学生のSUWANSOONTORN, Athchayaさん（博士後期課程3年、物質化学領域、長尾研究室）による、公益社団法人電気化学会刊行のElectrochemistry 誌に掲載された論文 "Interfacial and Internal Proton Conduction of Weak-acid Functionalized Styrene-based Copolymer with Various Carboxylic Acid Concentrations" が、2021年5・6月の間に同誌に掲載された論文の中で、最も多くダウンロードされた論文として選出されました。
　この論文で発表した研究成果については、令和3年5月28日に本学から「高分子薄膜における水素イオンの界面輸送で新知見」としてプレスリリースしています。

　電気化学会は、電気化学の基礎と応用に関する研究の推進と、それを基礎とする産業技術の進歩を図り、学術文化の進展と社会の発展に寄与することを目的として、1933年に設立されました。

■受賞年月日
　令和3年7月20日

■選出された論文のタイトル
Interfacial and Internal Proton Conduction of Weak-acid Functionalized Styrene-based Copolymer with Various Carboxylic Acid Concentrations

■著者
Athchaya Suwansoontorn, Katsuhiro Yamamoto, Shusaku Nagano, Jun Matsui, Yuki Nagao

■対象となった研究の内容
Investigation of interfacial proton transport is necessary to elucidate biological systems. As commonly found in biomaterials, the carboxylic acid group was proven to act as a proton conducting group. This study investigated the influence of carboxylic acid concentration on both interfacial and internal proton transport. Several styrene-based polymers containing the carboxylic acid group were synthesized. The amount of carboxylic acid group in the polymer chain was varied to explore the effects of weak acid concentration on polymer thin films' electrical properties. The IR p-polarized multiple-angle incidence resolution spectrometry (pMAIR) spectra show the higher ratio of the free carboxylic acid groups rather than cyclic dimers in polymers with a higher concentration of carboxylic acid group, facilitating the more hydrogen bonding networks in films. The water uptake results reveal the similar number of adsorbed water molecules per carboxylic acid group in all thin films. Remarkably, polymer thin films with high carboxylic acid concentration provide internal proton conduction because of the relative increase in the amount of the free carboxylic acid group. In contrast, interfacial proton conduction was found in low carboxylic acid concentration polymers because of the relatively large amount of cyclic dimer carboxylic acid group and poor amount of free carboxylic acid group. This study provides insight into interfacial proton transport behavior according to the weak acid concentration, which might explain proton transport in biological systems.

■選出にあたって一言
We are greatly honored to receive the award for Most Downloaded Papers for "Electrochemistry". First, I want to express my appreciation to Assoc. Prof. Katsuhiro Yamamoto, Prof. Shusaku Nagano, Prof. Jun Matsui, and Assoc. Prof. Yuki Nagao for their valuable comments and guidance. And I am also grateful to Nagao LAB members for their support. We expect that our research can contribute to developing bio-conductive materials for eco-friendly devices.

令和3年7月27日