Spontaneous Phase Separation Mediated Synthesis of 3D Mesoporous Carbon with Controllable Cage and Window Size

Abstract

Colloidal silica templated mesoporous carbons, which have not only systematically expanded large cage size (5–45 nm) but also controlled window size (5–25 nm), are successfully obtained via spontaneous phase separation of boron species from mixture of carbon precursor, boric acid, and colloidal silica during carbonization process. This novel synthesis offers a new chance to control the pore structure in materials obtained by nano‐replication using rigid templates.

A combined salt–hard templating approach for synthesis of multi-modal porous carbons used for probing the simultaneous effects of porosity and electrode engineering on EDLC performance

“…Since the carbonization proceeds under solvent free conditions, no further phase segregation appears to take place, enabling the mesopores/macropores generated from silica etching to still retain a relatively sharp peak in their respective pore size distributions. The solution-free carbonization strategy prevents uncontrolled phase segregation of the hydrophilic silica nanoparticles within the carbonizing (and increasingly becoming hydrophobic carbon precursor matrix) and thus alleviates the need for using costly surfactants [58], fast stirring speeds and/or dilute carbon precursor concentrations [59]. In order to confirm this finding, another set of carbonization experiments were performed, where the glucose-colloidal silica-salt solution was directly subjected to carbonization without removing the solvent through the vacuum drying step.…”

Facile Oxygen Reduction on a Three‐Dimensionally Ordered Macroporous Graphitic C3N4/Carbon Composite Electrocatalyst

“…[19,20] Furthermore, the potential prospects of g-C 3 N 4 /C as a substitute for Pt cannot be forecast on the basis of the current research because the ORR catalytic activity of the existing g-C 3 N 4 /C is hardly comparable to Pt [16][17][18] and/or they are not stable enough in the fuel cell environments. [21][22][23][24][25][26][27] Besides, the carbon materials thus synthesized feature uniform cage-like interconnected pores, which not only facilitate the mass transport but also avoid possible confusion in assessing the effect of pore sizes due to structural differences. More specifically, a well-defined and continuous porous structure would facilitate reactant transport inside the pores, assure better contact between catalyst and ionomer, and better stability, as well as create an opportunity for an accurate evaluation of the structural effect of the added carbon on the ORR catalytic properties of g-C 3 N 4 /C.…”

The Effect of Caramelization and Carbonization Temperatures toward Structural Properties of Mesoporous Carbon from Fructose with Zinc Borosilicate Activator

“…Those PSD curves are built based on adsorption data and desorption data because they have correlation with pore cage and pore window, respectively [14]. The PSD curves in Fig.…”

“…In other side, borosilicate is a pore template which physically forms uniformity at 30 nm and 23 nm, but needs enough high carbonization temperature, i.e. 900°C [14].…”

“…In synthesis of carbon from sugar, some researches performed the caramelization before carbonization process at different temperature with different sugar, for example: at 85°C with fructose [11], at 100°C with sucrose [14], and at 100°C with glucose [22]. In transformation of carbohydrate to 5-hydroximethylfurfural (HMF) by acid condition, fructose produce more HMF than sucrose and glucose [23].…”