On March 15th (Reporter Shi Junbin), Jia Chunlin Scientists Studio at Xi'an Jiaotong University successfully prepared high-quality (111) oriented CoFe2O4 epitaxial nano arrays on flexible mica substrates using chemical etching self-assembly of 1-3 type nanocomposite films, and studied their magnetic properties. The above research results were published in the materials journal Materials Horizons and recommended as the cover article for the current issue.

From tech giants to startups, everyone is full of aspirations for flexible wearable devices. In the medical field, the development and application of flexible electronics are the mainstream direction for people's future life and health monitoring and treatment. Therefore, flexible materials have attracted widespread attention from scientists due to their unique bending properties and potential applications in flexible wearable electronic devices. Magnetic materials, especially one-dimensional nanostructures with high orientation, are also a research focus for researchers due to their important applications in high-density magnetic storage and sensors.

During the preparation process, researchers observed the volume increase effect of negative Poisson's ratio in the unit cell structure of CoFe2O4 nanoarrays through high-resolution X-ray diffraction. The nanoarrays prepared by this method have good crystal quality and magnetic properties, and maintain considerable ferromagnetism even at small scales. In the bent state, the hysteresis loop of the nanoarray exhibits a trend dominated by magnetic crystal anisotropy and shape factors, providing new ideas for the design of future bent magnetic sensing and magnetic control devices. Researchers observed the volume increase effect of negative Poisson's ratio in the unit cell structure of CoFe2O4 nanoarrays through high-resolution X-ray diffraction. The nanoarrays prepared by this method not only have excellent crystal quality and magnetic properties, but also exhibit a hysteresis loop dominated by magnetic crystal anisotropy and shape factors in the bent state, providing new ideas for the design of future bent magnetic sensing and magnetic control devices. This achievement brings high-performance wearable electronic devices and other devices that combine bending and flexibility features closer to the manufacturing process.

This research has received support from major special and general projects of the National Natural Science Foundation of China, the National "973" Project, the Postdoctoral Fund, the National Basic Research Development Program, and the Basic Research Funds for Central Universities.