This study reports the facile preparation and the dye removal efficiency of nanohybrids composed of graphene oxide (GO) and Fe3O4 nanoparticles with various geometrical structures. In comparison to previously reported GO/Fe3O4 composites prepared through the one-pot, in situ deposition of Fe3O4 nanoparticles, the GO/Fe3O4 nanohybrids reported here were obtained by taking advantage of the physical affinities between sulfonated GO and Fe3O4 nanoparticles, which allows tuning the dimensions and geometries of Fe3O4 nanoparticles in order to decrease their contact area with GO, while still maintaining the magnetic properties of the nanohybrids for easy separation and adsorbent recycling. Both the as-prepared and regenerated nanohybrids demonstrate a nearly 100% removal rate for methylene blue and an impressively high removal rate for Rhodamine B. This study provides new insights into the facile and controllable industrial scale fabrication of safe and highly efficient GO-based adsorbents for dye or other organic pollutants in a wide range of environmental-related applications.

Solvent vapor annealing (SVA) is originally developed to attain equilibrium nanostructures from microphase-separated block polymer thin films. Interestingly, by carefully choosing a solvent vapor that can selectively mobilize the amorphous chains of a semicrystalline polymer while preserving the integrity of its crystalline structure, this study demonstrates that the SVA method can also be utilized to introduce hierarchical structures onto semicrystalline polymer-based materials. This study on electrospun poly(ε-caprolactone) (PCL) fibers clearly shows that acetone, a poor solvent for PCL, can effectively delocalize the amorphous chains and redeposit them onto the pre-existing crystal edges, giving rise to secondary nanostructures inscribed onto the PCL fibers. In the past decade, various fiber fabrication methods and numerous fiber products are reported. The easy one-step approach reported here provides new insight into the design and fabrication of structurally hierarchical polymeric materials.

This paper reports the use of polyhedral oligomeric silsesquioxane (POSS)-based copolymers to stabilize the core/shell interface for the facile fabrication of electrospun core/shell fibers. For the poly[(propylmethacryl-heptaisobutyl-polyhedral oligomeric silsesquioxane)-co-(methyl methacrylate)] (POSS-MMA)/poly(ε-caprolactone) (PCL) system, the bicontinuity of hybrid core/shell fibers can be tuned by controlling the phase separation of POSS-MMA/PCL in electrospinning solutions and therefore the size of PCL-in-POSS-MMA emulsion droplets. Our results demonstrate the enhanced encapsulation capacity of POSS-MMA copolymers as shell materials. Taking advantage of the rapid advancement of POSS-based copolymer synthesis, this study can potentially be generalized to guide the fabrication of various other POSS-based core/shell nano-/microstructures by using single-nozzle electrospinning or coaxial electrospinning.

Back Cover: This study, for the first time, demonstrates that the solvent vapor annealing (SVA) method can be utilized to introduce structural hierarchy to PCL‐based fibers. The acetone vapor can delocalize amorphous chains and redeposit them onto the existing crystal edges, leading to hierarchically structured fibers. This facile approach provides new insight into the design and fabrication of hierarchical polymeric materials. Further details can be found in the article by J. Liu, A. J. P. Bauer, and B. Li* on page 1503.

This study reports polyhedral oligomeric silsesquioxane (POSS)-based hybrid fibers of architectural hierarchy and compositional heterogeneity.