2025.02.25
News
”Non-destructive image sensor goes beyond bulkiness” Freely coatable & paintable design on functional photo-thermal module
Chuo University
Summary
Led by Assistant Prof. Kou Li, a research group in Chuo University, Japan, has developed an all-printable device fabrication strategy to resolve the existing technical limitations of multi-functional image sensor sheets for non-destructive inspections, with a recent paper publication in Small Science.
Grapical abstract
While photo-thermoelectric (PTE) sensors are potentially suitable for testing applications, such as non-destructive material-identification in ultrabroad millimeter-wave (MMW)–infrared (IR) bands, their device designs have primarily employed a single material as the channel. In general, PTE sensors combine photo-induced heating with associated thermoelectric (TE) conversion, and the employment of a single material channel regulates the utilization of devices by missing the opportunity for fully utilizing their fundamental parameters. Here, long-standing technical difficulties in the PTE sensor design field induce such crucial situations, where typical constituent materials exhibit trade-off trends between photo-absorptance values (for heating) and the Seebeck coefficients (for TE conversion).
To this end, this manuscript made the following significant contributions.
- Developing the PTE sensor structure in an effective hybrid combination between bismuth composite (Bicom) TE electrodes (Seebeck coefficient > 100 µV/K) and highly efficient carbon nanotube (CNT) film photo-thermal absorber channels.
- Performing photo-detection operations by the sensor with over ten-fold response intensities than those of single-material PTE detectors (typically: pn-junction CNT films) as making the most of the above advantageous hybrid strategy, satisfying the readable signal range criteria (> several millivolts) for the device coupling with portable circuit modules.
- Designing the hybrid PTE sensor into all-solution-processable fabrication configurations by effectively arranging Bicom powders with conductive solvents and surfactants as paste-like stable TE converting electrodes, along the inherently ink-formed CNT film absorber.
- Achieving ultrabroad MMW–IR operations with the hybrid paste PTE device over typical wideband detectors in comparable sensitivities (minimum noise equivalent power: 560 fWHz−1/2) to existing narrowband sensors, while simultaneously maintaining optical stabilities against severe environmental conditions (e.g., high-temperatures and cyclic deformations).
- Demonstrating functional non-destructive imaging inspections at high-usability with the hybrid PTE sensor based on the advantages above optical features and paste-unique freely paintable device setups, such as omni-directional observations of a 3D target without blin-spot by fabricating an easy-to-handle panoramic bowl camera module.
The paper was published online in the international scientific journal, Small Science (February 20, 2025).
-Researcher-
| Kou Li |
Assistant Professor Faculty of Science and Engineering, Chuo University |
(Department of Electrical, Electronic, and Communication Engineering) |
| Yuto Matsuzaki |
Master course student Graduate School of Science and Engineering, Chuo University |
(Department of Electrical, Electronic, and Communication Engineering) |
| Yukio Kawano |
Professor Faculty of Science and Engineering, Chuo University |
(Department of Electrical, Electronic, and Communication Engineering) |
| Reiji Tadenuma |
Bachelor student* *at the time of research Faculty of Science and Engineering, Chuo University |
(Department of Electrical, Electronic, and Communication Engineering) |
| Yuto Aoshima |
Bachelor student* *at the time of research Faculty of Science and Engineering, Chuo University |
(Department of Electrical, Electronic, and Communication Engineering) |
-Paper Information-
| Journal | Small Science |
| Title | All-solution-processable hybrid photo-thermoelectric sensors with carbon nanotube absorbers and bismuth composite electrodes for non-destructive testing |
| Author |
Yuto Matsuzaki†,1, Reiji Tadenuma†,1, Yuto Aoshima†,1, Minami Yamamoto1, Leo Takai1, Yukito Kon1, Daiki Sakai1, †Co-first author *Corresponding authorK.L., Y.M., and Y.Ka. conceptualized this work and coordinated the experiments. Y.M. and K.L. wrote the manuscript. Y.M., R.T., Y.A., M.Y., L.T., Y.Ko., D.Sa., N.T., R.K., Q.Z., N.H., M.S., D.Sh., R.O., S.H., and K.L. performed the experiments. |
| Affiliation |
1 Department of Electrical, Electronic, and Communication Engineering, Faculty of Science and Engineering, 2 Laboratory for Future Interdisciplinary Research of Science and Technology, Tokyo Institute of Technology 4 National Institute of Informatics 5 Kanagawa Industrial Institute of Science and Technology |
| DOI | 10.1002/smsc.202400448 |
-Acknowledgement-
The authors acknowledge NOF Co. for providing surfactants. The authors also thank Zeon Co. for providing CNT solutions. This work was financially supported by a part of ACT-X (JPMJAX23KL) and Mirai Program (JPMJMI23G1): JST, KAKENHI (JP22H01553, JP22H01555, JP23H00169, JP23K19125, JP24K01288, and JP24K17325): JSPS, and grants (Murata Science Foundation, Matsuo Foundation, Sumitomo Electric Groups CSR Foundation, Takano Science Foundation, Thermal & Electric Energy Technology Foundation, Precise Measurement Technology Promotion Foundation, Suzuki Foundation, Iwatani Naoji Foundation, Futaba Foundation, Konica Minolta Science and Technology Foundation, Fuji Seal Foundation, Telecommunications Advancement Foundation, TEPCO Memorial Foundation, Paloma CSR Foundation, Takano Life Science Research Foundation, The Foundation for The Promotion of Ion Engineering, Hattori Hokokai Foundation, Mechanical Social Systems Foundation, and Kanagawa Institute of Industrial Science and Technology).
(Research content)
Kou Li
Assistant Professor
Department of Electrical, Electronic, and Communication Engineering,
Faculty of Science and Engineering,
Chuo University
TEL: +81-3-3817-1860
E-mail: li▲elect.chuo-u.ac.jp
* Please replace ▲ with @ when sending an email.
Research Promotion Office,
Chuo University
E-mail: kkouhou-grp▲g.chuo-u.ac.jp
* Please replace ▲ with @ when sending an email.
