Superior Potassium Ion Storage via Vertical MoS₂ “Nano‐Rose” with Expanded Interlayers on Graphene

Abstract

Potassium has its unique advantages over lithium or sodium as a charge carrier in rechargeable batteries. However, progresses in K-ion battery (KIB) chemistry have so far been hindered by lacking suitable electrode materials to host the relatively large K ions compared to its Li and Na counterparts. Herein, molybdenum disulfide (MoS ) "roses" grown on reduced graphene oxide sheets (MoS @rGO) are synthesized via a two-step solvothermal route. The as-synthesized MoS @rGO composite, with expanded interlayer spacing of MoS , chemically bonded between MoS and rGO, and a unique nano-architecture, displays the one of the best electrochemical performances to date as an anode material for nonaqueous KIBs. More importantly, a combined K storage mechanism of intercalation and conversion reaction is also revealed. The findings presented indicate the enormous potential of layered metal dichalcogenides as advanced electrode materials for high-performance KIBs and also provide new insights and understanding of K storage mechanism.

Rhenium Diselenide Anchored on Reduced Graphene Oxide as Anode with Cyclic Stability for Potassium‐Ion Battery

“…It could be attributed to the oxidation of ReSe 2 , suggesting 80% loss of ReSe 2 in the ReSe 2 @rGO sample. The further weight loss of about 20.2% at 400–580 °C was probably due to the oxidation of rGO, which was close to the EDS result (Figure f) showing that the mass ratio of C in the sample was about 28% …”

A Robust Solid Electrolyte Interphase Layer Augments the Ion Storage Capacity of Bimetallic‐Sulfide‐Containing Potassium‐Ion Batteries

“…[18] Liu et al constructed thinly layered antimony sulfide/carbon sheet composites by solution-triggered one-step shear exfoliation, to produce an electrode with ah igh potassium-ion storage capacity (404 mAh g À1 at 500 mA g À1 after 200 cycles). [20] Zhao et al synthesized yolk-shell FeS 2 @C structure composites by awet-chemical method with thermal treatment;the material maintained acapacity of 270 mAh g À1 at 300 mA g À1 after 1000 cycles. [20] Zhao et al synthesized yolk-shell FeS 2 @C structure composites by awet-chemical method with thermal treatment;the material maintained acapacity of 270 mAh g À1 at 300 mA g À1 after 1000 cycles.…”

A Dual Carbon‐Based Potassium Dual Ion Battery with Robust Comprehensive Performance

“…However, the relatively limited reserve and uneven geographical distribution of the lithium resources give a tremendous challenge to LIBs for meeting the continuously increasing requirement on the high performance‐to‐cost ratios. Therefore, other metal ion batteries such as sodium (Na) ion batteries (SIBs), potassium (K) ion batteries (PIBs), and aluminum ion batteries have gained notable attention. Moreover, SIBs and PIBs are of particular interest because of the similar physicochemical properties to Li, and relatively high abundance, low cost, and geographically uniform distribution of Na and K. Meanwhile, it is noteworthy that the standard electrode potential of K/K + (−2.93 V vs SHE) is lower than that of Na/Na + (−2.71 V vs SHE), indicating a higher working voltage for PIBs.…”