Semi-coherent cation-rich Mn-Cu oxides heterostructures as cathode for novel aqueous potassium dual-ion energy storage devices

Linfeng Jiang; Chenglong Shi; Youyong Pang; Yongping Liu; Jinliang Li; Wenjie Mai; Bo-Tian Liu

doi:10.1016/j.jcis.2021.03.182

Semi-coherent cation-rich Mn-Cu oxides heterostructures as cathode for novel aqueous potassium dual-ion energy storage devices

J Colloid Interface Sci. 2021 Sep:597:75-83. doi: 10.1016/j.jcis.2021.03.182. Epub 2021 Apr 5.

Authors

Linfeng Jiang¹, Chenglong Shi¹, Youyong Pang¹, Yongping Liu¹, Jinliang Li², Wenjie Mai³, Bo-Tian Liu⁴

Affiliations

¹ Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials, Department of Chemistry and Biological Engineering, Guilin University of Technology, Guilin 541004, China.
² Siyuan Laboratory, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Materials, Department of Physics, Jinan University, Guangzhou 510632, China.
³ Siyuan Laboratory, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Materials, Department of Physics, Jinan University, Guangzhou 510632, China. Electronic address: wenjiemai@email.jnu.edu.cn.
⁴ Guangxi Key Laboratory of Electrochemical and Magneto-chemical Functional Materials, Department of Chemistry and Biological Engineering, Guilin University of Technology, Guilin 541004, China; Guangdong Institute of Semiconductor Industrial Technology, Guangdong Academy of Science, Guangzhou 510650, China; Siyuan Laboratory, Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Materials, Department of Physics, Jinan University, Guangzhou 510632, China. Electronic address: btliu2018@glut.edu.cn.

PMID: 33862448
DOI: 10.1016/j.jcis.2021.03.182

Abstract

In this work, combining both advantages of aqueous energy storage systems (ESS) and conventional dual-ion ESS, a novel aqueous dual-ion ESS is developed based on K⁺ and OH^- electrochemistry by employing semi-coherent K_1.33Mn₈O₁₆-CuO (sc-Mn-Cu) cathode. Profting from the elaborate design, the electrolyte and cathode simultaneously act as source of cations. In the novel aqueous dual-ion ESS configuration, the dependence of the performance on the electrolyte salt concentration is reduced and the sc-Mn-Cu cathode can host OH^- with lower working potentials by conversion mechanism. Furthermore, based on the sc-Mn-Cu cathode and freestanding V₂O₃-VC (fs-V₂O₃-VC) anode, we developed a flexible quasi-solid-state device. Remarkably, it exhibits an ultrahigh energy density of ~39.9 μW h cm^-2 together with high power density of carbon-based devices, which outperforms most previously reported flexible storage devices to our knowledge. These results indicating that the unique mechanism of the sc-Mn-Cu cathode opens up a promising direction for low-cost and high-performance novel aqueous ESS.

Keywords: Aqueous K-ion batteries; Dual-ion storage; Flexible energy storage devices; Ultra-stable cathode; Ultrahigh areal capacity.