doped C dots (NCD-1) has been reported from an anionic MOF. Co doping in NCD-1 enhances electrocatalytic ORR activity.

Synthesis of Nano-Porous Carbon from Cellulosic Waste and its Application in Water Disinfection

The present study deals with the preparation of new cellulosic catalyst materials, viz. paper and textile industry waste. Activated nano-carbons were prepared from these waste materials using thermo-chemical method. Nano-silver particles (AgNP) were embedded into the synthesized carbons to incorporate antimicrobial properties. The catalyst materials were characterized using FESEM-EDX, XRD, FTIR, etc. The characterization results showed that the materials were nanoporous and silver was uniformly distributed throughout the catalyst. The suitability of the catalyst as an antimicrobial agent was studied using pour plate technique. The main advantages of the disinfecting materials over conventional materials were: (i) only small quantities (mg) of catalysts are required to deactivate microorganism for up to 1 litre of water; (ii) time required for more than 99% disinfection is less (60 min); (iii) carbon has been synthesized from cellulosic wastes which otherwise would pollute the environment, hence it is a waste recycling process. The carbons exhibited more than 99% E. coli removal within 60 min.

Effect of temperature on the synthesis of nanoporous carbon from copper/carbon thin films to nanoporous carbon for sensing applications

Over the last few years, a broad panel of carbon materials was proposed for sensing applications. Among these materials, nanoporous carbon (np-C) is of particular interest due to its high specific surface area and low fabrication cost. In this contribution, the synthesis of np-C thin films using an approach combining the growth of copper/carbon nanocomposite thin films by co-sputtering followed by a selective wet etching of copper in nitric acid is studied. By adjusting the deposition conditions (e.g., powers applied to the sputtering targets, deposition temperature) of the nanocomposite thin films, it is shown that the pore size and the structure of the carbon skeleton can be modified. Furthermore, the possibility of integrating such nanoporous materials in field effect transistors for sensing application is also demonstrated.

Synthesis of Nanoporous Carbon–Cobalt‐Oxide Hybrid Electrocatalysts by Thermal Conversion of Metal–Organic Frameworks

Nanoporous carbon-cobalt-oxide hybrid materials are prepared by a simple, two-step, thermal conversion of a cobalt-based metal-organic framework (zeolitic imidazolate framework-9, ZIF-9). ZIF-9 is carbonized in an inert atmosphere to form nanoporous carbon-metallic-cobalt materials, followed by the subsequent thermal oxidation in air, yielding nanoporous carbon-cobalt-oxide hybrids. The resulting hybrid materials are evaluated as electrocatalysts for the oxygen-reduction reaction (ORR) and the oxygen-evolution reaction (OER) in a KOH electrolyte solution. The hybrid materials exhibit similar catalytic activity in the ORR to the benchmark, commercial, Pt/carbon black catalyst, and show better catalytic activity for the OER than the Pt-based catalyst.

Synthesis of nanoporous carbons from mixtures of coal tar pitch and furfural and their application as electrode materials

Synthetic nanoporous carbons are prepared by polymerization of mixtures containing coal tar pitch and furfural in different proportions, followed by carbonization of obtained solid product and steam activation of the carbonizate. The chemical composition of the initial mixture significantly affects the physicochemical properties (surface area, pore structure, electro resistance and amount of oxygen-containing groups on the surface) of the obtained materials. The incorporation of oxygen in the precursor mixture by means of furfural, has a strong influence in the synthetic step; increasing the furfural content facilitates the formation of a solid product characterized by a large oxygen content. Moreover, the solid product is more reactive towards activation as the furfural content increases, giving rise to nanoporous carbons with large surface areas and unique chemical features (high density of oxygen functionalities of basic nature). These nanoporous carbons have been investigated as electrodes in electrochemical applications.

Synthesis of nanoporous carbons by an in situ template approach

Synthesis of nanoporous carbons by an in situ template approach

Synthesis of Nanoporous Carbon as a Gas Adsorbent by Reverse Replication Process of Silica Template

Porous carbon with high surface area and pore volume was prepared by a reverse replication process and its toluene equilibrium adsorption behavior was investigated. The preparation process of the porous carbon was composed of following sub-processes in series: synthesis and template preparation of silica gel, impregnation and polymerization of DVB monomer in silica template, carbonization of DVB polymer in a silica-polymer composite, and HF-assisted selective etching of silica in carbon-silica composite. The prepared porous carbon was nano porous and had ultrahigh specific surface area (2007 ㎡/g) and large pore volume (3.07 ㎤/g). The nanoporous carbon showed rapid toluene adsorption rate and good toluene adsorption capacity, compared with a commercial Y-type zeolite. In the present study, a reverse replication process to prepare nanoporous carbons will be introduced and its application potential as a gas adsorbent will be discussed.

Novel Silica-Sol Mediated Synthesis of Nanoporous Carbons

ABSTRACTNew preparative methods for the synthesis of nanoporous carbons using silica particles as templates will be presented. Gellation of resorcinol and formaldehyde in the presence of silica sol particles generated RF gel-silica nanocomposite. Carbonization followed by HF etching of silica templates generated nanoporous carbons with pore size ranging 10 ∼ 100 nm. When silica particles stabilized with surfactant were used as templates, uniform ∼ 10 nm pore-sized carbons have been formed. These nanoporous carbons exhibited excellent adsorption capacity for dyes.