Bifunctional Cage‐Type Cubic Mesoporous Silica SBA‐1 Nanoparticles for Selective Adsorption of Dyes

Abstract

Bifunctional SBA-1 mesoporous silica nanoparticles (MSNs) with carboxylic acid and amino groups (denoted as CNS-10-10) have been successfully synthesized, characterized, and employed as adsorbents for dye removal. Adsorbent CNS-10-10 shows high affinity towards cationic and anionic dyes in a wide pH range, and exhibits selective dye removal of a two-dye mixture system of cationic methylene blue and anionic eosin Y. By changing the pH of the medium, the selectivity of the adsorption behavior can be easily modulated. For comparison purposes, the counterparts, that is, pure silica SBA-1 MSNs (CS-0) and those with either carboxylic acid or amino functional groups (denoted as CS-10 and NS-10, respectively) were also prepared to evaluate their dye-adsorption behaviors. As revealed by the zeta-potential measurements, the electrostatic interaction between the adsorbent surface and the dye molecule plays an important role in the adsorption mechanism. Adsorbent CNS-10-10 can be easily regenerated and reused, and maintains its adsorption efficiency up to 80 % after four cycles.

Synthesis, Characterization and Use of Mesoporous Silicas of the Following Types SBA-1, SBA-2, HMM-1 and HMM-2

“…Mesoporous silica materials, characterized by a well-developed porous structure and specific surface area, as well as the possibility to modify their surface using organic functional groups, show great potential for use as adsorbents for dyes. Therefore, Lin et al [ 77 ] have synthesized bifunctional mesoporous SBA-1 silicas, modified with carboxylic and amino groups, in order to apply them for adsorption of toxic anionic or cationic dyes. They used PAA/CPC complex as a template and TEOS as a silicon precursor and performed the synthesis in basic conditions.…”

“…The SBA-1 silicas modified with amino groups exhibited strong ability to adsorb anionic dyes at low pH, because of the interactions of –NH 3 + groups with anionic dyes. Particularly promising for selective removal of a given dye from a mixture of cationic and anionic dyes proved to be SBA-1 modified with both carboxyl and amino groups [ 77 ].…”

Recent Advances in Facile Liquid Phase Epoxidation of Light Olefins over Heterogeneous Molybdenum Catalysts

“…In 1998, Stucky and group synthesized a type of hexagonal array of pores SBA materials. [74] A wide variety of SBA materials have been reported in the literature such as SBA-1/ SBA-6 (Pm3n, cubic), [75] SBA-2/SBA-12 (P63/mmc), [76] SBA-8 (C2 mm), SBA-11 (Pm3 m), [77] SBA-15 (P6 mm, hexagonal), [74] and SBA-16 (Im3 m, cubic). [78] Among them, Figure 7.…”

Molecular recognition of catechols on the crystal-like surface of periodic mesoporous organosilica containing pyridinylethynylpyridine

“…[17][18][19][20] Since the discovery of mesoporous silica, much attention has been given on its adsorption properties for application as an adsorbent for heavy metals, hazardous substances, organic dyes, and biomolecules. [21][22][23][24][25][26][27][28][29][30] Additionally, mesoporous silica materials have a great advantage of a controllable pore structure with a high surface area as an adsorption site and biocompatibility for biomedical applications. Recently, much effort has been devoted to applying them for drug delivery systems and bioimaging.…”