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Flexible, low-density, high-performance electromagnetic interference (EMI) shielding performance materials are urgently required in aerospace and flexible electronic devices. Due to the high aspect ratio and conductivity, carbon nanotube (CNTs) has been considered as one of the most promising candidates for providing excellent EMI shielding performance. Here, a flexible spongy CNTs consisting of self-assembled, interconnected CNT skeletons, with a density of 10.0 mg/cm 3 , was directly used as EMI shielding film. The freestanding CNT sponge with a thickness of 1.8 mm shows highly EMI shielding effectiveness (SE) and specific SE (SSE) of 54.8 dB and 5480 dB cm 3 /g in X-band, respectively. The performance of the CNT sponges can be further improved by increasing the thickness or density of the samples. After composited with PDMS by directly infiltrating method, the CNT/PDMS film still exhibits excellent EMI SE (46.3 dB) at the thickness of 2.0 mm, while the CNT loading content is less than 1.0 wt%. The EMI SE of the composite is almost unchanged after repeated stretching or bending for 1000 cycles. The flexible, stability, and highly conductive nanocompsite can be directly used as high-performance EMI shielding films in areas such as packaging, electronics and communication. [ABSTRACT FROM AUTHOR]

Abstract Porous, spongy absorbers are considered to be the most promising candidates for lightweight and highly efficient microwave absorption material. However, conventional sponges or foams reported previously are difficult to meet the high performance requirements. Here, a lightweight (42 mg/cm3), porous CNT@TiO 2 sponge with core-shell structure CNT/TiO 2 was successfully prepared via a simple combination of hydrolysis and heat treatment method. In the sponge, the thickness and crystal structure of the TiO 2 shell layer, and the mass fraction of TiO 2 and CNTs can be precisely controlled by the growth processes, resulting in adjustable dielectric loss properties of the samples. With the optimized component proportion, it was found that a minimum reflection loss value of −31.8 dB was observed at 10.35 GHz, and reflection loss exceeds −10 dB is up to 2.76 GHz for the absorber with the thickness of 2 mm. Moreover, the effective microwave absorption (<10 dB) can be achieved in the range of 3.43–12.0 GHz by adjusting the thickness of the absorber. These results indicate that the CNT@TiO 2 sponges can serve as attractive candidate materials for lightweight microwave absorption materials. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

This study presents a catalytic membrane based on cobalt-loaded carbon nanotubes and graphene oxide (Co@CNT-GO). Cobalt, serving as the active center, efficiently activates peroxymonosulfate for the degradation of organic compounds in transmembrane water. The uniform dispersion and firm loading of Co on CNT prevent the aggregation and leakage issues typically associated with conventional catalysts. The two-dimensional channels formed by the vacuum-assisted self-assembly of CNT and GO enhance the probability of contact between organic compounds and Co and prolong the contact duration thereby ensuring catalytic efficiency while maintaining a low water permeability resistance. The water flux of the catalytic membrane is 90 L/m2/h, and the atrazine removal efficiency is more than 92%, maintaining high stability even after continuous operation for 72 h. The generated active free radicals, including sulfate radicals, hydroxyl radicals, and singlet oxygen, synergistically facilitate the mineralization of organic compounds. Furthermore, the presence of oxygen vacancies on CNT accelerates the redox cycle of ≡ Co(II)/≡Co(III), sustaining the catalytically active center. Compared to the precursor catalytic membrane, Co@CNT-GO catalytic membrane possesses the characteristics of high removal efficiency and high flux, holding promise as a platform technology for the rapid and precise treatment of organic pollutants in contaminated water. [Display omitted] • Membranes are prepared via vacuum-assisted self-assembly of Co@CNT-GO. • Catalytic oxidation process occurs in 2D nanochannels filled with 1D nanotubes. • Co@CNT-GO membrane achieves almost 100% removal of ATZ within 175 ms. • Oxygen vacancies accelerate the redox cycle of ≡ Co(II)/≡Co(III). [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) decorated with ferromagnetic materials have promising potential in electromagnetic interference (EMI) shielding applications. In this work, CNT sponges with increasing density were fabricated by filling them with magnetic Fe nanowires of mutative filling ratios via chemical vapor deposition (CVD). Results indicated that Fe@CNT composites with the highest density endowed the most remarkable average SE T value of 70.01 dB (more than 99.99999% absorption), showing an ultra-high EMI shielding performance. However, the susceptibility to oxidation of carbon materials has restricted its further development in high-temperature EMI shielding applications. Therefore, the Fe@CNT composites were encapsulated by silicon carbide (SiC) with satisfactory oxidation resistance. Thereafter, the average SE T value of SiC encapsulated a higher density Fe@CNT sponge decreased to an adequate value of 36.48 dB due to the huge loss of electrical conductivity. However, the SE T value of it only dropped by about 1.20 as the temperature went up from 25 to 600 °C, demonstrating an excellent stability under high temperature conditions. As a proof of concept, the Fe@CNT/SiC composites with adequate EMI shielding performance and satisfactory oxidation resistance suggest its prospect in high temperature resistant EMI shielding. [ABSTRACT FROM AUTHOR]