tailieunhanh - Báo cáo vật lý: "Influence of the Silica-to-Surfactant Ratio and the pH of Synthesis on the Characteristics of Mesoporous SBA-15"

Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: Influence of the Silica-to-Surfactant Ratio and the pH of Synthesis on the Characteristics of Mesoporous SBA-15 | Journal of Physical Science Vol. 21 2 13-27 2010 13 Influence of the Silica-to-Surfactant Ratio and the pH of Synthesis on the Characteristics of Mesoporous SBA-15 Ahmad Zuhairi Abdullah Noraini Razali and Keat Teong Lee School of Chemical Engineering Universiti Sains Malaysia Engineering Campus Seri Ampangan 14300 USM Nibong Tebal Pulau Pinang Malaysia Corresponding author chzuhairi@ Abstract Mesoporous silica SBA-15 was synthesised with two different sets of synthesis conditions and was characterised using nitrogen adsorption X-ray diffraction XRD transmission electron microscopy TEM and scanning electron microscopy SEM . The effects of the ratio of tetraethylorthosilicate triblockcopolymer TEOS TCP and pH were particularly studied. Well-ordered hexagonal mesoporous silicas were formed at a TEOS TCP ratio of and a pH above 2. The highest surface area and an intense XRD pattern were shown by those synthesised at a ratio of 669 m2 g and cc g . A high TEOS amount disturbed the condensation of the silica network causing failure in the formation of the Si-O-Si network. Keywords mesoporous SBA-15 TEOS TCP ratio pH characteristics Abstrak Silika mesoliang SBA-15 telah dihasilkan melalui dua set keadaan sintesis yang berbeza dan dicirikan menggunakan kaedah penjerapan nitrogen pembelauan sinar X XRD mikroskop elektron transmisi TEM dan mikroskop electron imbasan SEM . Kesan nisbah tetraetilortosilikat kopolimer triblok TEOS TCP dan pH telah dikaji secara khusus. Silika heksagon mesoliang yang teratur telah terbentuk pada nisbah TEOS TCP dan pH melebihi 2. Luas permukaan tertinggi dan pola XRD paling kuat ditunjukkan oleh silica yang disintesis pada nisbah 669 m2 g dan cc g . Amaun TEOS yang terlampau tinggi mengganggu kondensasi jaringan silika menyebabkan kegagalan dalam pembentukan jaringan Si-O-Si. Katakunci mesoliang SBA-15 nisbah TEOS TCP pH ciri-ciri 1. INTRODUCTION The presence of ordered .