biostudies-literatureUnknown13(12)Maiti NWe report a potassium manganese-iron hexacyanoferrate (KMnFeHCF) Prussian blue analog molecular magnet as a promising, low-cost, environmentally friendly cathode for metal-free ammonium-ion aqueous batteries. KMnFeHCF crystallizes in a face-centered cubic structure (Fm3m, lattice constant ≈ 10.19 Å) and exhibits a weak ferromagnetism, with Mössbauer spectroscopy confirming a mixed-valence Fe⁺³/Fe⁺² states. The material delivers a high specific capacity of ~145 mAh/g at 3 A/g, and ~130 mAh/g at 5 A/g along with excellent coulombic efficiency of 97%. Electrochemical performance is governed by reversible Fe²⁺/Fe³⁺ and Mn²⁺/Mn³⁺ redox transitions supported by the open-framework tunnel-like crystal structure which effectively accommodates structural distortions during ammoAdvanced science (Weinheim, Baden-Wurttemberg, Germany)e14287https://www.ebi.ac.uk/biostudies/studies/S-EPMC12948221biostudies-literatureAn Advanced High-Performance Ultrafast Ammonium-Ion Aqueous Battery Based on Dual-Metal Redox Open Framework Molecular Magnet.PMC12948221Mukadam MDMeena SSMaiti NBhatt PSharma MKSamanta SfalseAn Advanced High-Performance Ultrafast Ammonium-Ion Aqueous Battery Based on Dual-Metal Redox Open Framework Molecular Magnet.We report a potassium manganese-iron hexacyanoferrate (KMnFeHCF) Prussian blue analog molecular magnet as a promising, low-cost, environmentally friendly cathode for metal-free ammonium-ion aqueous batteries. KMnFeHCF crystallizes in a face-centered cubic structure (Fm3m, lattice constant ≈ 10.19 Å) and exhibits a weak ferromagnetism, with Mössbauer spectroscopy confirming a mixed-valence Fe⁺³/Fe⁺² states. The material delivers a high specific capacity of ~145 mAh/g at 3 A/g, and ~130 mAh/g at 5 A/g along with excellent coulombic efficiency of 97%. Electrochemical performance is governed by reversible Fe²⁺/Fe³⁺ and Mn²⁺/Mn³⁺ redox transitions supported by the open-framework tunnel-like crystal structure which effectively accommodates structural distortions during ammo2026-01-01T00:00:00Z2026 Feb2026-07-16T22:20:41.451Z2026-07-11T03:12:13.836ZS-EPMC129482214153724210.1002/advs.202514287