A high-spin Mn-tailored sodium hexacyanoferrate electronic structure enables efficient Mg2+ storage

Abstract

Sodium hexacyanoferrate (NaFeHCF) is a promising cathode material for aqueous magnesium-ion batteries (AMBs) but suffers from limited active site utilization. Here, high-spin Mn is incorporated into the Fe sites of NaFeHCF to modulate its electronic structure, affording NaFe_0.8Mn_0.2HCF. The high-spin Mn efficiently optimizes the electronic structure of NaFeHCF and enhances its storage capacity for Mg²⁺. This work provides insights into the rational design of high-performance electrode materials for AMBs.