MnAl Layered Double Hydroxides: A Robust Host for Aqueous Ammonium‐Ion Storage with Stable Plateau and High Capacity

Abstract

Rechargeable aqueous batteries based on ammonium‐ions shows great potential in low‐cost energy storage systems owing to their prominent superior characteristics, including ultrafast kinetics, long‐term lifespan, and environmental friendliness. Nevertheless, their development is severely challenged by the fact that the as‐reported cathode materials generally fail to satisfy the requirements on high capacity and stable working voltage simultaneously. Herein, the first NH4+ storage behavior in a MnAl layered double hydroxide (LDH) series is reported. Intriguingly, stable working voltage at 0.2 V is observed in the optimized Mn3Al1‐LDH sample with a high discharge capacity of 183.7 mAh g−1 at 0.1 A g−1. When assembling the rocking‐chair battery using a 3,4,9,10‐perylenetetracarboxylic diimide anode, the full battery delivers a high energy density of 45.8 Wh kg−1, surpassing most of its recently reported counterparts. A rapid amorphization conversion of the LDH cathode during the first charge process is revealed, which should be beneficial to NH4+ isotropic transport accompanied by a highly reversible building/breaking process of hydrogen bonds. The results realize a novel layered inorganic cathode material with superior performance for aqueous ammonium‐ion batteries, and the amorphization conversion to facilitate ion storage provides new insight into electrode design for aqueous batteries.

Quantitative Regulation of Interlayer Space of NH4V4O10 for Fast and Durable Zn2+ and NH4+ Storage

“…[39][40][41][42][43][44][45] and multiple redox reactions of vanadium (Figure 5e; and Table S2, Supporting Information). [39][40][41][42][43][44][45] Additionally, at high applied current density of 5 A g −1 , NH 4 V 4 O 10 can deliver a specific capacity of 90 mA h g −1 which recovers to 230 mA h g −1 when the current density goes back to 0.2 A g −1 , demonstrating a superior rate capability in aqueous NH 4 + storage (Figure 5b). The cycle performance of NH 4 V 4 O 10 was also recorded at current density of 1 A g −1 (Figure 5c).…”

“…d) Long cycle performance at 5 A g −1 . e) Comparison of NH 4 V 4 O 10 versus state-of-the-art materials for NH 4+ storage in the current density of 0.1 A g −1 [39][40][41][42][43][44][45].…”

Construction of the Porous Carbon Supercapacitors with Efficient Energy Storage by the Dissolution and Regeneration Strategy of Chitin

“…The existence of nitrogen- and oxygen-containing functional groups could effectively improve PCMs’ stability and electron-transfer performance. It could improve the wettability of PCMs and provide pseudocapacitance. ,– Therefore, the presence of these heteroatoms provided a basis for effectively improving the performance of PCMs in electrochemical behavior.…”

Redox mediator-enhanced charge storage in dimensionally tailored nanostructures towards flexible hybrid solid-state supercapacitors

“…As per the charge storage mechanism, electrochemical capacitors have been classied as electrical doublelayer capacitors (EDLCs), which arise from ion adsorption, and pseudo capacitors, which originate from surface faradaic redox reactions. [1][2][3][4][5][6] As conventional carbon-based electrode materials have approached the theoretical capacity limits, carbon-free alternatives with ultra-high capacitance are urgently required. 7,8 Alternatively, transition metal oxides, with their high charge storage capacities based on the conversion reaction mechanism as well as their abundance, have been extensively utilized.…”

“…As per the charge storage mechanism, electrochemical capacitors have been classified as electrical double-layer capacitors (EDLCs), which arise from ion adsorption, and pseudo capacitors, which originate from surface faradaic redox reactions. 1–6 As conventional carbon-based electrode materials have approached the theoretical capacity limits, carbon-free alternatives with ultra-high capacitance are urgently required. 7,8…”