Molecularly Engineered Hydrogel Electrolyte Embedded with Multifunctional Oxygen-Rich Macrocyclic Units for Uniform...

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• Zinc-ion batteries (ZIBs) face challenges with anode stability and dendrite formation.
• Existing hydrogel electrolytes often lack sufficient mechanical strength and ion transport capabilities.
• Simple polymer combinations are insufficient for advanced ZIB electrolyte design.

Purpose of the Study:

• To design and synthesize a novel multifunctional monomer, benzo-15-crown-5-acrylamide (BCAm), for hydrogel electrolytes.
• To create a robust hydrogel electrolyte (PBCM-HE) that regulates the zinc ion solvation structure.
• To enhance the electrochemical performance and interfacial stability of ZIBs.

Main Methods:

• One-step polymerization to synthesize the PBCM-HE hydrogel electrolyte.
• Incorporation of BCAm monomer with supramolecular macrocyclic units into the hydrogel network.
• Characterization of mechanical properties (tensile and compressive strength) and ionic conductivity.
• Electrochemical testing of Zn||PBCM-HE||MnO2 full cells.

Main Results:

• PBCM-HE exhibits excellent mechanical properties (105 kPa tensile, 0.6 MPa compressive strength).
• The hydrogel shows high ionic conductivity (61.7 mS cm-1) and a remarkable transference number (0.86).
• Full cells achieve a high discharge specific capacity of 290.9 mAh g-1 at 0.1 C with uniform zinc deposition.

Conclusions:

• The multifunctional monomer BCAm effectively regulates zinc ion solvation and stabilizes the anode interface.
• The developed PBCM-HE hydrogel electrolyte offers superior mechanical and electrochemical performance for ZIBs.
• This work provides new strategies for designing advanced hydrogel electrolytes for high-performance zinc-based energy storage devices.