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Nanoscale complex-shaped colloids with tunable morphologies and fascinating properties have attracted the attention of numerous scientists for decades. Exploring facile synthetic strategies has always been the target for the large-scale production and practical use of these remarkable materials. Herein, we developed a one-step strategy to fabricate raspberry-like hollow periodic mesoporous organosilica (RHPMO) with tunable surface structures and specific surface area as high as 1628 m2 g−1. Unexpectedly, this preparation method shares a similar protocol as that of the classical one to make spherical PMO. The dynamic formation process of RHPMO has been detected by TEM. PMOs with solid cores were formed at the first stage, followed by a hollowing process owing to the tension of condensation among the silica precursor molecules. The final RHPMO nanoparticles were generated by controlling the condensation and the adsorption of the as-formed precursor/surfactant assemblies and covalently bonding them subsequently onto the surface of the core. The size of corona particles increased with the concentration of NH3·H2O, while low reaction temperatures were beneficial for the formation of RHPMO instead of spherical HPMO (SHPMO). A superhydrophobic coating was realized by depositing fluorine-modified RHPMO layers onto the glass substrate. The measured contact angle reached 153.9°. This one-step strategy for fabricating RHPMO may bring the new understandings of the formation mechanism of PMO and is expected to serve as a facile way for the large-scale production of raspberry-like functional silica spheres, which will thus open gates for more targeted applications.

Polyurethane/multiwalled carbon nanotube (PU/MWCNT) composite foams containing MWCNTs with long length (MWCNT-L and Ni@MWCNT-L) and MWCNTs with short length (MWCNT-S) were prepared using an environ...

Engineering high performance cellular ceramics with both ultralow density and satisfactory compressive strength for practical applications still represents a grand challenge. Herein, alumina-based cellular ceramics bonded by in-situ formed mullite phase were constructed by Al2O3–Si-boehmite particle-stabilized foams. The gelation of boehmite sol improved the stability and harnessed the deformation of dried Al2O3–Si composite foam. The oxidation of silicon and further generation of in-situ mullite phase enhanced the chemical bond between alumina particles on cell walls, resulting in the superior mechanical properties. As an exemplar, the resulting cellular ceramic possessed the robust compressive strength of 2.26 MPa at a high porosity of 87.8%. The gelation-assisted Al2O3–Si particle-stabilized foams provide a facile and convenient strategy for construction of composite ceramic foams with high porosity and robust strength.

Ingenious microstructure design and appropriate multicomponent strategies are still challenging for advanced electromagnetic interference (EMI) shielding materials with excellent shielding effectiveness (SE) and reliable mechanical properties in harsh environments and low filling levels. In this study, nickel@multiwalled carbon nanotubes/alumina (Ni@CNTs/Al