Abstract
The past two decades have been marked by an increased interest in the synthesis and the properties of geoinspired hydrosilicate nanoscrolls and nanotubes. The present review considers three main representatives of this group: halloysite, imogolite and chrysotile. These hydrosilicates have the ability of spontaneous curling (scrolling) due to a number of crystal structure features, including the size and chemical composition differences between the sheets, (or the void in the gibbsite sheet and SiO2 tetrahedron, in the case of imogolite). Mineral nanoscrolls and nanotubes consist of the most abundant elements, like magnesium, aluminium and silicon, accompanied by uncontrollable amounts of impurities (other elements and phases), which hinder their high technology applications. The development of a synthetic approach makes it possible to not only to overcome the purity issues, but also to enhance the chemical composition of the nanotubular particles by controllable cation doping. The first part of the review covers some principles of the cation doping approach and proposes joint criteria for the semiquantitative prediction of morphological changes that occur. The second part focuses on some doping-related properties and applications, such as morphological control, uptake and release, magnetic and mechanical properties, and catalysis.
Highlights
The year 2020 can be considered as the 90th anniversary of inorganic nanotubes
The modelling modelling of of hydrosilicate hydrosilicate nanotubes nanotubes enables a study of their morphology and of their mechanical and electronic properties
The lack of pure halloysite nanotubes synthesis reports suggests some hindrances; if these could be overcome, this should open a path for the synthesis of a number of halloysite-type scrolling
Summary
The year 2020 can be considered as the 90th anniversary of inorganic nanotubes. In 1930, L. Revealing imogolite’s tubular morphology was more challenging than with chrysotile and halloysite because of the substantially smaller size of the former Despite such a long history of the study of tubular hydrosilicate particles, the famous term ‘nanotube’. A general aim of cation doping is to confer a new property on the hydrosilicate nanotube, so this should be discussed as well In accordance with these aims, the present review consists of three sections, in addition to the Introduction and Conclusion. We will use both the term ‘nanotube’ and ‘nanoscroll’, because both forms of cross-section can be observed for hydrosilicates. ‘Nanoscroll’ is more appropriate when a is model based on a spiral form, or when a formation mechanism via scrolling, is considered
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.