Fabrication of Hierarchical Macroporous/Mesoporous Carbons via the Dual-Template Method and the Restriction Effect of Hard Template on Shrinkage of Mesoporous Polymers

A series of hierarchically ordered macro-<b>/</b>mesoporous polymer resins and macro-<b>/</b>mesoporous carbon monoliths were synthesized using SiO₂ opal as a hard template for the macropore, amphiphilic triblock copolymer PEO–PPO–PEO as a soft template for the mesopore, and phenolic resin as a precursor for the polymer or carbon. The obtained hierarchical macro-<b>/</b>mesoporous frameworks had highly periodic arrays of uniform macropores that were surrounded by walls containing the mesoporous structures. The mesoporous structure of the walls was adjusted using different precursors for the synthesis of FDU-14, FDU-15, and FDU-16. Results of the N₂ adsorption–desorption analysis showed that the Brunauer–Emmett–Teller surface areas, the pore volumes, and the mesopore sizes of the macro-<b>/</b>mesoporous carbons were much larger than those of the FDU-14, FDU-15, and FDU-16 carbon materials. The mesopore size of the samples clearly increased with the increasing heat-treatment temperature when the temperature was below 700 °C. The results indicate that the SiO₂ hard template successfully restricted the shrinkage of the framework during the thermosetting and carbonization process

Improved Triboelectric Nanogenerator Output Performance through Polymer Nanocomposites Filled with Core–shell-Structured Particles

Core–shell-structured BaTiO₃–poly­(<i>tert</i>-butyl acrylate) (P<i>t</i>BA) nanoparticles are successfully prepared by in situ atom transfer radical polymerization of <i>tert</i>-butyl acrylate (<i>t</i>BA) on BaTiO₃ nanoparticle surface. The thickness of the P<i>t</i>BA shell layer could be controlled by adjusting the feed ratio of <i>t</i>BA to BaTiO₃. The BaTiO₃–P<i>t</i>BA nanoparticles are introduced into poly­(vinylidene fluoride) (PVDF) matrix to form a BaTiO₃–P<i>t</i>BA/PVDF nanocomposite. The nanocomposites keep the flexibility of the PVDF matrix with enhanced dielectric constant (∼15@100 Hz) because of the high permittivity of inorganic particles and the ester functional groups in the P<i>t</i>BA. Furthermore, the BaTiO₃–P<i>t</i>BA/PVDF nanocomposites demonstrate the inherent small dielectric loss of the PVDF matrix in the tested frequency range. The high electric field dielectric constant of the nanocomposite film was investigated by polarization hysteresis loops. The high electric field effective dielectric constant of the nanocomposite is 26.5 at 150 MV/m. The output current density of the nanocomposite-based triboelectric nanogenerator (TENG) is 2.1 μA/cm², which is above 2.5 times higher than the corresponding pure PVDF-based TENG

Self-Powered Electrospinning System Driven by a Triboelectric Nanogenerator

Broadening the application area of the triboelectric nanogenerators (TENGs) is one of the research emphases in the study of the TENGs, whose output characteristic is high voltage with low current. Here we design a self-powered electrospinning system, which is composed of a rotating-disk TENG (R-TENG), a voltage-doubling rectifying circuit (VDRC), and a simple spinneret. The R-TENG can generate an alternating voltage up to 1400 V. By using a voltage-doubling rectifying circuit, a maximum constant direct voltage of 8.0 kV can be obtained under the optimal configuration and is able to power the electrospinning system for fabricating various polymer nanofibers, such as polyethylene terephthalate (PET), polyamide-6 (PA6), polyacrylonitrile (PAN), polyvinylidene difluoride (PVDF), and thermoplastic polyurethanes (TPU). The system demonstrates the capability of a TENG for high-voltage applications, such as manufacturing nanofibers by electrospinning

Self-Powered Electrospinning System Driven by a Triboelectric Nanogenerator

Broadening the application area of the triboelectric nanogenerators (TENGs) is one of the research emphases in the study of the TENGs, whose output characteristic is high voltage with low current. Here we design a self-powered electrospinning system, which is composed of a rotating-disk TENG (R-TENG), a voltage-doubling rectifying circuit (VDRC), and a simple spinneret. The R-TENG can generate an alternating voltage up to 1400 V. By using a voltage-doubling rectifying circuit, a maximum constant direct voltage of 8.0 kV can be obtained under the optimal configuration and is able to power the electrospinning system for fabricating various polymer nanofibers, such as polyethylene terephthalate (PET), polyamide-6 (PA6), polyacrylonitrile (PAN), polyvinylidene difluoride (PVDF), and thermoplastic polyurethanes (TPU). The system demonstrates the capability of a TENG for high-voltage applications, such as manufacturing nanofibers by electrospinning

Self-Powered Electrospinning System Driven by a Triboelectric Nanogenerator

Broadening the application area of the triboelectric nanogenerators (TENGs) is one of the research emphases in the study of the TENGs, whose output characteristic is high voltage with low current. Here we design a self-powered electrospinning system, which is composed of a rotating-disk TENG (R-TENG), a voltage-doubling rectifying circuit (VDRC), and a simple spinneret. The R-TENG can generate an alternating voltage up to 1400 V. By using a voltage-doubling rectifying circuit, a maximum constant direct voltage of 8.0 kV can be obtained under the optimal configuration and is able to power the electrospinning system for fabricating various polymer nanofibers, such as polyethylene terephthalate (PET), polyamide-6 (PA6), polyacrylonitrile (PAN), polyvinylidene difluoride (PVDF), and thermoplastic polyurethanes (TPU). The system demonstrates the capability of a TENG for high-voltage applications, such as manufacturing nanofibers by electrospinning