Magnetically separable porous graphitic carbon with large surface area as excellent adsorbents for metal ions and dye

Abstract

Magnetic porous graphitic carbon (MPGC) materials were fabricated through a facile ''Solution-Solid'' route and their application as excellent adsorbents for metal ions and dye were also demonstrated. In the preparation, glucose, nickel nitrate and TEOS were selected as carbon resource, catalyst precursor and porogent, respectively. In the first step, the solution contained glucose, Ni 2+ and TEOS was treated at low temperature to impel polymerization of glucose, coordination of Ni 2+ with glucose unit and hydrolysis of TEOS simultaneous, leading to the formation of precursor (Solution process). After heating the precursors under N 2 atmosphere, the Ni-SiO 2 /carbon composites were formed (Solid process). Followed soaking with NaOH to remove SiO 2 porogent, the corresponding MPGC materials with magnetic nickel particles embedded in the graphitic carbon framework were obtained. The obtained MPGC materials show good chemical stability due to their high graphitic degree. It is noteworthy that they have exceptionally large surface areas up to 918 m 2 g À1 . The adsorption performance of MPGC are evaluated by using metal ions (Cd 2+ , Cu 2+ , Ag + , Au 3+ ) and dye (Rhodamine B, RhB) in aqueous solutions as the target. The results indicate that MPGC materials exhibit excellent adsorption capacities for metal ions (7.79 mg g À1 for copper for example), which are superior to those of activated carbons and carbon nanotubes. In addition, the materials have also exhibited good ability for adsorption of dye molecular. Notably, MPGC materials could be easily removed for reuse by an external magnet, facilitating separation and reuse of those materials as adsorbents. The adsorption kinetics for these metal ions and dye on MPGC-based adsorbents were well fitted to a pseudo-second order model.

Nitrogen‐Doped Porous Graphitic Carbon as an Excellent Electrode Material for Advanced Supercapacitors

“…Based on the above experimental analysis, it is worth noting that high-temperature treatment could encourage the carbon materials to adopt a graphitic structure, leading to a high crystallinity of the NPGC materials. [18,38] Also, the introduction of melamine increases the amount of graphitic nitrogen (quaternary N species) in the resultant NPGC material, resulting in the formation of high graphitic carbon materials.…”

“…At 900 8C, the carbon source in NPGC-2-900 is completely decomposed and increasing the temperature to 1000 8C can result in the degradation of the carbon skeleton. [18] To research the influence of the nitrogen levels and nitrogen species on the electrode energy-storage characteristics, it is necessary to clarify the content and types of nitrogen species introduced into the carbon materials. These nitrogen species , and N-oxide (N-4) species, respectively.…”

“…[16,17] In general, the improvement of crystallinity can largely enhance the conductivity of carbon materials, but also reduces the surface area dramatically. [18] To improve the capacitive performance of carbon electrode materials, it is important to resolve the conflict between surface area and graphitization. Ruoff et al have demonstrated that porous graphene shows high storage properties.…”

Efficient removal of a typical dye and Cr(vi) reduction using N-doped magnetic porous carbon

“…040850). 16,27,28 Furthermore, compared with N-MPC, the G peak of the MPC is up-shied to 1602 cm À1 , which could also be seen in the CNTs and N-doped CNTs, indicating the successful fabrication of N-doped carbon materials. 25 It can be seen that the intensities of graphite phase become weaker and broader in the order of N-MPC > Ni@GM + KOH > MPC.…”

Magnetically-separable hierarchically porous carbon monoliths with partially graphitized structures as excellent adsorbents for dyes

“…Although some works have been performed in the development of HPCMs [12,13], few attentions have ever been directed towards the synthesis and applications of hierarchically porous carbon monoliths with graphitic structures (HPCM-Gs) [14][15][16]. From the viewpoint of applications, graphitic carbon has some advantages over traditional amorphous carbon, for example, the welldeveloped crystalline structure, intensive interaction of graphitic basic plane with organic dye molecular, good chemical and thermal stability [17][18][19][20][21]. However, until now no fabrication of magnetically-separable HPCM-Gs has been attempted, only few reports regarding carbon powder materials of this type [22,23] In this study, the magnetically-separable hierarchically porous carbon monoliths with partially graphitized structures have been successfully synthesized by using commercial polyurethane (PU) foam as macroporous scaffold associated with a direct carbonization process from triblock copolymer F127, phenolic resol and Fe(NO 3 ) 3 Á9H 2 O.…”