Regulated electrochemical performance of manganese oxide cathode for potassium-ion batteries: A combined experimental and first-principles density functional theory (DFT) investigation

A NiS2/C composite as an innovative anode material for sodium-ion batteries: ex situ XANES and EXAFS studies to investigate the sodium storage mechanism

“…It can be seen that the semicircle diameter becomes larger after cycling NiS 2 /C for 100 cycles, suggesting an increase in the value of R ct . 55 This shows that the conductivity of the composite electrode decreases after cycling it for about 200 cycles, which is attributed to structural deterioration, impeding Na + ion transportation. The rate capability test of the NiS 2 /C composite electrode measured at current densities from 50 mA g −1 to 2000 mA g −1 in the 0.01–3.0 V voltage range as shown in Fig.…”

Theoretical insights into surface-phase transition and ion competition during alkali ion intercalation on the Cu4Se4 nanosheet

“…13 The diffusion barrier of a potassium atom on the neutral Cu 4 Se 4 nanosheet is lower than that on the V 2 Se 2 O monolayer (0.482 eV) 6 and that through the one-dimensional tunnel of the α-MnO 2 electrode (0.31 eV). 34 All these values of migration barriers are adequately low enough to enable very fast ionic diffusion on the surface of the Cu 4 Se 4 nanosheet at room temperature.…”

TheKspgap enabled precipitation transformation reactions from transition metal hydroxides to sulfides for alkali metal ion storage

“…The derived CuS nanostructure was further applied for storing alkali metal ions (Li + , Na + and K + ). [24][25][26][27][28][29] Among them, the SIB exhibits the best rate performance (Fig. 4a).…”