Study of The Interaction Carbondioxide Gas with Hydroxyapatite Using Density Functional Theory

Abstract

Hydroxyapatite (HA) is a phosphate mineral with Ca₁₀(PO₄)₆(OH)₂ chemical formula. The hydroxyl group in HA allows ion to exchange, so this material may be applied as a CO₂ gas sensor. The interaction between HA with CO₂ gas is difficult to observe directly, and ab initio modeling is necessarily to investigate the interactions between HA with CO₂ gas. In this study, a simulation was conducted using the density functional theory method to determine the interaction between CO₂ gas on the surface of HA. The simulation results indicate that a large HA surface is required for optimal CO₂ gas adsorption. Pore diameter size needs to be larger than 2.5 Å to prevent binding on two sides of the surface pores.