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Grapefruit peel carbon (GPC) is prepared from waste grapefruit peel and further used as substrate for in situ construction of MoS2 arrays, forming MoS2/GPC heterostructured materials. Based on the effect of the mass ratio between MoS2 and GPC on the morphology and structure, it can be found that the mass ratio not only has an important impact on the morphology and structure of MoS2, but also further affects the energy storage performance when used as the anode in lithium-ion batteries. Under the optimal mass ratio of 3:1, flower-like MoS2 is uniformly dotted on the GPC surface, presenting a special heterostructure, which has been successfully synthesized via the hydrothermal method. The electrochemical study shows that the MoS2/GPC composite obtained exhibits satisfying charge–discharge stability and rate capability thanks to the short diffusion channel for lithium ions and very low charge transfer resistance. Electrochemical impedance spectroscopy at different states of charge reveals that the passivation layer formed in the initial stage plays an important role in maintaining the stability of the electrode.

Hexagonal molybdenum trioxide (h-MoO3) nanoparticles with a particle size of several tens of nanometers were prepared from sodium molybdate (Na2MoO4) using hydrothermal synthesis and ultrasonication. The morphology, structure, composition, and chemical states of the nanoparticles were characterized by x-ray diffraction, field-emission scanning electron microscopy, and Fourier transform-infrared spectroscopy. Cyclic voltammetry results showed a strong reduction peak, which indicated a lithium ion insertion/extraction mechanism. The plateau observed in the first discharge curve around 1.8 V was in accordance with the above mechanism, which was also verified by differential capacity measurements. Cycling performance results showed that the capacity retention was up to 90% in the second cycle and that the irreversible capacities decreased with subsequent cycles.

Er-doped LiV3O8 as cathode material for secondary lithium batteries was prepared through a rheological phase reaction method. The as-prepared materials were investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), and galvanostatic discharge/charge measurements. The results indicate that Er doped phase preserves the layered structure of the pristine LiV3O8 and has an enlarged interlayer spacing. Compared to LiV3O8 sample, Er-doped LiV3O8 sample displays more uniform particles and large surface area. The electrochemical test shows that Er doping does not change the process of Li+ insertion/deinsertion. Er-doped LiV3O8 electrode exhibits an initial discharge capacity of 294.2 mAh g−1 and maintains a stable capacity of 220.7 mAh g−1 after 50 cycles, indicating a greatly improved good cycleability comparing with the undoped one.

A series of metal–acid bifunctional catalysts with varying quantities of platinum and tungstophosphoric acid (TPA) supported on zirconium oxide were prepared by co-impregnation method. In skeletal isomerization of n-pentane using catalyst with 1% Pt and 30% TPA loadings the conversion of the reactant which was close to the equilibrium conversion reached ca. 65% and the selectivity towards the product was as high as ca. 97% at atmospheric pressure and relatively low reaction temperature (200 °C). The phase structure, chemical structure, surface physicochemical properties, surface element oxidation states and hydrogen reduction behavior of the catalysts were well-characterized via XRD, FT-IR, N2 adsorption–desorption determination (BET), XPS and TPR. The effects of Pt and TPA loadings, calcination temperature, reaction temperature and weight hourly space velocity (WHSV) on the catalytic performance were investigated. In addition, a long period catalytic stability test of the catalyst with optimal Pt and TPA loadings was carried out, which indicated that the bifunctional catalyst was in possession of good stability in skeletal isomerization along with high catalytic activity under the experimental conditions.

Skeletal isomerization of n-pentane in the presence of hydrogen has been studied over Pt-promoted H3PW12O40 (TPA)/MCM-41 bifunctional catalyst. A series of solid acid catalysts with different loading amount of TPA and Pt were prepared and characterized by XRD, FT-IR and XPS. The optimal catalytic activity of Pt-TPA/MCM-41 was observed with 2% Pt and 30% TPA. According to the cracked products distribution, this is typical of a monomolecular bifunctional metal-acid mechanism. Further, catalysts with different combination of noble metals (Pt, Pd and Ru), heteropoly acids (HPAs) (TPA, tungstosilicic acid (TSA), and molybdophosphoric acid (MPA)) and supports (MCM-41, SBA-1 and SiO2) were also synthesized and their catalytic performances were compared.