https://scholar.dgist.ac.kr/handle/20.500.11750/57018 2026-04-04T15:59:29Z https://scholar.dgist.ac.kr/handle/20.500.11750/59274 Title: MXene-Reinforced Spiral Yarns for Multimodal Triboelectric Nanogenerators and Wearable Interactive Interfaces Author(s): Cho, Soo Young; Xiong, Yao; Jiao, Haishuang; Ho, Dong Hae; Yang, Jiahong; Liu, Chao; Kim, Seonkwon; Wei, Liang; Wang, Zhong Lin; Sun, Qijun; Cho, Jeong Ho Abstract: Triboelectric nanogenerators (TENGs) have emerged as promising sustainable energy harvesters, leveraging their unique mechanoelectrical conversion capability. To optimize energy conversion efficiency, mechanical compliance, and operational stability, novel structural engineering is essential. Here, a wearable multimodal TENG system incorporating MXene-reinforced spiral yarn, fabricated via controlled MXene deposition and precise spiral winding, is demonstrated. The electronegative properties of MXene are systematically investigated through quantitative analysis of surface electrostatic potential and comprehensive evaluation of device output characteristics. The MXene-reinforced spiral yarn serves as a multifunctional electrode, enabling three distinct operational modalities of lateral sliding mode for distance measurement, internal contact-separation mode for vibration detection, and external single-electrode mode for energy harvesting. Notably, the single-electrode configuration demonstrates superior performance, capable of illuminating 104 commercial light-emitting diodes and powering electronic devices. Furthermore, the MXene-reinforced spiral yarn can be configured into a 3 x 3 crossbar-structured tactile sensor array for human-computer interaction applications. The proposed MXene-reinforced spiral yarn architecture presents substantial advancements in flexible energy harvesting systems, self-powered human-machine interfaces, and multifunctional sensory platforms. 2025-11-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/58555 Title: Getting in line: Filler alignment strategies for anisotropic composite fabrication Author(s): Ho, Dong Hae; Choi, Yoon Young; Ki, Seung Yeon; Kim, Dong-Hwan; Cho, Jeong Ho Abstract: The growing demand for high-performance materials in cutting-edge technologies has prompted intensive research into anisotropic composites, which exhibit properties that vary with direction. By aligning fillers within a matrix, it is possible to harness the distinct advantages of each filler with minimal loading, allowing for the production of lightweight, highly functional polymeric composites at a fraction of the cost of conventional engineering materials. This review examines fabrication techniques that induce anisotropy through controlled filler orientation and concentration. We categorize these methods by their principal alignment mechanisms: mechanically induced, field-induced, template-/scaffold-based, and self-assembly-driven, along with hybrid approaches. Each category offers unique benefits and faces distinct challenges in achieving targeted filler orientation and, consequently, in tuning the resultant anisotropic properties. This review also discusses the factors influencing filler alignment and how they enhance the mechanical and conductive performance of anisotropic composites. © 2025 Elsevier Ltd 2025-09-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/57443 Title: Vanishing Soft Electronics: Degradation Mechanisms of Transient Materials Author(s): Ho, Dong Hae; Cho, Jeong Ho Abstract: The rapid increase in electronic waste, coupled with the emerging demand for soft electronics, necessitates sustainable solutions. Transient soft electronics, designed to degrade after use, offer a promising pathway to address this issue. This review explores transient soft electronics from a degradation mechanism of transient dielectrics materials perspective, focusing on three primary degradation mechanisms: water-driven, organic solvent-driven, and bio-driven. The degradation processes for each mechanism will be discussed, and representative research in each area will be showcased. Additionally, the review will highlight the challenges associated with transient soft electronics in each category. © The Author(s), under exclusive licence to Korean Institute of Chemical Engineers, Seoul, Korea 2024. 2025-06-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/56987 Title: Fabric-Based Lamina Emergent MXene-Based Electrode for Electrophysiological Monitoring Author(s): Lee, Sanghyun; Ho, Dong Hae; Jekal, Janghwan; Cho, Soo Young; Choi, Young Jin; Oh, Saehyuck; Choi, Yoon Young; Lee, Taeyoon; Jang, Kyung-In; Cho, Jeong Ho Abstract: Commercial wearable biosignal sensing technologies encounter challenges associated with irritation or discomfort caused by unwanted objects in direct contact with the skin, which can discourage the widespread adoption of wearable devices. To address this issue, we propose a fabric-based lamina emergent MXene-based electrode, a lightweight and flexible shape-morphing wearable bioelectrode. This work offers an innovative approach to biosignal sensing by harnessing the high electrical conductivity and low skin-to-electrode contact impedance of MXene-based dry electrodes. Its design, inspired by Nesler's pneumatic interference actuator, ensures stable skin-to-electrode contact, enabling robust biosignal detection in diverse situations. Extensive research is conducted on key design parameters, such as the width and number of multiple semicircular legs, the radius of the anchoring frame, and pneumatic pressure, to accommodate a wide range of applications. Furthermore, a real-time wireless electrophysiological monitoring system has been developed, with a signal-to-noise ratio and accuracy comparable to those of commercial bioelectrodes. This work excels in recognizing various hand gestures through a convolutional neural network, ultimately introducing a shape-morphing electrode that provides reliable, high-performance biosignal sensing for dynamic users. © 2024. The Author(s). 2024-09-30T15:00:00Z