Understanding the anisotropic wettability of spodumene from direct force measurement using AFM and density functional theory calculations.

• Wettability differences of spodumene anisotropic crystal surfaces are investigated. • Contact angle relaxation, AFM, and DFT calculations are performed. • Explained differences in the wettability of spodumene anisotropic crystal planes. • Types and number of fracture bonds per unit area are the main influencing factors. • Wettability of water molecules on crystal planes is simulated via DFT calculations. Wettability directly reflects the interaction between minerals, reagents, and water, and is a key factor determining the flotation separation of minerals. Wettability differences of the spodumene anisotropic crystal surfaces are investigated in this study using contact angle relaxation, atomic force microscopy (AFM), and density functional theory (DFT) calculations. The contact angle relaxation and AFM tests confirm the anisotropic wettability of spodumene surfaces from macro and micro perspectives, respectively, and the order of hydrophilicity is (0 1 0) > (1 0 0) > (1 1 0). The DFT calculations based on surface fracture key points and broken bond density explain the differences in the wettability of spodumene crystal surfaces, that is, the types of broken bonds and the number of broken bonds per unit area are the main influencing factors. The wettability of water molecules on different crystal surfaces is simulated based on the DFT calculations of the broken surface bonds and surface energy, which further verifies the experimental results. [ABSTRACT FROM AUTHOR]