Dissolution behavior of NaCaVO4 (111) in aqueous leaching: Experimental and density functional theory study

Sodium calcium vanadate (NaCaVO 4 ), a promising optoelectronic material and key intermediate in vanadium extraction, is crucial for the efficient recovery of vanadium. Combining experimental investigation and density functional theory (DFT) calculations, this study systematically investigates the dissolution mechanism and interfacial interactions of NaCaVO 4 in aqueous media. Experimental findings demonstrate that NaCaVO 4 undergoes hydrolysis during aqueous leaching, preferentially releasing soluble sodium vanadates (NaVO 3 , Na 3 VO 4 ), sparingly soluble calcium vanadates and Ca(OH) 2 precipitates, increasing solution pH. DFT simulations elucidate water molecules dissociate into H + and OH − ions. Bond length and atomic displacement analysis reveal that Na + exhibits a lower migration energy barrier compared to Ca 2+ , explaining selective dissolution and precipitation. This work provides atomic-scale insights into the NaCaVO 4 dissolution, to provide a theoretical reference for optimizing vanadium extraction processes.