Premium
Microwave Effect in the Fast Synthesis of Microporous Materials: Which Stage Between Nucleation and Crystal Growth is Accelerated by Microwave Irradiation?
Author(s) -
Jhung Sung Hwa,
Jin Taihuan,
Hwang Young Kyu,
Chang JongSan
Publication year - 2007
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200700098
Subject(s) - nucleation , microporous material , microwave , materials science , crystal (programming language) , crystal growth , irradiation , crystallography , chemistry , composite material , organic chemistry , physics , quantum mechanics , computer science , nuclear physics , programming language
Microporous materials, such as silicalite‐1 and VSB‐5 molecular sieves, have been synthesized by both microwave irradiation (MW) and conventional electric heating (CE). The accelerated syntheses by microwave irradiation can be quantitatively investigated by various heating modes conducted in two steps such as MW–MW, MW–CE, CE–MW, and CE–CE (in the order of nucleation‐crystal growth). In the case of synthesis by MW–CE or CE–MW, the heating modes were changed for the second step just after the appearance of X‐ray diffraction peaks in the first step. We have quantitatively demonstrated that the microwave irradiation accelerates not only the nucleation but also crystal growth. However, the contribution to decrease the synthesis time by microwave irradiation is larger in the nucleation stage than in the step of crystal growth. The crystal size increases in the order of MW–MW