In order to generate the soft bending motion driven by pressure change in hydrogen gas, a soft device was made up and tested. In former research, a unimorph structure was proposed, in which a silicone rubber with LaNi 5 alloy powder distributed was piled up on a pure silicone rubber sheet. Using this structure we succeeded a bending motion of the soft device by applying hydrogen gas pressure. However the mechanical response was slow. To improve the active motion, a catalyst of Pd-Al 2 O 3 powder was mixed into the hydrogen storage alloy powder in the rubber. By simple addition of catalyst powder before dispersion into the rubber, we obtained drastically modified responses and displacement in the movement of the device. The catalyst probably accelerated dissociation of hydrogen molecule on the surface of hydrogen storage material particle.

Anodization in HO(CH 2 CH 2 O) n H (1a, n‫;2؍‬ 1b, n‫;3؍‬ 1c, n‫)4؍‬ as an initial derivatization tool for preparing glassy carbon (GC) electrodes covalently modified with amino compounds was explored. As an amino compound to be immobilized, 4-amino-2,2,6,6-tetramethylpiperidinyl-1-oxyl (4-amino-TEMPO) was selected. When GC electrodes anodized at 2.0 V vs. Ag wire coated with AgCl in 1 containing RCH 2 CH 2 SO 3 Na (2a, R‫؍‬H; 2b, R‫؍‬OH) were treated with a N,N-dimethylformamide (DMF) or CH 2 Cl 2 solution of 4-amino-TEMPO and 1,3-dicyclohexylcarbodiimide (DCC), TEMPO-modified GC electrodes were afforded. Coverage (G G TEMPO ) of the electrode surfaces by TEMPO was estimated by cyclic voltammetry in CH 3 CN containing NaClO 4 . A TEMPO-modified GC electrode with the best G G TEMPO (1.36؋10 ؊10 mol/cm 2 ) was obtained by anodization in 1b containing 2a at the expense of 3.0 C followed by amidization in DMF for 7 d. On cyclic voltammetry, the TEMPO-modified GC electrode showed good and stable electrocatalytic ability for oxidation of allyl alcohol in the presence of 2,6-lutidine.

A soft actuator with a giant bending motion controlled by hydrogen pressure for artificial muscles has been innovated. It resembles a bimetal and is constructed with soft silicone rubber sheets for driving and supporting. The LaNi5 hydrogen storage alloy powder is dispersed in the driving sheet. The reversible motion is observed and operated by hydrogenation and degassing. The giant bending motion of over 4000 ppm of strain was observed from 2 min to 3 h of hydrogenation time. The actuator developed shows a giant bending motion as large as that of a typical shape memory alloy.

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A mechanical mover with hydrogen storage alloy was made up and tested. In former research, a unimorph structure was proposed, in which a silicone rubber with LaNi 5 alloy powder distributed was piled up on a pure silicone rubber sheet. Using this structure we succeeded a soft movement of the device by applying hydrogen gas pressure. Because the movement indicated slow response, therefore in this research, we tried to improve the response of the moving device by mixing a catalyst of Pd Al 2 O 3 powder into the hydrogen storage alloy powder in the rubber. We obtained drastically improved responses in a movement of the device.