Fabrication of attapulgite/C3N4 hybridized metal organic framework nanocomposites by different strategies and study on adsorption properties for alizarin yellow GG

Recent developments in synthesis of attapulgite composite materials for refractory organic wastewater treatment: a review

“…The possible adsorption mechanisms of the refractory organics by attapulgite-based absorbents are based on the following properties: (i) the micropores, mesopores, and macropores structure of ATP or ATP-based composites, which facilitates the free diffusion of pollutants and guarantees mass transport to the internal structure; (ii) aer introduction of organics to ATP, [74][75][76][77][78][79] the surface functional groups, surface structure and the hydrophobicity of ATP had been changed, fully increased the exposed active sites (-NH 3 , oxygen-containing groups etc.) and negative charges, which made it favorable for encountering and capturing cationic molecules via hydrogen bonds and electrostatic interaction; 81 (iii) combined ATP with carbon series materials (GO, g-C 3 N 4 ) [95][96][97][98][99][100][101][102][103][104][105][106] or Fe series materials (nZVI) [107][108][109] to enhance specic surface area and conductivity, and these substances on ATP maybe have chemical reactions with the adsorbates, 107,109 reach the goal of refractory organics removal; (iv) the crystalline water in the structure of attapulgite is located on the surface of its channel, which is easy to form hydrogen bonds with the adsorbate entering the channel; [95][96][97] (v) some ATP based catalysts (such as APT/C@NiFe-LDHs 96 ) with primarily p-p stacking could act as electron acceptors and be conducive to adsorbing the cationic pollutants with unsaturated double bond or conjugate structure, and cation-p bonding 95 can be formed between cation and prich electronic structure by electrostatic attraction and polarization. All these above examples reveal that p-p interaction, hydrophobic effect, cation-p bonding, chemical complexation, hydrogen bond and electrostatic attraction are mainly involved in the adsorption process.…”

“…As a new non-metallic photocatalytic material, g-C 3 N 4 has a wider absorption spectrum range and does not require ultraviolet light, it can play a photocatalytic role under ordinary visible light. 104,105 Liu et al 106 synthesized attapulgite (APT) and C 3 N 4 hybridized metal–organic frameworks (MOFs) via different strategies, and systematically studied its adsorption properties for alizarin yellow GG (AYGG). The result showed that APT/C 3 N 4 had excellent adsorption capacity synthesized both by refluxing method (366.0 mg g −1 ) and by hydrothermal method (271.8 mg g −1 ).…”