Zhaoqiang Zhang

Ionothermal confined self-organization for hierarchical porous magnesium borate superstructures as highly efficient adsorbents for dye removal

Three-dimensional (3D) hierarchical porous structures self-organized by one-dimensional (1D) building blocks have attracted considerable attention due to their unique properties and versatile applications. Herein, uniform hierarchical porous MgBO2(OH) superstructures with a microsphere-like profile were synthesized for the first time via a facile ionothermal synthesis (150 °C, 12.0 h) using MgCl2, H3BO3 and NaOH as the raw materials, and N,N-dimethylformamide nitrate ionic liquid as the solvent. The porous MgBO2(OH) microspheres exhibited a specific surface area of 57.22 m2 g−1, 82.4% of which had a diameter within the range of 4.0–6.0 μm. The subsequent mild thermal conversion (600 °C, 12.0 h) gave rise to the hierarchical porous Mg2B2O5 microspheres with high crystallinity and a specific surface area of 24.20 m2 g−1. The synergistic effect of the hydrophilic surfaces of the MgBO2(OH) nanostructures and the ionothermally confined self-organization co-contributed to the formation of the hierarchical porous MgBO2(OH) and Mg2B2O5 superstructures, which were employed as adsorbents for Congo red (CR) in simulated waste water. Both MgBO2(OH) and Mg2B2O5 superstructures exhibited good recyclability and reusability as high efficient adsorbents for dye removal after regeneration. The Langmuir isothermal model well interpreted the adsorption behavior of CR. The intra-particle diffusion model was also well fitted based on the kinetic data, indicating microsphere diffusion as the rate-limiting step. The maximum adsorption capacities, qm, for CR onto the porous MgBO2(OH) and Mg2B2O5 superstructures, which were calculated from the Langmuir isothermal model, were 228.3 and 139.3 mg g−1, respectively. The present ionothermally confined self-organization for the hierarchical porous MgBO2(OH) and Mg2B2O5 superstructures provide new insights into the material chemistry, as well as a controllable ionothermal route for hierarchical borate nanoarchitectures. In addition, these superstructures provide a new platform for dye adsorption, and other potential fields, such as heterogeneous catalysis.

Sorting of C4 Olefins with Interpenetrated Hybrid Ultramicroporous Materials by Combining Molecular Recognition and Size-Sieving

C4 olefin separations present one of the great challenges in hydrocarbon purifications owing to their similar structures, thus a single separation mechanism often met with limited success. Herein we report a series of anion-pillared interpenetrated copper coordination for which the cavity and functional site disposition can be varied in 0.2u2005Å scale increments by altering the anion pillars and organic linkers (GeFSIX-2-Cu-i (ZU-32), NbFSIX-2-Cu-i (ZU-52), GeFSIX-14-Cu-i (ZU-33)), which enable selective recognition of different C4 olefins. In these materials the rotation of the organic linkers is controlled to create a contracted flexible pore window that enables the size-exclusion of specific C4 olefins, while still adsorbing significant amounts of 1,3-butadiene (C4 H6 ) or 1-butene (n-C4 H8 ). Combining the molecular recognition and size-sieving effect, these materials unexpectedly realized the sieving of C4 H6 /n-C4 H8 , C4 H6 /iso-C4 H8 , and n-C4 H8 /iso-C4 H8 with high capacity.

Hierarchical Ba2(B5O9)Cl·(H2O)0.5 microspheres: surfactant-assisted facile hydrothermal synthesis, Tb3+ doping and photoluminescence properties

Three-dimensional hierarchical nanoarchitectures of metal borates self-assembled by one-dimensional or two-dimensional nanostructures have been paid extensive attention for their versatile compositions and excellent performance in various fields. Hilgardite-like metal borates have been widely employed as nonlinear optical materials and ideal hosts for various luminescent ions. In this contribution, we reported for the first time a mild surfactant-assisted hydrothermal process for the synthesis of uniform Ba2(B5O9)Cl·(H2O)0.5 microspheres at 160 °C for 6.0 h, by using BaCl2·2H2O, H3BO3, and NaOH as raw materials and ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) as the surfactant. The effects of process parameters and the EDTA-2Na assisted formation mechanism were investigated in detail. The as-obtained microspheres exhibited a transparent characteristic from the ultraviolet to visible range. Within the experimental doping molar percentage of 0–10% in Ba2+, the as-prepared Ba2(B5O9)Cl·(H2O)0.5:6%Tb3+ phosphors demonstrated the strongest PL intensity, revealing the as-obtained Ba2(B5O9)Cl·(H2O)0.5 microspheres as a great promising host candidate for emitting luminescent materials in light display systems or optoelectronic devices.