Hierarchical Porous Carbon Embedded MoSe2 Effectively Improve Cycle Stability in K‐Se Battery

Abstract It is a crucial challenge to control the dissolution and diffusion of polyselenides in the K−Se system. Herein, a polar material MoSe 2 was introduced into Chitosan‐derived hierarchical porous carbon (MoSe 2 ‐HPC) for the first time by a simple freeze‐dried carbonization method, which was used as host materials of Se. The porous carbon plays a vital role in alleviating volume expansion from Se to K 2 Se and affording physical restriction effect for generating potassium polyselenides (KPSs). The adsorption experiment can prove that the additive MoSe 2 as active site can effectively anchor soluble KPSs by remarkable polar interaction to achieve raising electrochemistry performance. Therefore, the Se@MoSe 2 ‐HPC cathode presents superior cycling stability with a specific capacity of 323.2 mAh g −1 after 500 cycles at 1 C and satisfactory rate performance of 261.7 mAh g −1 at 5 C, demonstrating the great potential of MoSe 2 as polar adsorption component for K−Se batteries cathode materials.