The integration of liquid metals into conductive hydrogels has long been hindered by particle instability and coalescence. Researchers from Fuzhou University have developed a novel stabilization strategy using gelatin to create a highly uniform, conductive, and stretchable hydrogel. This "electronic skin" not only monitors human motion with high sensitivity but also utilizes deep learning for real-time handwriting recognition and harvests solar energy via photothermal conversion.
Now, a research team led by Yan Yu&Sheng-Hong Zhong from Fuzhou University has turned to a common biomolecule"gelatin" to solve this "sticky" problem, creating a multifunctional hydrogel that can sense, learn, and even harvest energy.
The study, published in the journal Nano Research on June 23, describes a simple yet elegant strategy where gelatin molecules self-assemble on the surface of liquid metal particles (LMPs) through coordination bonding between amino/carboxyl groups and the metal's oxide layer. This creates a stable "shell" that prevents the metal from merging, ensuring a perfectly uniform distribution within the hydrogel network.
"The beauty of this system is its simplicity and bio-friendliness," says Professor Yan Yu, the lead corresponding author. "Gelatin isn't just a stabilizer; it actually helps 'kickstart' the polymerization of acrylic acid without the need for harsh chemical initiators. This makes the entire fabrication process faster and more sustainable."
The resulting Gelatin-Mediated Hydrogel (GMH) possesses remarkable physical properties, including the ability to stretch over 700% of its original length and recover its shape without losing performance. Beyond its mechanical toughness, the team showcased the material's "intelligence" through two primary applications:
- AI-Enhanced Handwriting Recognition: By attaching the hydrogel to a finger, the researchers recorded the unique electrical signatures of writing 26 English letters. Using a Convolutional Neural Network (CNN), the system achieved a 93.3% accuracy rate in identifying the letters in real-time, pointing toward a future of seamless human-machine interaction.
- Solar-to-Electric Energy Harvesting: The liquid metal within the gel acts as an efficient photothermal agent. Under near-infrared light, the hydrogel heats up rapidly. When paired with a thermoelectric module, it transforms this heat into electricity (~16 mV), offering a path toward self-powered wearable devices that don't rely on external batteries.
"Our work provides a versatile and scalable platform," adds Dr. Shenghong Zhong. "By stabilizing liquid metal with natural biomolecules, we are moving closer to 'electronic skins' that are as functional, adaptive, and autonomous as biological ones."
The study was conducted at the Key Laboratory of Advanced Materials Technologies, Fuzhou University. The project received support from the National Key R&D Program of China (2020YFA0710303) and the Natural Science Foundation of Fujian Province (No. 2024J01258).
DOI Link:
https://doi.org/10.26599/NR.2026.94908692
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.
