First-principle calculations of sulfur dioxide adsorption on the Ca-montmorillonite.

According to the serious problem of sulfur dioxide pollution, montmorillonite is one of the effective ways in gas pollution control because of its excellent absorption properties. One of the fundamental questions is to fully understand sulfur dioxide absorption mechanism of montmorillonite. In this study, using the first-principle methods, we studied the adsorption characteristics of Ca-montmorillonite in the presence of [Formula: see text]. The adsorption energy and elasticity constants as a function of the adsorption capacity were also studied. The calculated results show that bridge site is the most stable adsorption site for [Formula: see text] with the adsorption energy of - 140 meV. As adsorbent, Ca-montmorillonite is a clay with layer-structure, most of bond lengths(such as Al-O, Mg-O, Si-O, and H-O) does not obviously change. As adsorbed gas, the O-S-O bond angle of adsorbed [Formula: see text] change from [Formula: see text] to [Formula: see text]. The volume and adsorption energies of Ca-montmorillonite almost increase linearly with increasing [Formula: see text] adsorption. By calculating the montmorillonite elasticity constants under different adsorption capacity, we found that the elasticity constant C33 which perpendicular to the crystal face, with the maximum changes from 450 to 326 GPa. In addition, Young's modulus,bulk modulus and shear modulus significantly decrease with the increasing adsorption. The calculated results will not only help to understand the physical and chemical of montmorillonite but may also provide theoretical guidance for dealing with the problem of gas pollution.

Development of novel multifunctional adsorbent by effectively hosting both zwitterionic surfactant and hydrated ferric oxides in montmorillonite.

Intercalating various functional species into the interlayer space is an effective strategy to multi-functionalize 2D materials (e.g., montmorillonite, Mnt), but general limitations have emerged therefrom: (1) various intercalated species compete for the limited interlayer space, and (2) the neighboring intercalated species probably inhibit each other's reactivity. Herein, we have synthesized a novel Mnt-based multifunctional adsorbent (HFO-AZ16Mnt) via intercalation of zwitterionic surfactant (Z16), acid activation by chloric acid, and introduction of hydrated ferric oxides (HFOs). The acid activation can lead to formation of porous nanosilica, which serves as the new active sites for supporting HFO nanoparticles. Employing tetrachloroferrate (FeCl4-) as an anionic precursor of HFOs can help preserve the sulfonyl group (SO3-) of Z16 from being electrostatically occupied during the HFO introduction. As a result, HFO-AZ16Mnt can separately and effectively host Z16 and HFOs. The unique structure endows HFO-AZ16Mnt with the efficiency on simultaneous removal of hydrophobic organic contaminants, oxyanions, and heavy metal cations (nitrobenzene, phosphate, and Cd(II), respectively in this study) from water. Particularly, HFO-AZ16Mnt exhibits impressive capacity towards Cd(II) in both the single- (26.1 mg/g) and the multi-contaminant system (30.6 mg/g). This work has demonstrated a new strategy to multi-functionalize Mnt, and provided a promising novel Mnt-based multifunctional adsorbent for simultaneous and effective removal of organic and inorganic contaminants from water.

Organoclay-derived lamellar silicon carbide/carbon composite as an ideal support for Pt nanoparticles: facile synthesis and toluene oxidation performance.

A lamellar SiC/C composite was synthesized from organoclay via pyrolysis followed by salt-assisted magnesiothermic reduction. The in situ-formed carbon sheet within the restricted interlayer space of clay served as the carbon source and nanotemplate for forming SiC/C. With a large specific surface area, hierarchical porosity, available anchoring sites, good hydrophobicity, and thermal stability, SiC/C proved to be a promising support for Pt. The resulting Pt loaded SiC/C exhibited an excellent toluene oxidation performance.

Correction: In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes.

Correction for 'In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes' by Qingze Chen et al., Chem. Commun., 2019, 55, 2644-2647.

In situ synthesis of a silicon flake/nitrogen-doped graphene-like carbon composite from organoclay for high-performance lithium-ion battery anodes.

A silicon flake/nitrogen-doped graphene-like carbon composite was prepared from organoclay via an in situ strategy, involving carbonization followed by low-temperature aluminothermic reduction. The pre-formed carbon sheets within the confined interlayer space of clay acted as nanotemplates for in situ synthesizing silicon flakes. As a lithium-ion battery anode, the composite exhibited excellent electrochemical properties.