Mg-Al mixed oxides with highly accessible basic sites were synthesized from Mg-Al layered double hydroxides bearing interlayer isethionates (Ise). Anion-exchange of interlayer carbonates in synthetic hydrotalcites with Ise induces stacking disorders in layered structure, and subsequent delamination in water followed by drying causes further disordering as characterized by X-ray diffraction technique. However, thermal activation of these materials in air formed Mg-Al mixed oxides with low surface area and low CO₂ adsorption capacity. In contrast, thermal activation in N₂ or N₂ followed by air formed materials exhibiting marked increases in CO₂ adsorption capacity up to ∼800% relative to those obtained by thermal activation in air. Thermogravimetric and elemental analyses and IR spectroscopy characterization indicate that thermal activation in N₂ enables removal of sulfur species formed from Ise at ∼400 °C, and limits the formation of sulfate species that bridge nanosheets and cause irreversible stacking of them. The proper thermal activation procedure in addition to disordered structure of aggregates of Mg-Al double hydroxide nanosheets enabled the formation of Mg-Al mixed oxides with higher surface area and larger micropore volume than those obtained from the initial hydrotalcites. These results highlight the critical importance of thermal activation steps for such materials, and demonstrate a prospective route to synthesize new porous materials based on Mg-Al mixed oxides.

由具有层间乙磺酸盐（Ise）的Mg-Al层状双氢氧化物合成了具有高度可及的碱性位点的Mg-Al混合氧化物。用Ise交换合成水滑石中层间碳酸盐的阴离子，会引起层状结构的堆垛紊乱，随后在水中分层并随后干燥会导致进一步的紊乱，如X射线衍射技术所表征。然而，这些材料在空气中的热活化形成具有低表面积和低CO ₂吸附能力的Mg-Al混合氧化物。相反，在N ₂或N _2中进行热活化，然后在空气中形成的材料中CO ₂显着增加相对于在空气中热活化所获得的吸附能力，其吸附能力高达〜800％。热重和元素分析以及红外光谱表征表明N _2中的热活化能够去除约400°C时从伊势形成的硫物种，并限制了桥接纳米片并导致不可逆堆积的硫酸盐物种的形成。Mg-Al双氢氧化物纳米片聚集体的无序结构以及适当的热活化程序使得形成的Mg-Al混合氧化物比从初始水滑石中获得的表面积和微孔体积更大。这些结果突出了热活化步骤对此类材料的至关重要性，并证明了合成基于Mg-Al混合氧化物的新型多孔材料的前瞻性途径。