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The key factors governing the single-phase or multi-phase structural change behaviors during the intercalation/deintercalation of guest ions have not been well studied and understood yet. Through systematic studies of orthorhombic Fe2(MoO4)3 electrode, two distinct guest ion occupation paths, namely discrete one for Li and pseudo-continuous one for Na, as well as their relationship with single-phase and two-phase modes for Na+ and Li+, respectively during the intercalation/deintercalation process have been demonstrated. For the first time, the direct atomic-scale observation of biphasic domains (discrete occupation) in partially lithiated Fe2(MoO4)3 and the one by one Na occupation (pseudo-continuous occupation) at 8d sites in partially sodiated Fe2(MoO4)3 are obtained during the discharge processes of Li/Fe2(MoO4)3 and Na/Fe2(MoO4)3 cells respectively. Our combined experimental and theoretical studies bring the new insights for the research and development of intercalation compounds as electrode materials for secondary batteries.

A novel in situ time-resolved synchrotron X-ray absorption spectroscopy (XAS) was introduced for the dynamic studies during fast chemical and electrochemical delithiation of LiFePO(4). The lithium diffusion in LiFePO(4) and the reaction mechanisms for both processes were investigated. This approach opens new opportunities for dynamic studies of various energy storage systems.

CuCoO2 nanoplates were prepared through the solvothermal method at 140 °C using ZIF-67 as the Co precursor for the first time.

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ZnGa 2 O 4 powder, synthesized by a solid state method, exhibit efficient photocatalytic activity for rhodamine B (RhB) degradation under mercury lamp illumination.However, the photocatalytic activity of ZnGa 2 O 4 was highly suppressed due to Cr 3+ ions doping. We discussed the mechanism of photocatalysis based on the photoluminescence properties of ZnGa 2 O 4 and ZnGa 2 O 4 :Cr 3+ , and the blue fluorescence lifetimes of host ZnGa 2 O 4 with different Cr 3+ concentrations were also measured. The results indicated that Cr 3+ ions doping are act as recombination centers, which can highly reduce the amount and lifetime of the electron-hole pairs and thus reduce the photocatalytic activity of ZnGa 2 O 4 . The thermoluminescence (TL) curves of ZnGa 2 O 4 and ZnGa 2 O 4 :Cr 3+ showed that the amount of trapped electrons/holes in ZnGa 2 O 4 is almost seven times higher than that of ZnGa 2 O 4 :Cr 3+ . The suppressed long-lasting luminescence intensity and photocatalytic activity of ZnGa 2 O 4 :Cr 3+ were supposed to come from the decrease of trapped electrons/holes and shortened lifetime of the electron-hole pairs. Possible mechanisms of long-lasting luminescence and photocatalysis of ZnGa 2 O 4 coupled with photoluminescence mechanisms of ZnGa 2 O 4 :Cr 3+ were also proposed.