A Bioinspired Gradient Hydrogel Electrolyte Network with Optimized Interfacial Chemistry toward Robust Aqueous...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Hydrogel electrolytes offer promise for aqueous zinc-ion batteries (ZIBs).
• Challenges remain in balancing reaction kinetics and zinc deposition stability.
• Existing hydrogels struggle to meet the demands of high-performance ZIBs.

Purpose of the Study:

• To develop a gradient-networked hydrogel electrolyte for improved ZIB performance.
• To address the limitations of current hydrogel electrolytes in ZIBs.
• To create a nature-inspired design for stable and efficient ZIBs.

Main Methods:

• Fabrication of a gradient-networked hydrogel using poly(vinyl alcohol) (PVA), cellulose nanofiber (CNF), and graphene oxide (GO).
• Characterization of the hydrogel's network density, ion transport, and interfacial properties.
• Testing of Zn-symmetric cells and Zn-MnO2 full cells for stability and performance.

Main Results:

• The gradient-networked hydrogel (PVA/CNF/GO) demonstrated enhanced ion transport and stabilized zinc deposition.
• The hydrogel enabled Zn-symmetric cells to achieve over 2200 hours of stability at 1 mA cm⁻².
• Zn-MnO2 full cells exhibited improved rate capability and safety under stress.

Conclusions:

• The developed hydrogel electrolyte effectively balances reaction kinetics and zinc deposition stability in ZIBs.
• The nature-inspired gradient-networked design offers a viable strategy for high-performance ZIBs.
• This work paves the way for more stable and efficient aqueous ZIB technologies.