Fischer–Tropsch synthesis (FTS) for the production of gasoline and middle distillates in the range of C5–C22 hydrocarbons was investigated using ZSM5-modified Co/SiO2 FTS catalysts. The Co/SiO2 catalyst was prepared by an impregnation method using a cobalt nitrate precursor in a slurry of SiO2, and theh ZSM5-modified Co/SiO2 catalyst was subsequently prepared by synthesizing ZSM5 (Si/Al ratio = 40) by in situ hydrothermal synthesis over the Co/SiO2 catalyst at different ZSM5/(Co/SiO2) weight ratios. The catalytic performance was largely altered by changing acidity and reducibility of cobalt oxides on ZSM5-modified Co/SiO2 catalysts due to the different extents of migration of cobalt oxides from SiO2 to the ZSM5 surface with different degrees of catalytic olefin cracking reaction. The ZSM5-modified Co/SiO2 catalyst with 25 wt %ZSM5 shows a maximum selectivity to C5–C22 hydrocarbons with a high CO conversion due to the smaller cobalt crystallite size possessing a high reducibility and optimum acid site density. The superior catalytic performance on the ZSM5-modified Co/SiO2 catalysts is mainly attributed to the modification of the Co/SiO2 surface with the presence of adjacent ZSM5 particles and the possible migration of cobalt species from SiO2 to the ZSM5 surface during the hydrothermal synthesis of ZSM5.

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The increasing demand for portable and wearable electronics has promoted the development of safe and flexible yarn–based batteries with outstanding electrochemical properties. However, achieving superior energy storage performance with a high active material (AM) load and long cycle life with this device format remains a challenge. In this study, a stable and rechargeable high–performance aqueous Ni–Fe yarn battery was constructed via biscrolling to embed AMs within helical carbon nanotube (CNT) yarn corridors. Owing to the high load of charge storage nanoparticles (NPs; above 97 wt%) and the outer neat CNT layer, the buffered biscrolled Ni–Fe yarn battery demonstrates excellent linear capacity (0.053 mAh/cm) and cycling stability (60.1% retention after 300 charge/discharge cycles) in an aqueous electrolyte. Moreover, our flexible yarn battery exhibits maximum energy/power densities of 422 mWh/cm3 and 7535 mW/cm3 based on the total volume of the cathode and anode, respectively, which exceed those reported for many flexible Ni–Fe batteries. Thus, biscrolled Ni–Fe yarn batteries are promising candidates for next–generation conformal energy solutions.