Ultra-flexible and high-performance electromagnetic wave shielding film based on CNTF/liquid metal composite films

Room temperature liquid metal (LM) showcases a great promise in the fields of flexible functional thin film due to its favorable characteristics of flexibility, inherent conductivity, and printability. Current fabrication strategies of liquid metal film are substrate structure specific and sustain from unanticipated smearing effects. Herein, this paper reported a facile fabrication of liquid metal composite film via sequentially regulating oxidation to change the adhesion characteristics, targeting the ability of electrical connection and electrothermal conversion. The composite film was then made of the electrically resistive layer (oxidizing liquid metal) and the insulating Polyimide film (PI film) substrate, which has the advantages of electrical insulation and ultra-wide temperature working range, and its thickness is only 50 μm. The electrical resistance of composite film can maintain constant for 6 h and could work normally. Additionally, the heating film exhibited excellent thermal switching characteristics that can reach temperature equilibrium within 100 s, and recovery to ambient temperature within 50 s. The maximum working temperature of the as-prepared film is 115 °C, which is consistent with the result of the theoretical calculation, demonstrating a good electrothermal conversion capability. Finally, the heating application under extreme low temperature (−196 °C) was achieved. This conceptual study showed the promising value of the prototype strategy to the specific application areas such as the field of smart homes, flexible electronics, wearable thermal management, and high-performance heating systems.

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Ultrahigh Energy Storage Performances of Polymer-based Nanocomposite via Interfaces Engneering

Journal of Materials Chemistry A ◽

10.1039/d0ta10044g ◽

2020 ◽

Author(s):

Peng Wang ◽

Zhongbin Pan ◽

Weilin Wang ◽

Jianxu Hu ◽

Jinjun Liu ◽

...

Keyword(s):

Dielectric Constant ◽

Energy Storage ◽

High Performance ◽

Breakdown Strength ◽

Composite Films ◽

Power Electronic ◽

Ultrahigh Energy

High-performance electrostatic capacitors are in urgent demand owing to the rapidly development of advanced power electronic applications. However, polymer-based composite films with both high breakdown strength (Eb) and dielectric constant...

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Boosting Performance of Self-Polarized Fully Printed Piezoelectric Nanogenerators via Modulated Strength of Hydrogen Bonding Interactions

Nanomaterials ◽

10.3390/nano11081908 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1908

Author(s):

Hai Li ◽

Sooman Lim

Keyword(s):

Hydrogen Bonding ◽

Composite Film ◽

High Performance ◽

Composite Films ◽

Β Phase ◽

Hydrogen Bonding Interactions ◽

Barium Titanate Nanoparticles ◽

Surface Modified ◽

Piezoelectric Devices ◽

Piezoelectric Nanogenerators

Self-polarized piezoelectric devices have attracted significant interest owing to their fabrication processes with low energy consumption. Herein, novel poling-free piezoelectric nanogenerators (PENGs) based on self-polarized polyvinylidene difluoride (PVDF) induced by the incorporation of different surface-modified barium titanate nanoparticles (BTO NPs) were prepared via a fully printing process. To reveal the effect of intermolecular interactions between PVDF and NP surface groups, BTO NPs were modified with hydrophilic polydopamine (PDA) and hydrophobic 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTES) to yield PDA-BTO and PFD-BTO, respectively. This study demonstrates that the stronger hydrogen bonding interactions existed in PFD-BTO/PVDF composite film comparative to the PDA-BTO/PVDF composite film induced the higher β-phase formation (90%), which was evidenced by the XRD, FTIR and DSC results, as well as led to a better dispersion of NPs and improved mechanical properties of composite films. Consequently, PFD-BTO/PVDF-based PENGs without electric poling exhibited a significantly improved output voltage of 5.9 V and power density of 102 μW cm−3, which was 1.8 and 2.9 times higher than that of PDA-BTO/PVDF-based PENGs, respectively. This study provides a promising approach for advancing the search for high-performance, self-polarized PENGs in next-generation electric and electronic industries.

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Synthesis of silver nanoparticles embedded with single-walled carbon nanotubes for printable elastic electrodes and sensors with high stability

Scientific Reports ◽

10.1038/s41598-021-84386-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jae-Won Lee ◽

Joon Young Cho ◽

Mi Jeong Kim ◽

Jung Hoon Kim ◽

Jong Hwan Park ◽

...

Keyword(s):

Carbon Nanotubes ◽

Silver Nanoparticles ◽

High Performance ◽

Composite Films ◽

Single Walled Carbon Nanotubes ◽

Gauge Factor ◽

Time Interval ◽

Single Walled Carbon ◽

Irradiation Energy ◽

Walled Carbon Nanotubes

AbstractSoft electronic devices that are bendable and stretchable require stretchable electric or electronic components. Nanostructured conducting materials or soft conducting polymers are one of the most promising fillers to achieve high performance and durability. Here, we report silver nanoparticles (AgNPs) embedded with single-walled carbon nanotubes (SWCNTs) synthesized in aqueous solutions at room temperature, using NaBH4 as a reducing agent in the presence of highly oxidized SWCNTs as efficient nucleation agents. Elastic composite films composed of the AgNPs-embedded SWCNTs, Ag flake, and polydimethylsiloxane are irradiated with radiation from a Xenon flash lamp within a time interval of one second for efficient sintering of conductive fillers. Under high irradiation energy, the stretchable electrodes are created with a maximum conductivity of 4,907 S cm−1 and a highly stretchable stability of over 10,000 cycles under a 20% strain. Moreover, under a low irradiation energy, strain sensors with a gauge factor of 76 under a 20% strain and 5.4 under a 5% strain are fabricated. For practical demonstration, the fabricated stretchable electrode and strain sensor are attached to a human finger for detecting the motions of the finger.

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Fabrication of yolk-shell NiCo alloy@C composites derived from trimetallic metal–organic frameworks as light-weight and high-performance electromagnetic wave absorbers

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2021.106451 ◽

2021 ◽

pp. 106451

Author(s):

Ruiwen Shu ◽

Yue Wu ◽

Xiaohui Li ◽

Jiabin Zhang ◽

Zongli Wan ◽

...

Keyword(s):

Electromagnetic Wave ◽

High Performance ◽

Metal Organic Frameworks ◽

Light Weight ◽

Metal Organic

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Direct Ink Writing of Highly Conductive MXene Frames for Tunable Electromagnetic Interference Shielding and Electromagnetic Wave-Induced Thermochromism

Nano-Micro Letters ◽

10.1007/s40820-021-00665-9 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Xinyu Wu ◽

Tingxiang Tu ◽

Yang Dai ◽

Pingping Tang ◽

Yu Zhang ◽

...

Keyword(s):

Electromagnetic Wave ◽

Electromagnetic Interference ◽

High Performance ◽

Normal Operation ◽

List Type ◽

Emi Shielding ◽

Electromagnetic Interference Shielding ◽

Direct Ink Writing ◽

Aluminum Ions ◽

Wave Induced

Highlights 3D printing of MXene frames with tunable electromagnetic interference shielding efficiency is demonstrated. Highly conductive MXene frames are reinforced by cross-linking with aluminum ions. Electromagnetic wave is visualized by electromagnetic-thermochromic MXene patterns. Abstract The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interference (EMI) shielding materials to assure the normal operation of their closely assembled components. However, the most current techniques are not adequate for the fabrication of shielding materials with programmable structure and controllable shielding efficiency. Herein, we demonstrate the direct ink writing of robust and highly conductive Ti3C2Tx MXene frames with customizable structures by using MXene/AlOOH inks for tunable EMI shielding and electromagnetic wave-induced thermochromism applications. The as-printed frames are reinforced by immersing in AlCl3/HCl solution to remove the electrically insulating AlOOH nanoparticles, as well as cross-link the MXene sheets and fuse the filament interfaces with aluminum ions. After freeze-drying, the resultant robust and porous MXene frames exhibit tunable EMI shielding efficiencies in the range of 25–80 dB with the highest electrical conductivity of 5323 S m−1. Furthermore, an electromagnetic wave-induced thermochromic MXene pattern is assembled by coating and curing with thermochromic polydimethylsiloxane on a printed MXene pattern, and its color can be changed from blue to red under the high-intensity electromagnetic irradiation. This work demonstrates a direct ink printing of customizable EMI frames and patterns for tuning EMI shielding efficiency and visualizing electromagnetic waves.

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Nacre-inspired composite films with high mechanical strength constructed from MXenes and wood-inspired hydrothermal cellulose-based nanofibers for high performance flexible supercapacitors

Nanoscale ◽

10.1039/d0nr08090j ◽

2021 ◽

Vol 13 (5) ◽

pp. 3079-3091

Author(s):

Libo Chang ◽

Zhiyuan Peng ◽

Tong Zhang ◽

Chuying Yu ◽

Wenbin Zhong

Keyword(s):

Mechanical Strength ◽

High Performance ◽

Composite Films ◽

High Mechanical Strength ◽

Flexible Supercapacitor ◽

Flexible Supercapacitors

Wood-inspired HCNF@Lig introduced into MXenes constructing a nacre-like material with high mechanical strength and excellent flexibility used as a flexible supercapacitor.

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