Abstract
Structural and electronic properties of Si termination, O-middle termination, and O-rich terminations of a quartz (001) surface as well as water molecule adsorption on it were simulated by means of density functional theory (DFT). Calculated results show that the O-middle termination exposing a single oxygen atom on the surface is the most stable model of quartz (001) surface, with the lowest surface energy at 1.969 J·m−2, followed by the O-rich termination and Si termination at 2.892 J·m−2 and 2.896 J·m−2, respectively. The surface properties of different terminations mainly depend on the surface-exposed silicon and oxygen atoms, as almost all the contributions to the Fermi level (EF) in density of states (DOS) are offered by the surface-exposed atoms, especially the O2p state. In the molecular adsorption model, H2O prefers to adsorb on the surface Si and O atoms, mainly via O1–H1 bond at 1.259 Å and Si1–Ow at 1.970 Å by Van der Waals force and weak hydrogen bond with an adsorption energy of −57.89 kJ·mol−1. In the dissociative adsorption model, the O-middle termination is hydroxylated after adsorption, generating two new Si–OH silanol groups on the surface and forming the OwH2···O4 hydrogen bond at a length of 2.690 Å, along with a large adsorption energy of −99.37 kJ·mol−1. These variations in the presence of H2O may have a great influence on the subsequent interfacial reactions on the quartz surface.
Highlights
Quartz is an important mineral that has wide applications as a raw material in various fields in industry, such as glass, ceramics, and medicine [1,2,3]
H2O interactions, which has already been identified in studies on thiol collector interaction on galena (PbS) and sphalerite (ZnS) in the presence of water molecules in density functional theory (DFT) [20,33]
DFT calculations were employed to investigate the structural and electronic properties of three distinct terminations of a (001) quartz surface, with subsequent water adsorption studies carried out interactions, which has already been identified in studies on thiol collector interaction on galena (PbS)
Summary
Quartz is an important mineral that has wide applications as a raw material in various fields in industry, such as glass, ceramics, and medicine [1,2,3]. It is the main component mineral of a series of important mineral resources such as siliceous phosphate ore, iron ore, tungsten ore, fluorite, and mica. It is crucial to accurately determine the mineral surface structure so that one can understand its interactions well with other molecules, such as water [6], calcium hydroxyl ions [7], and flotation reagents [5,8,9].
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.