Thermally reducible pyroprotein-based electronic textiles (e-textiles) are fabricated using graphene oxide and a pyroprotein such as cocoon silk and spider web without any chemical agents. The electrical conductivity of the e-textile is 11.63 S cm , which is maintained even in bending, washing, and temperature variation.

Silks are protein-based natural structured materials with an unusual combination of high strength and elongation. Their unique microstructural features composed of hard β-sheet crystals aligned within a soft amorphous region lead to the robust properties of silks. Herein we report a large enhancement in the intrinsic properties of silk through the transformation of the basic building blocks into a poly-hexagonal carbon structure by a simple heat treatment with axial stretching. The carbon clusters originating from the β-sheet retain the preferred orientation along the fibre axis, resulting in a long-range-ordered graphitic structure by increasing heat-treatment temperatures and leading improvements in mechanical properties with a maximum strength and modulus up to ∼2.6 and ∼470 GPa, respectively, almost four and thirty times surpassing those of raw silk. Moreover, the formation of sp 2 carbon configurations induce a significant change in the electrical properties (e.g. an electrical conductivity up to 4.37 × 103 S cm−1).

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Effect of non-catalytic hydrogenation on the work function and charge transport properties of VO2 nanowires (NWs) was investigated.

An electronic textile-based NO 2 gas sensor was fabricated using commercial silk and graphene oxide (GO). It showed a fast response time and excellent sensing performance, which was simply accomplished by modifying the heat-treatment process. The heat treatment was conducted at 400 °C and different heating rates of 1, 3, and 5 °C/min. Compared with our previous research, the response time significantly decreased, from 32.5 to 3.26 min, and we found that the highest response was obtained with the sensor treated at a heating rate of 1 °C/min. To find the reason for this enhanced sensing performance, the morphology, structure, and chemical composition of the reduced GO (rGO) were investigated, depending on the thermal treatment process, using scanning electron microscopy, X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy. We also measured the temperature-dependent resistance of rGO, which was well described by the fluctuation-induced tunneling (FIT) model. These results revealed that the rGO thermally treated with 1 °C/ min of heating rate had the largest amount of oxygen groups. This means that the oxygen functional groups play an important role in NO 2 gas-sensing performance.

Twisted bilayer graphene (tBLG) is two stacked single graphene sheets rotated at a specific angle. The twist angle plays an important role in the physical properties of the tBLG. In this study, we analyzed the interaction distance between two graphene layers in tBLG using Raman spectroscopy and atomic force microscopy. To confirm the interaction of the upper and bottom graphenes in the tBLG, we prepared two tBLGs with twist angles of 5° and 24°. The interlayer distance was controlled by depositing a gold bar between the two graphene layers. We found that the decoupling interlayer distance of the tBLG was different depending on the twist angle (0.74 nm for 5° and 1.66 nm for 24°). This indicates that the interaction between two graphene layers is strongly coupled with small twist angle, as expected.

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