Boosting potassium storage performance via construction of NbSe2–based misfit layered chalcogenides

Dual Regulation of Metal Doping and Adjusting Cut‐Off Voltage for MoSe2 to Achieve Reversible Sodium Storage

“…2D transition metal selenides, as a promising anode candidate for SIBs, have received enormous concern on account of prominent superiority in aspect of unique layered structure and favorable physicochemical properties. [20][21][22] Specifically, the smaller thickness and larger ratio of surface to volume for 2D transition metal selenides endow them with more ample active sites, lower intercalation barriers, and shorter diffusion distance for metal-ions than the bulk counterparts, especially for accommodating Na + with larger ionic radius and eventually, contributing to sufficient electrochemical reactions, high capacity as well as accelerated reaction kinetics. [23,24] Up to now, several kinds of 2D transition metal selenides have been successfully prepared and employed in storing Na-ions, such as MoSe 2 , WSe 2 , VSe 2 , and Nb 2 Se 9 .…”

Bulk Superlattice Analogues for Energy Conversion

“…With their adaptability for alkali intercalation, misfit compounds are preferable for the performance of KIBs. For example, very recently Peng et al first introduced a misfit superlattice as an anode material in KIBs and obtained a capacity of ∼300 mA h g –1 at 0.1 A g –1 after 300 cycles in exfoliated (SnSe) 1.16 NbSe 2 and (PbSe) 1.14 NbSe 2 with a thickness of 4–5 nm …”

“…16 NbSe 2 and (PbSe) 1.14 NbSe 2 with a thickness of 4−5 nm. 19 For layered materials, the diffusion rate of Li ions in electrodes with a thickness of micrometers is the limiting factor of battery performance in comparison to the charge-transfer reaction. 20,21 When the thickness is reduced to ∼10 nm, the structural instability induced by intercalation and deintercalation of alkali ions becomes intense and leads to novel physical phenomena such as a local phase transition from 2H to 1T′ in MoS 2 22 and a charge density wave (superlattice reconfiguration) in 2H-TaS 2 .…”

A novel strategy for encapsulating metal sulfide nanoparticles inside hollow carbon nanosphere-aggregated microspheres for efficient potassium ion storage

“…1,2 Lithium-ion batteries (LIBs) are widely used in these elds because of their high energy density and long cycle life. [3][4][5][6] However, LIBs are at a disadvantage in meeting the increasing demand owing to their high price, uneven geological distribution, and shortage of Li resources. 7,8 Potassium-ion batteries (PIBs) are considered promising alternatives to LIBs because of their abundant reserves, the relatively low price of potassium resources, and their similar standard redox potential.…”

“…(2) The well-dened carbon framework provides structural integrity and facilitates efficient electron transfer in a 3D interconnected network. (3) The void space between the yolk and the shell, and the carbon shell effectively accommodates the volume variation during potassium ion ingress/egress. (4) Porous shells of hollow carbon nanospheres enable easy penetration of the electrolyte.…”