Abstract
Wollastonite (CaSiO3) is an important mineral that is widely used in ceramics and polymer industries. Defect energetics, diffusion of Ca ions and a solution of dopants are studied using atomistic-scale simulation based on the classical pair potentials. The energetically favourable defect process is calculated to be the Ca-Si anti-site defect cluster in which both Ca and Si swap their atomic positions simultaneously. It is calculated that the Ca ion migrates in the ab plane with an activation energy of 1.59 eV, inferring its slow diffusion. Favourable isovalent dopants on the Ca and Si sites are Sr2+ and Ge4+, respectively. Subvalent doping by Al on the Si site is a favourable process to incorporate additional Ca in the form of interstitials in CaSiO3. This engineering strategy would increase the capacity of this material.
Highlights
Wollastonite is an important naturally occurring or synthetic mineral of great interest in the development of ceramics, plastics and paints [1,2,3,4]
Though wollastonite is mined from ores for large-scale commercial applications, there are many experimental reports explaining the procedures of synthesising and characterising wollastonite in laboratories [1,5,10,13,14]
Abd Rashid et al [1] used the solid-state reaction method at low temperature to produce wollastonite from limestone and silica sand and concluded that the resultant compound is expected to exhibit good physical properties due to the experimental density that is close to its theoretical value
Summary
Wollastonite is an important naturally occurring or synthetic mineral of great interest in the development of ceramics, plastics and paints [1,2,3,4]. This mineral is mainly found in the USA, India, Mexico, China, Turkey and Finland [5]. Edrees et al [20] used density functional theory (DFT) simulations to analyse the structural, mechanical, optical and electronic properties of wollastonite. There are no experimental or theoretical studies on intrinsic defects, diffusion or dopants of wollastonite in the literature. The presence of defects in a material is important, as they influence its physical, mechanical and optical properties
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
