Lithium Storage Performance Boosted via Delocalizing Charge in Zn Co PS /CoS of 2D/3D Heterostructure.

A promising anode material consisting of bimetallic thiophosphate Zn Co PS and CoS with 2D/3D heterostructure is designed and prepared by an effective chemical transformation. Density functional theory calculations illustrate that the Zn can effectively modulate the electrical ordering of Zn Co PS on the nanoscale: the reduced charge distribution emerging around the Zn ions can enhance the local built-in electric field, which will accelerate the ions migration rate by Coulomb forces and provide tempting opportunities for manipulating Li storage behavior. Moreover, the merits of the large planar size enable Zn Co PS to provide abundant anchoring sites for metallic CoS nanocubes, generating a 2D/3D heterostructure with a strong electric field. The resultant Zn Co PS /CoS can offer the combined advantages of bimetallic alloying and heterostructure in lithium storage applications, leading to outstanding performance as an anode material for lithium-ion batteries. Consequently, a high capacity of 794 mA h g can be retained after 100 cycles at 0.2 A g . Even at 3.0 A g , a satisfactory capacity of 465 mA h g can be delivered. The appealing alloying-heterostructure and electrochemical performance of this bimetallic thiophosphate demonstrate its great promise for applications in practical rechargeable batteries.