Plasmonic‐Assisted Graphene Oxide Films with Enhanced Photothermal Actuation for Soft Robots

Abstract

Carbon‐based materials are widely used as light‐driven soft actuators relying on their thermal desorption or expansion. However, applying a passive layer in such film construction greatly limits the actuating efficiency, e.g., bending amplitude and speed. In this work, a dual active layer strengthened bilayer composite film made of graphene oxide (GO)–polydopamine (PDA)–gold nanoparticles (Au NPs)/polydimethylsiloxane (PDMS) is developed. In this film, the conventional passive layer is replaced by another AuNPs‐enhanced thermal responsive layer. When applying NIR light exposure, the whole film deforms controllably resulting from the water loss in the GO–PDA–Au NPs layer and thermal expansion in the PDMS layer. Benefiting from the dual active bilayer mechanism, the thin film's actuating efficiency is dramatically improved compared with that of conventional methods. Specifically, the bending amplitude is enhanced up to 173%, and the actuating speed is improved to 3.5‐fold. The soft actuator can act as an artificial arm with high actuating strength and can be used as a wireless gripper. Moreover, the film can be designed as soft robots with various locomotion modes including linear, rolling, and steering motions. The developed composite film offers new opportunities for biomimetic soft robotics as well as future applications.

Light‐Driven Self‐Oscillating Actuators with Phototactic Locomotion Based on Black Phosphorus Heterostructure

“…[7] Among various type of actuators,photoactuator owns unique features of remote actuation, no contact, concise control, and abundant sources of light energy,which is suitable as driving unit for use in untethered soft robot. [8] Fort he purpose of fabricating high-performance photoactuator,i ti sc rucial to develop new light responsive materials.I nr ecent years,t wo dimensional (2D) nanomaterials such as graphene, [9] MXene [10] and MoS 2 [11] with unique structure and excellent optical properties have been used to prepare photoactuators with outstanding actuation performance,r evealing the great potential of the new 2D materials in the next-generation highperformance photoactuators.Black phosphorus (BP) is anew class of 2D nanomaterials with unique lamellar structure, excellent properties and promising applications in energy storage, [12] catalysis, [13] sensing, [14] and biomedicine. [15] In particular,B Ph as shown anisotropic mechanical property, [16] exceptional electromechanical performance, [17] outstanding photothermal conversion capability across ab road range of wavelengths, [18] and thermal expansion feature, [19] making it ideal candidate for the fabrication of soft actuators.F or example,W ue tal.,f abricated black phosphorus based electrochemical actuator with high actuation properties, which mainly stems from the ordered lamellar structure and large redox activity of the black phosphorus for ions with smooth diffusion and flooding accommodation.…”

Plasmonic Nanostructures for Photothermal Conversion

“…[ 77 ] To convert photon energy to mechanical deformations, photoactive agents, such as photothermal materials (e.g., nanoparticles or organic dyes) and photochemical switches (e.g., azobenzene‐based molecules), are needed. Photons emitted by a light source and absorbed by a photoactive agent may produce mechanical motions by 1) photothermal expansion; [ 78,79 ] 2) conformational change; [ 80,81 ] or 3) phase transition (e.g., glass transition of shape‐memory materials, [ 82,83 ] nematic‐isotropic transition of liquid crystals, [ 84,85 ] and hydrophilic–hydrophobic transition of hydrogels. [ 86,87 ] )…”

Strategic Advances in Spatiotemporal Control of Bioinspired Phenolic Chemistries in Materials Science

“…[49] Besides the intrinsic affinity to various metal ions, the mild reducing capability of PDA toward noble metal ions favors the in situ nucleation and growth of metallic nanomaterials, a process that is known otherwise as electroless metallization. We have currently developed four types of PDA-metal hybrid materials with varying compositions and properties, namely, PDA-M n+ , [247] PDA-M, [248] and PDA-M x O y [88] /PDA-M x S y [249] and PDA-MOF. [250][251] These hybrids, with strong coordination between PDA and metals, can have greater stability and functionality for applications in energy, catalysis, and others.…”