A Photoactivated Artificial Muscle Model Unit: Reversible, Photoinduced Sliding of Nanosheets Yu Nabetani,† Hazuki Takamura,† Yuika Hayasaka,† Tetsuya Shimada,† Shinsuke Takagi,† Hiroshi Tachibana,† Dai Masui,† Zhiwei Tong,‡ and Haruo Inoue*,† †Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1 Minami-ohsawa, Hachioji, Tokyo 192-0397, Japan, and SORST, Japan Science and Technology (JST) ‡Department of Chemical Engineering, Huaihai Institute of Technology, Lianyungang 222005, People’s Republic of China

Introduction Morphological changes of organic single crystal and polymer films Surface relief grating Light-driven actuator

Morphological Change of layered Hybrid Film Thickness ～450 nm The number of layers ～84 18 nm ～1500 nm

Structure of Layered Hybrid Film C3F-azo

Changes in the Absorption Spectra of C3F-azo UV(λuv = 368 nm, 1.9 mW/cm2) VIS(λvis = 463 nm, 0.65 mW/cm2) 20 min 2 min

Reversible Sliding of film Top view of the layered hybrid film Glass substrate

Height Profile of Layered Hybrid Film

Variation of Height

Mechanism of Shrinkage, Expansion, and Sliding d020 = 5.35 nm Thickness of nanosheet = 1.23 nm Interlayer space = 4.12 nm 43°

Conclusion The cooperative photoisomerization reactions in the interlayer spaces induce 3D morphological change(each nanosheet sliding and interlayer shrinkage and expansion). Detailed mechanism of the 3D change is not yet fully understood.

Synthesis of C3F-azo ＋ product product ＋ C3F-azo