Preinserted Ammonium in MnO<sub>2</sub> to Enhance Charge Storage in Dimethyl Sulfoxide Based Zinc-Ion Batteries
Wathanyu Kao‐ian, Jinnawat Sangsawang, Mohan Gopalakrishnan, Suttipong Wannapaiboon, Athis Watwiangkham, Siriporn Jungsuttiwong, Jayaraman Theerthagiri, Myong Yong Choi, Soorathep Kheawhom
Abstract
High Resolution Image Download MS PowerPoint Slide Nonaqueous zinc-ion batteries (NZIBs) featuring manganese dioxide (MnO 2 ) cathodes position themselves as viable options for large-scale energy storage systems. Herein, we demonstrate the use of ammonium cation as a preintercalant to improve the performance of the δ-MnO 2 cathode in wet dimethyl sulfoxide based electrolytes. Employing in situ X-ray absorption spectroscopy, Raman spectroscopy, and synchrotron X-ray diffraction, we reveal that the integration of ammonium cations promotes the formation of NH–O–Mn networks. These networks are crucial for manipulating the distortion of the MnO 6 octahedral units during discharging, thereby mitigating charge disproportionation, which is a primary limitation to MnO 2 ’s charge-storage efficiency. The modified MnO 2, through this idea, displays a notable improvement in capacity (∼247 mAh/g) and can pass charge–discharge cycles up to 500 cycles with a capacity retention of 85%. These findings underscore the potential of modified MnO 2 in advancing MnO 2 -based hosts for Zn-MnO 2 batteries, marking significant progress toward next-generation energy storage solutions.