Cation‐Exchange‐Induced Metal and Alloy Dual‐Exsolution in Perovskite Ferrite Oxides Boosting the Performance of Li‐O₂ Battery

Abstract

Atemperature-controlled cation-exchange approach is introduced to achieve aunique dual-exsolution in perovskite La 0.8 Fe 0.9 Co 0.1 O 3Àd where both CoFea lloy and Co metal are simultaneously exsolved from the parent perovskite,f orming an alloya nd metal co-decorated perovskite oxide.M ossbauer spectra showt hat cation exchange of Fe atoms in CoFea lloy and Co cations in the perovskite is the key to the co-existence of Co metal and CoFealloy. The obtained composite exhibits an enhanced catalytic activity as Li-O 2 battery cathode catalysts with as pecific discharge capacity of 6549.7 mAh g À1 and ac ycling performance of 215 cycles without noticeable degradation. Calculations showt hat the combination of decorated CoFea lloya nd Co metal synergistically modulated the discharge reaction pathway that improves the performance of Li-O 2 battery.

Modulating Tit2gOrbital Occupancy in a Cu/TiO2Composite for Selective Photocatalytic CO2Reduction to CO

“…It is clear that a slight left shift of the Cu−Cu distance peak occurs for the Cu/TiO 2 ‐3 and this suggests that the Cu−Cu distance of Cu/TiO 2 ‐3 is relatively shorter compared with those of Cu/TiO 2 ‐2 and Cu/TiO 2 ‐4 [35] . This phenomenon demonstrates that the strong interaction between Cu and TiO 2 not only changes the orbital occupancy of Ti, but also modifies the local structure of Cu [36, 37] . This also reflects that the structure of the sample is related to the extent of combination.…”

Cobalt–Nickel Double Hydroxide toward Mild Aqueous Zinc‐Ion Batteries

“…XPS O 1s spectra for the samples are shown in Figure 4c, which can be fitted to three O‐containing compounds, i.e., HOH at ≈533 eV, metal(Co/Ni)OH at about 531.7 eV, and metalOmetal at ≈529.8 eV. [ 27a,43 ] The content ratio of metalOH/metalOmetal decreased significantly during charging from 1.3 to 1.85 V (Figure 4c,e), suggesting the transformation from metalOH to metalOmetal (H + deinsertion), in agreement with the XRD and SEM results. After further charging to 2.1 V, we did not observe obvious changes in morphology and crystal structure (Figure 4a,b).…”

Modulating Tit2gOrbital Occupancy in a Cu/TiO2Composite for Selective Photocatalytic CO2Reduction to CO

“…[35] This phenomenon demonstrates that the strong interaction between Cu and TiO 2 not only changes the orbital occupancy of Ti, but also modifies the local structure of Cu. [36,37] This also reflects that the structure of the sample is related to the extent of combination. The higher peak intensity of the CuÀ Cu distance in Cu/TiO 2 -3 indicates that the degree of disorder is lower.…”