Hollow carbon nanofibers with hierarchical porous shells were prepared by NaOH activation of the electrospinning SiCNO fibers, followed by carbonization treatment. By adjusting the carbonization temperature, porous hollow carbon nanofibers with different Brunauer−Emmett−Teller (BET) specific surface areas and total pore volumes are obtained, both of which are explored as electrode materials for supercapacitors. It was found that the obtained products (HCF800) possess the highest BET specific surface area of 2628.10 m 2 /g and the largest pore volume of 2.32 cm 3 /g when the carbonized temperature was designed at 800 °C, thus displaying the best supercapacitor performance. The electrochemical results in a three-electrode system show that HCF800 exhibits a high specific capacitance of 330.11 F/g as the discharge current density is 1 A/g and still maintains 65.3% of its original specific capacitance when the current density reaches 20 A/g. Moreover, in a twoelectrode system, HCF800 also exhibits an excellent specific capacity of 259.86 F/g at a current density of 1 A/g, marvelous cyclic stability with the specific capacitance retention of 95.3% even after 10,000 cycles, and a large energy density of 12.99 W h/kg at 1.0 A/g. Significantly, the supercapacitor performance of these porous hollow carbon nanofibers is also superior to that of many previously reported carbon materials, which proved them to be worthy candidates for high-performance electrode materials.

Mixed matrix membrane (MMM) structures and performances are greatly affected by the distribution of nanoparticles in the polymeric matrix. Until now, there has been little research on the effects of nanoparticle distribution states on polyacrylonitrile (PAN)‐based MMM structures and performances. In this paper, different intermolecular interactions between nanoparticles and PAN molecules were generated by in situ fabricated amino‐functionalized SiO2 and TiO2 nanoparticles to create absolutely different distribution states of nanoparticles in a PAN matrix. The results indicated that, due to the strong interactions between amino and cyano groups, SiO2 is distributed in the PAN membranes homogeneously, while most of the TiO2 migrates to the membrane's top surfaces or the walls of pores or even escape from the membranes during the nonsolvent index phase separation (NIPS) process. PAN‐TiO2 MMMs have more hydrophilic top surfaces, higher porosity, larger mean pore size, and stronger antifouling performances than pure PAN and PAN‐SiO2 membranes. The PAN‐TiO2 MMMs have an ultrahigh water flux of 1204.6 L/(m2 h), which is more than 44 times that of PAN membranes. And the good pore structures and hydrophilicity of the membranes derived from special interactions between in situ TiO2 nanoparticles and PAN molecules can give high‐performance PAN‐based ultrafiltration membranes a bright future. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47902.

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