As wearable electronics and electronic skin technologies rapidly advance, the importance of conductive materials that operate reliably under multidirectional stretching and deformation has grown. However, conventional conductive films have been limited by structural characteristics that cause variation in electrical performance depending on the deformation direction.

A study that overcomes these limitations was reported as a global collaborative research project by Professor Tae‑wook Kim of Jeonbuk National University (JBNU), Professor Dae‑hyung Kim's team at Seoul National University, and the University of Illinois at Urbana–Champaign (UIUC), attracting attention in the academic community.

The research team reported that they succeeded in realizing a conductive material that maintains stable electrical performance even under stretching and bending.

The study was published in the latest issue of the world‑leading materials science journal Advanced Materials (IF=26.8, JCR top 2.1%). In recognition of its innovation and completeness, it was selected as a Front Cover article.

The research included JBNU PhD candidate Seung‑yeon Kim as well as Seoul National University integrated MS‑PhD students Min‑jeong Kim and Son‑woo Jeong, and UIUC postdoctoral researcher Moon‑ki Choi as co‑first authors. Professors Tae‑wook Kim and Dae‑hyung Kim and postdoctoral researcher Qingchang Liu participated as corresponding authors.

The team identified the root cause of the existing problem in the contact mode of nanostructures and proposed a new assembled architecture based on two‑dimensional silver nanosheets (Ag nanosheets) to address it. In particular, they induced face‑to‑face contact between nanosheets to maximize contact area, designing the system so that electrical connections remain stable even when mechanical deformation occurs.

As a result, they achieved both a high conductivity of approximately 115,000 S/cm and stretchability exceeding 50%. They also succeeded in implementing a conductive film that exhibits uniform electrical properties regardless of direction, even in an ultrathin structure of approximately 235 nm.

Using coarse‑grained molecular dynamics (CGMD) simulations, the team elucidated the mechanism of nanosheet arrangement and overlap formation and provided a theoretical basis for material design. Furthermore, by fabricating an ultrathin electronic skin using the developed material, they confirmed its potential application as a tactile sensor capable of pressure sensing and position recognition.

Professor Tae‑wook Kim explained, "This is a technological achievement that realizes electronic devices that operate stably under deformation by precisely controlling the assembly of two‑dimensional nanosheets," adding, "The study demonstrates the potential of two‑dimensional metallic nanomaterials as key materials for next‑generation flexible electronic devices."

Meanwhile, this research was supported by the Institute for Basic Science (IBS, IBS‑R006‑A1), the Ministry of Science and ICT and the National Research Foundation of Korea (NRF), the Air Force Office of Scientific Research (AFOSR) MURI, and the U.S. National Science Foundation (NSF) MRSEC program.