Spacing Of Nanoparticles Research Articles

Boosting the Efficiency of Low-Cost T-C-O-Less Dye-Sensitized Solar Cells Employing Nanoparticle Spacers and Cobalt Complex Redox Shuttle

A strategy has been explored to enhance the diffusion of Co2+/3+ species through the dye-stained nanoparticle spacer employed as an electrolyte absorbing layer with different nanoparticle sizes of ...

Strengthened magnetic epoxy nanocomposites with protruding nanoparticles on the graphene nanosheets

Magnetic graphene (Gr) nanocomposites (Gr nanosheets coated with iron core iron oxide shell nanoparticles, named Gr/Fe@Fe2O3) have successfully served as nanofillers for obtaining magnetic epoxy resin polymer nanocomposites (PNCs) to be compared with the epoxy nanocomposites with pure graphene. The effects of nanofiller loading levels on the rheological behaviors, thermal stability, thermo-mechanical, tensile mechanical properties, electrical conductivity and magnetic properties were systematically studied. A reduced viscosity was observed in the 1.0 wt% Gr–epoxy resin liquid nanosuspensions and the viscosity was increased with further increasing the Gr loading. In the TGA test, although the introduction of both nanofillers caused lower onset decomposition temperature of the PNCs, the Gr/Fe@Fe2O3 was found to favor the char formation from the epoxy resin. The enhanced char residue was also observed during the flammability tests. The dynamic storage and loss modulii were studied together with the glass transition temperature (Tg) obtained from the peak of tanδ. The tensile strength observed in the PNCs with 1.0 wt% Gr/Fe@Fe2O3 is 58% higher than that of the pure epoxy, and was attributed to the high stiffness of Gr. Both nanofillers could increase the electrical conductivity of the epoxy matrix. The magnetic properties of the PNCs with Gr/Fe@Fe2O3 are studied and the value of coercivity (Hc) is observed inversely proportional to the loading of Gr/Fe@Fe2O3 in the PNCs due to the decreased interparticle dipolar interaction, which arises from the enlarged nanoparticle spacer distance for the single domain nanoparticles. Finally, the increased real permittivity observed in the PNCs is attributed to the interfacial polarization.

Iron-core carbon-shell nanoparticles reinforced electrically conductive magnetic epoxy resin nanocomposites with reduced flammability

Carbon coated iron (Fe@C) nanoparticles successfully served as nanofillers for obtaining magnetic epoxy resin polymer nanocomposites (PNCs). The effects of nanofiller loading level on the rheological behaviors, thermal stability, flammability, dynamic mechanical, mechanical properties, electrical conductivity and magnetic properties were systematically studied. And the curing process of the PNCs was also studied by Fourier transform infrared spectroscopy test. A reduced viscosity was observed in the 1.0 wt% Fe@C/epoxy resin liquid suspension samples and the viscosity was increased with further increasing the Fe@C nanoparticle loading. In the TGA test, the introduction of the Fe@C nanofillers gave a lower onset decomposition temperature of the PNCs. However, a reduced flammability was observed in the PNCs due to the easier char formation from epoxy matrix induced by the Fe@C nanoparticles. The dynamic storage and loss modulii were studied together with the glass transition temperature (Tg) being obtained from the peak of tanδ. Enhanced storage modulus was observed in the PNCs with 20.0 wt% Fe@C nanoparticles. The percolation thresholds of the Fe@C nanoparticles were identified with the study of tensile strength and electrical conductivity. Due to the cavities initiated by the nanoparticles, the PNCs with 5.0 wt% Fe@C nanoparticles showed an increased tensile strength up to 60% compared with pure epoxy. The Fe@C nanofillers could efficiently increase the electrical conductivity of the epoxy matrix, and the particle chain observed in the SEM image of fracture surface indicated the formation of percolated Fe@C nanoparticles in the epoxy matrix. Finally, the Fe@C nanoparticles become magnetically harder after dispersing in epoxy due to the decreased interparticle dipolar interaction, which arises from the enlarged nanoparticle spacer distance for the single domain nanoparticles.