A hierarchical nanosized pure Si-Beta zeolite was firstly prepared via a micro-zone synchronous crystallization method by steam-assisted conversion taking inorganic silicon sources as raw material. Neither zeolite seeds nor fluoride mineralizing agent was required, only a bit of organic template agent (TEAOH/SiO₂ = 0.05) was sufficient for constructing a self-sustaining plate-like nanosized aggregation with high surface area (631.09 m²/g) and pore volume (0.7 cm³/g) after 24 h period, much less than reported (TEAOH/SiO₂≥0.54, 7–21 d). The pure Si-Beta zeolite also had a superior hydrophobicity than that of hydrothermal synthesis due to the advantage of micro-zone mass transfer. All the properties of resulting samples were investigated by comprehensive characterizations, including X-ray diffraction, scanning and transmission electron microscopy, nitrogen adsorption-desorption, water adsorption, Flourier transform infrared and solid state ²⁹Si nuclear magnetic resonance. Importantly, a “micro-zone synchronous crystallization” mechanism was proposed to explain the formation of mesoporous structure and intrinsic micropores, so as to providing the theoretical guidance for one-step synthesis of hierarchical Beta and other zeolites.

首先通过微区同步结晶法，以无机硅源为原料，通过蒸汽辅助转化法制备了纳米级的纯Si-β分子筛。既不需要沸石种子也不需要氟化矿化剂，仅需少量有机模板剂（TEAOH / SiO ₂  = 0.05）就可以构建具有高表面积（631.09 m ² / g）的自持板状纳米级聚集体，并且24小时后的孔体积（0.7 cm ³ / g），远小于报道的（TEAOH / SiO ₂≥0.54，7–21 d）。由于微区传质的优势，纯Si-Beta沸石也比水热合成具有更好的疏水性。通过综合表征研究了所得样品的所有性能，包括X射线衍射，扫描和透射电子显微镜，氮吸附-脱附，水吸附，Flourier变换红外光谱和固态²⁹ Si核磁共振。重要的是，提出了一种“微区同步结晶”机理来解释介孔结构和固有微孔的形成，从而为逐步合成β-沸石和其他分子筛提供理论指导。