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Placing blocking layers between electrodes has shown paramount prospects in suppressing the shuttle effect of Li–S batteries, but the associated ionic transport would be a concurrent obstacle. Herein, we present a Li-based crystal composited with carbon (LiPN2@C) by a one-step annealing of Li+ absorbed melamine polyphosphate, which simultaneously achieves alleviated polysulfide-shuttling and facilitated Li+ transport. As a homologous crystal, LiPN2 with abundant lithiophilic sites makes Li+ transport more efficient and sustainable. With a LiPN2@C-modified separator, the Li2S cathode exhibits a much-lower activation potential of 2.4 V and a high-rate capacity of 519 mA h g−1 at 2C. Impressively, the battery delivers a capacity of 726 mA h g−1 at 0.5C with a low decay rate of 0.25% per cycle during 100 continuous cycles. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries (PIBs) are attracting increasing attention due to the abundance of K resources, but the sluggish kinetics and inferior cycling stability of anodes still hinder their application. Herein, we present a hybrid 1T/2H phase MoSe2 anode, which shows noticeable pseudocapacitive response and fast kinetics for K storage. Correspondingly, superior electrochemical performances including a high reversible capacity of 440 mA h g−1 after 100 cycles at 0.1 A g−1 and superb rate capacity of 211 mA h g−1 at 20.0 A g−1 are achieved. We believe this work may shed light on the phase engineering of transition metal compounds for rapid charging PIBs. [ABSTRACT FROM AUTHOR]

A versatile low-temperature molten salt approach has been developed for fabricating a MoS2@CoS2 heterostructure electrocatalyst, where low-cost molten KSCN serves as both the reaction medium and sulfur source. The as-obtained electrocatalyst with a defect-rich structure is highly efficient for the hydrogen evolution reaction (HER), delivering a low overpotential of 96 mV at an HER current density of 10 mA cm−2, a small Tafel slope of 60 mV dec−1, and outstanding durability. Density functional theory (DFT) calculations suggest that the heterostructures present an optimized Gibbs free energy of hydrogen adsorption (ΔGH*) close to zero, which is responsible for the excellent HER performance. [ABSTRACT FROM AUTHOR]

Potassium-ion batteries (PIBs) are attracting increasing attention due to the abundance of K resources, but the sluggish kinetics and inferior cycling stability of anodes still hinder their application. Herein, we present a hybrid 1T/2H phase MoSe2 anode, which shows noticeable pseudocapacitive response and fast kinetics for K storage. Correspondingly, superior electrochemical performances including a high reversible capacity of 440 mA h g−1 after 100 cycles at 0.1 A g−1 and superb rate capacity of 211 mA h g−1 at 20.0 A g−1 are achieved. We believe this work may shed light on the phase engineering of transition metal compounds for rapid charging PIBs. [ABSTRACT FROM AUTHOR]