Organic Electronics Laboratory
Staff & Contact
| Educational Staff | Prof. Masakazu Nakamura Associate Prof. Hiroaki Benten Assistant Prof. Ryota Fukuzaw Adjunct Prof. Masahiro Hiramotoa Adjunct Assistant Prof. Pandey Manish |
|---|---|
| URL | https://mswebs.naist.jp/LABs/greendevice/www/index_e.html |
Education and Research Activities in the Laboratory
Let’s imagine rollable electronic equipment, a piece of fabric generating electricity by body heat, or a paper-like solar cell. We are pursuing the realization of such novel electronic devices through studies elucidating unique phenomena in organic solids and applying the findings to the device functions using knowledge of solid-state physics, electronics, surface science, polymer physics, and molecular science. Our laboratory utilizes unique approaches made possible by our original characterization tools. We determine individual research projects ranging from basic science to the development of real devices, depending on the student’s interests and aptitudes. We foster independent thinking and a top-level mindset through collaborative research with institutes in Japan and overseas. Thus, we aim to cultivate researchers with a broad knowledge of science and a keen interest in industrial applications.Research Themes
Three major ongoing projects are presented here, but other collaborations are underway on a spot basis.1. Control of Charge/Heat Transports by Molecular Junctions for Wearable Thermoelectric Generators
We have demonstrated that the thermal conductivity of a carbon nanotube (CNT) composite significantly decreases by forming molecular junctions between nanotubes with a specially designed protein and other molecules. The unique character of CNT allows us to fabricate its composite yarn. With such a novel flexible thermoelectric material, we are aiming at the fabrication of “thermoelectric cloths,” which can be handled like normal cloths but generate electricity from body heat.
2. Basic and Applied Research on the “Giant Seebeck Effect”
We are also trying to elucidate and control the Giant Seebeck Effect in organic semiconductors discovered by us. The conventional theory of the Seebeck effect takes only the charge transport within the band theory. However, in organic semiconductors, charge and molecular vibration are strongly coupled, and thereby, the Seebeck coefficient sometimes appears to be up to 100 times larger. Not only the scientific studies, we are also developing a way to utilize this new phenomenon to produce innovative thermoelectric generators.
3. Development of Next-Generation Plastic Solar Cells
We develop next-generation “plastic” solar cells based on p- and n-type semiconducting polymers. We have been attempting to elucidate the photovoltaic properties governed by the nanoscale phase separation of polymers and the transport/recombination dynamics of photogenerated carriers with photoconductive atomic force microscopy and other techniques. Through understanding the nano-scale electronic functions, we propose new device structures that can maximize the performance.
Recent Research Papers and Achievements
- M. Ito, et al., “From materials to device design of a thermoelectric fabric for wearable energy harvesters”, J. Mater. Chem. A 5, 12068 (2017).
- H. Kojima et al., “Universality of giant Seebeck effect in organic small molecules”, Mater. Chem. Front. 2, 1276 (2018).
- H. Benten et al., “Chain Aggregation Dictates Bimolecular Charge Recombination and Fill Factor of All-Polymer Blend Solar Cells” J. Mater. Chem. A 10, 21727 (2022).
- H. Benten et al., “Nanoscale Observation of the Influence of Solvent Additives on All-Polymer Blend Solar Cells by Photoconductive Atomic Force Microscopy” ACS Appl. Polym. Mater., 4, 169 (2022).
- M. Pandey et al., “Recent Advances in Orientation of Conjugated Polymers for Organic Field-Effect Transistors” J. Mater. Chem. C 7, 13323 (2019).
- M. Pandey et al., “Unidirectionally aligned donor-acceptor semiconducting polymers in floating films for high-performance unipolar n-channel organic transistors”, Adv. Electron. Mater., 9, 2201043 (2023).
- M. Suda et al., “Light-driven molecular switch for reconfigurable spin filters”, Nat. Commun. 10, 2455 (2019).