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Although Li-rich layered materials are some of the best potential cathode materials owing to their high capacity (>250 mA h g−1), low cost and reduced pollution, they still faces some problems, including low initial coulombic efficiency, poor cycling performance, and bad rate capability. In this work, Li-rich spinel Li4Mn5O12 and MgF2 are constructed on the surface of a Li-rich layered material by simple liquid-phase erosion and liquid-phase deposition methods, respectively. The Li-rich spinel Li4Mn5O12 layer provides 3D Li-ion channels and it restrains the growth of SEI film and oxygen release. The outermost amorphous MgF2 layer of coating also favors Li-ion migration and further protects Li4Mn5O12 from HF corrosion. It is found that the double surface modifications induce a phase transformation from a layered structure to an Li4Mn5O12-type spinel during cycling, which is different from the traditional structural transformation from a layered structure to a LiMn2O4 spinel-like structure, and it exhibits a slower structural transformation. Benefiting from these collaborative contributions from Li4Mn5O12 and MgF2, the material shows superior electrochemical properties, including a high initial coulombic efficiency of 96.4%, excellent capacity retention of 80% after 300 cycles, a small voltage decay rate of 1.5 mV per cycle, and a remarkable rate capability. [ABSTRACT FROM AUTHOR]

While Li‐rich layered materials are one of the most promising next‐generation cathode materials for Li‐ion batteries, they still face some challenges, such as large irreversible capacity, bad cycling performance, and inferior rate capability. In this work, MnF2 nanolayers are successfully coated on Li1.2Ni0.2Mn0.6O2 (LNMO) samples. There is a great progress in the electrochemical performance of LNMO after coating MnF2 nanolayers. The pristine LNMO shows a discharge capacity of only 269.4 mAhg−1, and after coating, MF‐1.5 (coating weight percent of 1.5%) the sample exhibits a high initial discharge capacity of 296.8 mAhg−1. Furthermore, the MF‐2.5 sample displays improved capacity retention of 85% after 100 cycles at 0.5 C. In terms of rate capability, MF‐1.5 retains 141.7 mAhg−1 of capacity at 5 C compared with pristine LNMO, which is only 70.4 mAhg−1. The enhanced electrochemical performance of MnF2‐coated samples is attributed to the conversion reaction of the MnF2 layer, which limits the electrode–electrolyte side reaction and decreases the dissolution of transition metal ions in the electrolyte. In addition, there is spinel phase formation after coating the MnF2 nanolayer, which promotes Li‐ion transfer and further restrains the transformation of structure on the surface of the material. [ABSTRACT FROM AUTHOR]

It is facing a tremendous challenge to develop the desirable hybrids for photocatalytic H 2 generation by integrating the advantages of a single semiconductor. Herein, an all-sulfide ZnIn 2 S 4 /CdS/PdS heterojunction is constructed for the first time, where CdS and PdS nanoparticles anchor in the spaces of ZnIn 2 S 4 micro-flowers due to the confinement effects. The morphology engineering can guarantee rapid charge transfer owing to the short carrier migration distances and the luxuriant reactive sites provided by ZnIn 2 S 4 . The S-scheme mechanism between ZnIn 2 S 4 and CdS assisted by PdS cocatalyst is testified by in situ irradiated X-ray photoelectron spectroscopy and electron paramagnetic resonance (EPR), where the electrons and holes move in reverse driven by work function difference and built-in electric field at the interfaces. The optimal ZnIn 2 S 4 /CdS/PdS performs a glaring photocatalytic activity of 191.9 µmol h -1 (10 mg of catalyst), and the largest AQE (apparent quantum efficiency) can reach a high value of 26.26%. This work may afford progressive tactics to design multifunctional photocatalysts., (© 2023 Wiley-VCH GmbH.)