• Energy Research

The high-temperature oxidation behaviour of oxide dispersion strengthened FeCrAl (ODS-FeCrAl) alloys was studied at 1100 °C in dry and wet atmospheres for use as candidate accident-tolerant fuel (ATF) cladding materials. Electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to analyze qualitatively and quantitatively the oxides microstructure of oxidized ODS-FeCrAl alloys. The oxidation rate of ODS-FeCrAl alloys in dry atmosphere was lower than that in wet atmosphere. The amount of nodular oxides were rich in Y, Zr, and Ti at the gas/scale interface in dry atmosphere was significantly larger than that in wet atmosphere. In addition, the grains size of columnar alumina formed on the alloy surface in dry atmosphere was larger than that in wet atmosphere. A mechanism of water vapour increasing the oxidation rate of ODS-FeCrAl alloys was well proposed.

We have effectively synthesized ZnS, FeSe2, and their nanocomposite using a straightforward and affordable solvothermal process. We also investigated for the first time their ideal electrochemical performance for supercapacitors. The ZnS and FeSe2 positive electrodes exhibit capacitances of 266.2 F g−1 and 294.3 F g−1, respectively, with fascinating nanostructures and morphology. Their respective nanocomposites, AZ-1, AZ-2, and AZ-3, deliver capacitances of 356.8, 444.4, and 326.1 F g−1 with significant rate performance in aqueous solution in a three-electrode assembly. The lowest ESR and Rct values of AZ-2 electrodes, which improved conductivity and charge transport kinetics and created a synergistic effect between ZnS and FeSe2 electrodes, are responsible for their exceptional capacitative performance. We built an asymmetric supercapacitor (AZ-2/AC) with an optimal voltage of 1.6 V, which demonstrated great power density (6250 W kg−1) and energy density (33 Wh kg−1) with remarkable cycling stability (88.1%) in an aqueous electrolyte after 12,000 cycles. As a result, FeSe2-based nanocomposites are strong contenders for realizing high energy and power delivery for practical applications.