title: Insight into morphology and structure of different particle sized kaolinites with same origin.
abstract: The particle size, morphology, crystallinity order and structural defects of four kaolinite samples are characterized by the techniques including particle size analysis, scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR) and magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR). The particle size of four kaolinite samples gradually increases. Four samples all belong to the ordered kaolinite and show a decrease in structural order with the increase of kaolinite particle size. The changes of structural defect are proved by the increase of the band splitting in Raman spectroscopy, the decrease of the intensity of absorption bands in infrared spectroscopy, and the decrease of equivalent silicon atom and the increase of non-equivalent aluminum atom in MAS NMR spectroscopy. The differences in morphology and structural defect are attributed to the broken bonds of Al-O-Si, Al-O-Al and Si-O-Si and the Al substitution for Si in tetrahedral sheets.
authors.affiliation: Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, PR China; School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia. Electronic address: zhangyudehn@hotmail.com.
authors.forename: Yude
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: School of Geoscience and Surveying Engineering, China University of Mining and Technology, Beijing 100083, PR China.
authors.forename: Qinfu
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Cultivating Base for Key Laboratory of Environment-friendly Inorganic Materials in University of Henan Province, School of Materials Science and Engineering, Henan Polytechnic University, Jiaozuo 454000, PR China.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Xiang
authors.affiliation: School of Geoscience and Surveying Engineering, China University of Mining and Technology, Beijing 100083, PR China.
authors.forename: Shilong
authors.initials: S
authors.lastname: Zhang
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia. Electronic address: r.frost@qut.edu.au.
authors.forename: Ray L
authors.initials: RL
authors.lastname: Frost
keywords: Kaolinite; Morphology; Ordered degree; Spectrum; Structural defect