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The electromagnetic pollution issues have been arising from the fast-growing development for electronic devices. Hence, the demand for materials with high electromagnetic interference (EMI) shielding performance has increased. Here, we developed self-healable, flexible and printable graphene oxide/silver nanowire films and textiles with excellent EMI shielding performance. The maximum electromagnetic interference shielding effectiveness (EMI SE) of 92 dB was recorded for an 18 μm-thickness film. In addition, the specific EMI shielding effectiveness was 31 dB cm3/g or 48,275 dB cm2/g when normalized to film thickness. Both values are higher than reported EMI shielding products. The composite film and coated textile were tolerant of damage induced by cracking or scratching. Damaging the films by cracking reduced the electrical conductivity, mechanical properties, and the EMI SE was decreased from 72 dB to 56 dB at 8.2 GHz. After the healing process, the EMI SE was recovered to 71 dB and mechanical properties restored. The EMI SE of textile reached a maximum of 30 dB which is suitable to use as a commercial EMI shielding product. In addition, the textile exhibited high flexibility, and showed excellent mechanical stability with no change in performance after 1000 bending cycles.

The need for thin and lightweight electromagnetic interference shielding materials is rapidly increasing in several industries, such as aerospace and telecommunication. This research finds that a shielding material, which is developed by the orthogonal pattern of spinnable multiwall carbon nanotubes (MWNTs), is ultra-light weight, thin, and has a high shielding effectiveness (SE). An orthogonal pattern, generated by just alignment of the spinnable MWNTs without adding any support materials such as polymers, ceramics, and magnets demonstrates that it is possible to efficiently attenuate electromagnetic interference (EMI) in the X-band frequency range (8.2–12.4 GHz). EMI SE in the developed shielding material is about 19.2 dB with a specific shielding effectiveness (SSE)/t (thickness) value of 73,633 dB cm2 g−1 at a thickness of about 4.48 μm. In addition, absorption effectiveness in this shielding material is as high as 96.3%, which provides excellent ability to reduce the secondary damage by reflection.

This research develops a unique material to attenuate electromagnetic interference (EMI) by using spinnable multiwalled carbon nanotubes (MWNTs) combined with bio-polydimethylsiloxane (PDMS) that contains BaTiO3 (MBPBT). In particular, a plaid pattern, formed by the spinnable MWNTs, is very effective in attenuating the propagation of EM waves,which achieves over 20 dB at 8.2–12.4 GHz (X-band frequency range). This means that a filter type of the spinnable MWNTs is actively able to handle the directionality and movement of EMI propagation. In addition, the MBPBT is characterized by its strong mechanical advantage (bending radius 180°).

A buckling structure is a crucial element for materials used in wearable electronics by taking a topographical approach to solve a spatial constraint. This review introduces various buckling structures, with the corresponding theory and fabrication, for the latest materials or devices, including secondary batteries, supercapacitors, sensors, organic thin film transistors, polymer light-emitting diodes, and organic light emitting diodes, all of which have attracted much attention recently in journals. This review demonstrates how various buckling structures can be practically integrated into functional materials to enlarge the active area, to enhance flexibility or stretchability, and to improve unique functionality itself without loss.

Functional clothing, sportswear and military uniforms, are mainly made of polyester or cotton fabrics for dealing with sweat absorption and heat transfer produced by the human body. The human body typically wears two or three garments, such as innerwear, T-shirt, and jacket, thus comprising a multilayered system. Garments’ responses to heat transfer and vapor flow differ depending on whether their physical structures are hydrophobic or hydrophilic. Hence, this study analyzes differences in heat transfer and vapor flow, induced by the human body covered with multilayered garment systems, consisting of three polyester or cotton layers. In particular, it verifies three differences in the heat transfer and relative humidity, amount of relative humidity, and response time of thermal equilibrium in multilayered systems by using a new measurement system, “H&M evaluation device”. Resultant data provide precise information regarding several differences in hydrophilic and hydrophobic multilayered fabric systems.