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We present a simple approach for the fabrication of a full-thickness super-hydrophobic composite coating consisted of modified TiO 2 nanoparticles and polysiloxane resin. Scanning electron microscope (SEM), fourier transform infrared spectrometer (FTIR), contact angle meter and a simple self-made device were employed to characterize the surface morphologies, chemical compositions, contact angle and sliding angle of the modified TiO 2 nanoparticles and composite coating, respectively. Results show that for both the modified TiO 2 nanoparticles and the as-prepared composite coating the contact angle and sliding angle of is up to 152° and 0°, respectively. In addition, due to the coating design of full-thickness super-hydrophobicity, the composite coating also exhibited good thermal stability, abrasion resistance and corrosion resistance in the thermo-gravimetric analysis (TGA) experiment, abrasion test and immersion test, respectively.

Smart coatings depending on external nanocontainers are often complex and expensive, which can only inhibit local corrosion depending on the microenvironment change after corrosion. In this work, nanocatalytic anticorrosion based on silica coated nitrogen enriched hollow carbon spheres (NHCs@mSiO2) is developed to achieve the prolongation of coating lifetime and long-term protection of metals. Obtained NHCs@mSiO2 by confined space pyrolysis strategy shows a double-shelled hollow structure with interior N-doped carbon shell and exterior silica shell. Moreover, the NHCs@mSiO2 spheres possess favorable catalytic ability for oxygen thanks to the incorporation of nitrogen. When blended into epoxy coatings, amphiphilic NHCs@mSiO2 spheres distribute uniformly and occupy the pores or cracks in composite coatings. The diffused oxygen through coating micropores are preferentially adsorbed by NHCs@mSiO2 and directly reduced to water through four-electron pathways. Therefore, the corrosion is greatly avoided due to the depletion of oxygen. The introduction of nano-catalyst with excellent dispersity and oxygen reduction ability will pave the way toward the development of new smart coatings with active corrosion resistance.

Developing high-performance materials for efficient isolation of proteins is of great importance. Herein, the authors synthesized a series of magnetic Fe3O4@PS-ANTA-M2+ (M = Ni, Co, Cu and Zn) nanospheres, consisting of fine Fe3O4 nanoparticles encapsulated by functionalized polystyrene shell, where metal ions were complexed by Nα, Nα-Bis(carboxymethyl)-L-lysine hydrate for selectively immobilizing histidine (His)-tagged proteins. The structures of the Fe3O4@PS-ANTA-M2+ were studied by field scanning electron microscopy, transmission microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy and vibrating sample magnetometer. The adsorption performance of the Fe3O4@PS-ANTA-M2+ was studied using bovine hemoglobin as a model protein. The thermodynamics of the binding process was studied by isothermal titration calorimetry tests. The resulting Fe3O4@PS-ANTA-Cu2+, Fe3O4@PS-ANTA-Ni2+, Fe3O4@PS-ANTA-Co2+ and Fe3O4@PS-ANTA-Zn2+ possessed adsorption capacities of 21200, 8080, 6640 and 5360 mg g−1, respectively, rendering them as the best adsorbents for protein purification. The adsorption isotherm was better fitted by Langmuir equation. To verify the selectivity, the Fe3O4@PS-ANTA-M2+ was practically employed to isolate His-tagged proteins from cell lysate. The results indicated that the samples showed outstanding adsorption capacity, selectivity and stability, and facile regeneration and separation, outperforming a commercial NTA-Ni column. These findings suggested that the Fe3O4@PS-ANTA-M2+ showed promising applications for specifically isolating proteins from complex biological systems.

Most of existing nanocontainers suffer from tedious, complicated and unsustainable assembly process which restricts their application in corrosion protection as smart inhibitor carriers. In this study, we adopted the framework-hybridization approach to prepare a smart anticorrosion system (MBT@Ph-HPMO), with MBT inhibitor as cargo and phenylene-bridged hollow periodic mesoporous organosilica (Ph-HPMO) as nanocontainer. Results reveal that the π-π stacking between MBT and framework of Ph-HPMO serves as nature valve, which is supplemented by the molecular dynamic simulation. The encapsulated inhibitor was loaded into Ph-HPMO at neutral pH, demonstrating fast release in acidic environment. On-demand release of inhibitors from MBT@Ph-HPMO contributed to achieving in situ active corrosion protection. Anticorrosion performance of MBT@Ph-HPMO for copper alloy was evaluated in 3.5 wt% NaCl solution for a period of 30 days. The alloy exhibited the slightest corrosion damage in the corrosion medium with the addition of 0.24 wt% MBT@Ph-HPMO. This facile and versatile strategy will have broad applications in new class of nanocontainers fabrication and open up a new prospect for active corrosion protection.