Abstract: In order to explore the surface wetting characteristics of bismuthinite，aiming at the prob⁃ lem that the theoretical research on the surface anisotropy of bismuthinite is still vacant，the adsorption be⁃ havior of single water molecule，monolayer water molecule and multi-layer water molecule on different crystal surfaces of bismuthinite is systematically studied from the atomic scale by using the simulation cal⁃ culation based on density functional theory，and the differences of different crystal surfaces are discussed by adsorption energy and density of states.The results show that the adsorption energy of a single water mol⁃ ecule adsorbed on the（100）and（120）surfaces of bismuthinite is -103.66 kJ/mol and -94.85 kJ/mol， respectively，which is a hydrophobic“surface”. The adsorption energy of a single water molecule on the （010）surface is 14.9 kJ/mol，which is a hydrophilic“edge”.The monolayer water molecules on the（010） surface are mainly hydrogen bonding and no obvious adsorption is formed. On the（100）and（120）surfac⁃ es，water molecules are adsorbed on the exposed Bi atoms，and interact in the form of hydrogen bonds at the exposed S sites.When multilayer water molecules are on the（010）surface，the hydrogen bonds be⁃ tween water molecules in the z direction weaken their interaction with the surface，while the average bond length of the adsorption bond on the（100）and（120）surfaces is shortened，indicating that the adsorption of multilayer water molecules on the hydrophilic surface is stronger.This study reveals the difference in hy⁃ drophilicity and hydrophobicity of different crystal planes of bismuthinite，which can provide a theoretical supplement for its efficient flotation recovery.

Key words: bismuthinite, density functional theory, anisotropy, water adsorption