Improving Electro-Mechano-Chemical Performance of Alginate Hydrogel Artificial Muscles Through Micro-Nano Doping

Area of Science:

• Materials Science
• Biomaterials Engineering
• Chemical Actuators

Background:

• Alginate hydrogel artificial muscles (AHAMs) show promise as electrically responsive actuators for flexible and biological applications.
• Current AHAMs suffer from low response actuation and limited operating life, hindering their practical use.
• Improving electro-mechano-chemical performance is crucial for advancing AHAM technology.

Purpose of the Study:

• To enhance the performance of alginate hydrogel artificial muscles (AHAMs) by incorporating micro-nanomaterials.
• To investigate the effects of doping with carboxylated multi-walled carbon nanotubes (c-MWCNTs) and graphene oxide (GO) on AHAM properties.
• To improve electrical conductivity, response actuation, and mechanical stability of AHAMs.

Main Methods:

• Covalent bonding of c-MWCNTs to sodium alginate (SA) via esterification to enhance conductivity.
• Incorporation of graphene oxide (GO) to create a compact structure, improve dispersion, and enhance ion channel stability.
• Utilizing polystyrene sulfonate sodium (PSS) to improve water retention and reduce the elastic modulus of the hydrogel.

Main Results:

• Doping with c-MWCNTs and GO significantly enhanced electrical conductivity and response actuation.
• Reduced hydrogel resistance by 36.8% due to improved ion channel stability from GO.
• Achieved a 52.3% decrease in elastic modulus and a 5.9-fold increase in the maximum actuated force-mass ratio compared to the control group.

Conclusions:

• Doping alginate hydrogels with c-MWCNTs and GO effectively improves the electro-mechano-chemical performance of AHAMs.
• The modified AHAMs exhibit enhanced actuation force and stability, addressing limitations of previous designs.
• These findings pave the way for developing more efficient and durable artificial muscles for diverse applications.