K⁺ intercalated MnO₂ with ultra-long cycling life for high-performance aqueous magnesium-ion hybrid supercapacitors

Abstract

Aqueous magnesium-ion hybrid supercapacitors (MHSs) are very safe, low-cost, and green energy storage systems but confronted with several weaknesses such as low-capacity cathode materials and limited cycling life. In this...

K-birnessite-MnO2/hollow mulberry-like carbon complexes with stabilized and superior rate performance for aqueous magnesium ion storage

“…5g). 43,47,[69][70][71] Moreover, even at a high-power density of 1888.2 W kg −1 , it maintains an energy density of 64.2 W h kg −1 . The cycling stability of MHSs is excellent, showing an outstanding retention of 97.3% after 5000 cycles at 10 A g −1 .…”

“…42 Xu et al fabricated K + intercalated MnO 2 as the aqueous MHS cathode, delivering a maximum energy density of 85.2 W h kg −1 at a power density of 360 W kg −1 and 96.7% capacity retention after 20 000 ultra-long cycles. 43 The studies mentioned above demonstrate that the K + intercalation strategy in manganese oxides can maintain their reversible crystal phase transition during the reaction process and achieve the expansion of the spacing between the layers to enhance the storage of Mg 2+ . 44 However, the improvement of the rate performance is limited due to the structural instability during the reaction, leading to slow kinetics and structural collapse.…”

Hydrogen bond regulating in hydrogel electrolytes for enhancing the antifreeze ability of a flexible zinc-ion hybrid supercapacitor

“…With the rapidly increasing demands of wearable and portable electronic devices, exible electrochemical energy storage systems have attracted growing attention, due to their light weight and excellent exibility. [1][2][3][4][5][6][7] Flexible Zn-ion hybrid supercapacitors (FZHSCs) have become a highly potent energy storage system in the energy storage eld on account of their safety, high capacitance, low maintenance cost and environmental friendliness. [8][9][10] As an emergent polyvalent metal-based hybrid electrochemical device, the FZHSC is regarded as an integration of zinc-based batteries and supercapacitors (SCs).…”

Construction of MnO2–Mn3O4 heterostructures to facilitate high-performance aqueous magnesium ion energy storage

“…In particular, we've compared the performance of MnO 2 –Mn 3 O 4 with other Mn-based materials used in aqueous magnesium ion energy storage and found it to have excellent electrochemical performance and application potential. 8,16–24 Additionally, the MHS exhibits excellent cycling stability, with high capacitance retention of 98.5% even after 5000 cycles at 10 A g −1 . The outstanding properties of MnO 2 –Mn 3 O 4 are attributed to the introduction of the heterostructure, which adds additional pseudo-capacitance.…”