Carbon fiber/thermoelectric Ag2S core-shell structure based temperature-pressure dual-mode sensors

Temperature plays a pivotal role in the environment, directly affecting the survival, function, and overall health of organisms by shaping their physiological and behavioral responses. Likewise, pressure is an essential physical parameter, ranging from cosmic phenomena to complex biological processes within the human body. Both factors serve as critical indicators in health assessment, offering valuable data on functions such as breathing patterns, joint dynamics, and other vital activities. As a result, the development of dual-mode sensors capable of detecting both temperature and pressure simultaneously has garnered significant attention. These advanced sensors hold immense potential in areas such as medical care, rehabilitation, human-computer interaction, and flexible robotics.

Recently, a team by Peng-An Zong from the School of Materials Science and Engineering at Nanjing Tech University in China recently developed a dual-mode temperature-pressure sensor based on a core-shell carbon fiber/Ag₂S film fabricated using a facile electrodeposition. The electromagnetic interference shielding effectiveness (EMI SE) of the composite film was also significantly improved. Additionally, the CC/Ag₂S film has enhanced mechanical properties, excellent antibacterial properties and moisture permeability.

The team published their work in Journal of Advanced Ceramics on April 4, 2025.

“In this report, we made a dual-mode temperature-pressure sensor based on a core-shell carbon fiber/Ag₂S film fabricated using a facile electrodeposition. The sensor employed its thermoelectric mechanism for self-powered temperature sensing, enabling accurate detection of finger touches and respiratory states, and exhibited a rapid response time of 0.7 s. For pressure sensing, its shell-to-shell contact ensured an ultra-fast response time of 0.2 s, facilitating the precise monitoring of body movements. Beyond its sensing functionalities, the sensor demonstrated superior electromagnetic interference shielding efficiency of 50 dB (a twofold improvement), tensile strength of 59 MPa (10× enhancement), and antibacterial effectiveness over 95%,” said Peng-an Zong, professor from the School of Materials Science and Engineering at Nanjing Tech University (China).

“The tactile sensor, composed of multiple TE legs, generates distinct voltage signals depending on the number of fingers in contact, which with a rapid response time of ~0.7 s and a recovery time of 2.1 s. Many words can be generated through different finger arrangements. This self-powered tactile sensor holds promising potential for assisting individuals with language barriers in the future,” said Peng-an Zong.

“The sensor is integrated into a mask for respiration sensing, with one end inside as the hot side, contacting exhaled air, and the other outside as the cold side, exposed to ambient air. The temperature difference from exhaled air generates a voltage signal. The respiration sensor can monitor respiratory rate changes during activities like standing, squatting, and sitting,” said Peng-an Zong.

“Based on the excellent flexibility of the film and its well-formed three-dimensional conductive network, the resistance changes during the bending process. A pressure sensor composed of a single film is designed to monitor these changes. The sensor can detect mechanical deformation of different amplitudes within the pressure range, such as those of the elbow, wrist, knee and finger, each producing a distinct signal,” said Peng-an Zong.

“The CC/Ag₂S deposited at −0.6 V shows the highest SE_T of 50.1 dB, more than twice that of the original CC (23.6 dB). The tensile stress of pure CC is 5.1 MPa, while the tensile stress of CC/Ag₂S increases tenfold, reaching 59.3 MPa. In addition, CC/Ag₂S film has an antibacterial rate of 95.04% and excellent water vapor permeability (2987 g m⁻² d⁻¹),” said Peng-an Zong.

Other contributors include Junjie Zhu, Size Lou, Min Shu, Miao Liu from the college of Materials Science and Engineering, Nanjing Tech University; Yuan Wang, Heng Liu from Advanced Institute for Materials Research (WPI-AIMR), Tohohu University; Chunlei Wan from State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University.

This work was supported by NSAF (no. U2230131) and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

About Author

Dr. Peng-an Zong serves as an Associate Professor at the School of Materials Science and Engineering, Nanjing Tech University. He obtained his Ph.D. degree from the Shanghai Institute of Ceramics, Chinese Academy of Sciences, in 2016. Following this, he held a postdoctoral position at Tsinghua University from 2016 to 2019. Dr. Zong’s research expertise encompasses semiconductor thermoelectric materials and devices, micro/nano, and flexible manufacturing techniques, alongside their diverse applications in specialized energy systems, thermal management solutions, and sensor technologies.

About Journal of Advanced Ceramics

Journal of Advanced Ceramics (JAC) is an international academic journal that presents the state-of-the-art results of theoretical and experimental studies on the processing, structure, and properties of advanced ceramics and ceramic-based composites. JAC is Fully Open Access, monthly published by Tsinghua University Press, and exclusively available via SciOpen. JAC’s 2023 IF is 18.6, ranking in Top 1 (1/31, Q1) among all journals in “Materials Science, Ceramics” category, and its 2023 CiteScore is 21.0 (top 5%) in Scopus database. ResearchGate homepage: https://www.researchgate.net/journal/Journal-of-Advanced-Ceramics-2227-8508