Pentlandite is the main resource to extract nickel which is a key ingredient for batteries, catalysts, and alloys. Flotation is applied to purify pentlandite from its gangue minerals (i.e., pyrrhotite). However, the adsorption mechanism of flotation collectors with the mixed system is unclear. Herein, first-principles calculations were used to reveal the interfacial bonding mechanisms of xanthate and dixanthogen with pentlandite, pyrrhotite, and their heterostructure. The obtained adsorption configurations and adsorption energy showed that xanthate could interact more strongly with the pentlandite surface due to the strong binding interactions. The adsorption energy and electron localization function showed that the adsorption of collectors on the pentlandite surface had higher priority than pyrrhotite due to the high activity of pentlandite and the existence of galvanic interactions. As verified by the work function results, the heterostructure of pentlandite and pyrrhotite could be seen as a diode where pentlandite played as cathodes permitting the passing of electrons to anode pyrrhotite. This diode model made the selective adsorption of dixanthogen on pentlandite surfaces. This work gives novel research ideas to consider galvanic interactions between the mixed sulfides system. The obtained findings may benefit the development of new purification techniques for pentlandite.

镍黄铁矿是提取镍的主要资源，镍是电池、催化剂和合金的关键成分。浮选用于从脉石矿物（即磁黄铁矿）中提纯镍黄铁矿。然而，混合体系浮选捕收剂的吸附机理尚不清楚。在此，第一性原理计算用于揭示黄药和双黄药与镍黄铁矿、磁黄铁矿及其异质结构的界面结合机制。获得的吸附构型和吸附能表明，由于强结合相互作用，黄药可以与镍黄铁矿表面发生更强烈的相互作用。吸附能和电子局域化函数表明，由于镍黄铁矿的高活性和原电池相互作用的存在，捕收剂在镍黄铁矿表面的吸附优先于磁黄铁矿。正如功函数结果所证实的那样，镍黄铁矿和磁黄铁矿的异质结构可以看作是一个二极管，其中镍黄铁矿充当阴极，允许电子传递到阳极磁黄铁矿。该二极管模型实现了双黄原素在镍黄铁矿表面的选择性吸附。这项工作为考虑混合硫化物系统之间的电偶相互作用提供了新颖的研究思路。获得的发现可能有利于镍黄铁矿新纯化技术的发展。镍黄铁矿和磁黄铁矿的异质结构可以看作是一个二极管，其中镍黄铁矿充当阴极，允许电子传递到阳极磁黄铁矿。该二极管模型实现了双黄原素在镍黄铁矿表面的选择性吸附。这项工作为考虑混合硫化物系统之间的电偶相互作用提供了新颖的研究思路。获得的发现可能有利于镍黄铁矿新纯化技术的发展。镍黄铁矿和磁黄铁矿的异质结构可以看作是一个二极管，其中镍黄铁矿充当阴极，允许电子传递到阳极磁黄铁矿。该二极管模型实现了双黄原素在镍黄铁矿表面的选择性吸附。这项工作为考虑混合硫化物系统之间的电偶相互作用提供了新颖的研究思路。获得的发现可能有利于镍黄铁矿新纯化技术的发展。