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FePS3, a classical 2D layered material with transition metal phosphorous trichalcogenides, was investigated as an anode material for Mg ion batteries. We used density functional theory to calculate the Mg storage properties of FePS3, such as Mg adsorption energy, theoretical specific capacity, average voltage, diffusion energy barriers, volume change, and electronic conductivity. The theoretical specific capacity of the FePS3 monolayer is 585.6 mA h/g with a relatively low average voltage of 0.483 V (vs. Mg/Mg2+), which is favorable to a high energy density. The slight change in volume and good electronic conductivity of bulk FePS3 are beneficial to electrode stability during cycling.

A novel amorphous FeOOH modified BiVO4 photocatalyst (A-FeOOH/BiVO4) was successfully produced and characterized by various techniques. The results showed that amorphous FeOOH with about 2 nm thickness evenly covered on BiVO4 surface, which caused resultant A-FeOOH/BiVO4 exhibiting higher visible light photocatalytic performance for producing O2 from water than BiVO4. When the covered amount of amorphous FeOOH was 8%, the resultant photocatalyst possessed the best photocatalytic performance. To find the reasons for the improvement of photocatalytic property, electrochemical experiments, DRS, PL and BET, were also measured, the experimental results indicated that interface effect between amorphous FeOOH and BiVO4 could conduce to migration of photogenerated charge, and exhibit stronger light responded capacity. These positive factors promoted A-FeOOH/BiVO4 presenting improved the photocatalytic performance. In a word, the combination of amorphous FeOOH with BiVO4 is an effective strategy to conquer important challenges in photocatalysis field.

Ternary MoS2/MoO3/C nanosheets were successfully synthesized via a chemical vapor deposition method. The hybrids were characterized by x-ray diffraction, scanning electron microscope, high-resolution transmission electron microscopy, raman and x-ray photoelectron spectroscopic methods. The as-obtained MoS2/MoO3/C nanosheets applied as an anode material for lithium-ion batteries, showed high initial discharge/charge capacities at current rates of 0.5C, 1640.9 mA h g−1 and 1393.8 mA h g−1 respectively, with initial coulombic efficiency of approximately 84.9%. The material exhibited superior rate capabilities, with specific discharge capacities of 1240.2 mA h g−1, 1048.5 mA h g−1, 917.2 mA h g−1, 742.3 mA h g−1, 663.6 mA h g−1, 601.8 mA h g−1 and 593.4 mA h g−1 at current rates of 0.2C, 0.4C, 1C, 4C, 8C, 12C and 15C, respectively. This superior electrochemical performance was mainly due to the uniformly-distributed MoS2 nanosheets and to highly graphitized carbon, which not only mitigated mechanical stress during repeated cycling, but also provided good conductivity.

Nanostructured LiFePO4/C cathode material was prepared by FePO4·2H2O/C precursor by in situ restriction reaction. The synthesized LiFePO4/C cathode material presents a narrow distribution of nano-sized particles and exhibits an excellent electrochemical property with various rates. The facile synthesis route for the preparation of nano-sized LiFePO4 material has the particular advantage of simple synthesis process and low synthesis cost.

Layered LiCo1/3Ni1/3Mn1/3O2 has been modified with Co–Al-mixed metal oxide (CoAl-MMO). The surface-modified materials were characterized by X-ray diffraction, field emission scanning electron microscopy, and galvanostatic charge–discharge cycling. The CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 had an initial discharge specific capacity of 178.1 mAh g−1 within the potential range of 2.75–4.5 V (vs. Li+/Li), and its discharge specific capacity is 175.0 mAh g−1 after 50 cycles, much higher than that of the pristine LiCo1/3Ni1/3Mn1/3O2 (148.4 mAh g−1). The improvement could be attributed to the CoAl-MMO coating layer that would hinder interaction between LiCo1/3Ni1/3Mn1/3O2 and electrolyte and stabilize the structure of LiCo1/3Ni1/3Mn1/3O2. Moreover, DSC showed that the CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 had a higher thermal stability than the pristine LiCo1/3Ni1/3Mn1/3O2. Therefore, the CoAl-MMO-coated LiCo1/3Ni1/3Mn1/3O2 could be a high-performance cathode material for lithium-ion batteries.