TY - JOUR
T1 - Electroosmosis-Driven Hydrogel Actuators Using Hydrophobic/Hydrophilic Layer-By-Layer Assembly-Induced Crack Electrodes
AU - Ko, Jongkuk
AU - Kim, Dongjin
AU - Song, Yongkwon
AU - Lee, Seokmin
AU - Kwon, Minseong
AU - Han, Seungyong
AU - Kang, Daeshik
AU - Kim, Yongju
AU - Huh, June
AU - Koh, Je Sung
AU - Cho, Jinhan
N1 - Funding Information:
This work was supported by a National Research Foundation (NRF) funded by the Ministry of Education of Korea (2019R1A4A1027627; 2018R1A2A1A05019452; 2019R1F1A1063066) and the new faculty research fund of Ajou University and the Ajou University research fund.
Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/9/22
Y1 - 2020/9/22
N2 - Development of soft actuators with higher performance and more versatile controllability has been strongly required for further innovative advancement of various soft applications. Among various soft actuators, electrochemical actuators have attracted much attention due to their lightweight, simple device configuration, and facile low-voltage control. However, the reported performances have not been satisfactory because their working mechanism depends on the limited electrode expansion by conventional electrochemical reactions. Herein, we report an electroosmosis-driven hydrogel actuator with a fully soft monolithic structure-based whole-body actuation mechanism using an amphiphilic interaction-induced layer-by-layer assembly. For this study, cracked electrodes with interconnected metal nanoparticles are prepared on hydrogels through layer-by-layer assembly and shape transformation of metal nanoparticles at hydrophobic/hydrophilic solvent interfaces. Electroosmotic pumping by cracked electrodes instantaneously induces hydrogel swelling through reversible and substantial hydraulic flow. The resultant actuator exhibits actuation strain of higher than 20% and energy density of 1.06 × 105 J m-3, allowing various geometries (e.g., curved-planar and square-pillared structures) and motions (e.g., slow-relaxation, spring-out, and two degree of freedom bending). In particular, the energy density of our actuators shows about 10-fold improvement than those of skeletal muscle, electrochemical actuators, and various stimuli-responsive hydrogel actuators reported to date.
AB - Development of soft actuators with higher performance and more versatile controllability has been strongly required for further innovative advancement of various soft applications. Among various soft actuators, electrochemical actuators have attracted much attention due to their lightweight, simple device configuration, and facile low-voltage control. However, the reported performances have not been satisfactory because their working mechanism depends on the limited electrode expansion by conventional electrochemical reactions. Herein, we report an electroosmosis-driven hydrogel actuator with a fully soft monolithic structure-based whole-body actuation mechanism using an amphiphilic interaction-induced layer-by-layer assembly. For this study, cracked electrodes with interconnected metal nanoparticles are prepared on hydrogels through layer-by-layer assembly and shape transformation of metal nanoparticles at hydrophobic/hydrophilic solvent interfaces. Electroosmotic pumping by cracked electrodes instantaneously induces hydrogel swelling through reversible and substantial hydraulic flow. The resultant actuator exhibits actuation strain of higher than 20% and energy density of 1.06 × 105 J m-3, allowing various geometries (e.g., curved-planar and square-pillared structures) and motions (e.g., slow-relaxation, spring-out, and two degree of freedom bending). In particular, the energy density of our actuators shows about 10-fold improvement than those of skeletal muscle, electrochemical actuators, and various stimuli-responsive hydrogel actuators reported to date.
KW - crack electrode
KW - electroosmosis-driven hydrogel actuator
KW - hydrophobic/hydrophilic layer-by-layer assembly
KW - metal nanoparticle
KW - swelling/deswelling
UR - http://www.scopus.com/inward/record.url?scp=85091554154&partnerID=8YFLogxK
U2 - 10.1021/acsnano.0c04899
DO - 10.1021/acsnano.0c04899
M3 - Article
C2 - 32885947
AN - SCOPUS:85091554154
VL - 14
SP - 11906
EP - 11918
JO - ACS Nano
JF - ACS Nano
SN - 1936-0851
IS - 9
ER -