Superior Flexibility in Oxide Ceramic Crystal Nanofibers. Issue 44 (17th September 2021)

• Record Type: Journal Article
• Authors: Zhang, Yuanyuan; Liu, Shujie; Yan, Jianhua; Zhang, Xiaohua; Xia, Shuhui; Zhao, Yun; Yu, Jianyong; Ding, Bin
• Is Part Of: Advanced materials. Volume 33:Issue 44(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-09-17
• Subjects: ball‐milling -- curved‐drafting -- electrospinning -- flexible ceramic nanofibers -- ordered grain assembly; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202105011
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Oxide crystal ceramics are commonly hard and brittle, when they are bent they typically fracture. Such mechanical response limits the use of these materials in emerging fields like wearable electronics. Here, a polymer‐induced assembly strategy is reported to construct orderly assembled TiO2 crystals into continuous nanofibers that are stretchable, bendable, and even knottable. Ball‐milling the spinning sol and curved‐drafting the electrospun nanofibers significantly improve the molecular structural order and reduce pore defects in the precursor nanofibers. Using this method, continuous TiO2 nanofibers, in which orderly assembled TiO2 nanocrystals (brick) are connected by twin grain boundaries or an amorphous region (mortar), are formed after sintering. Mechanical measurements and finite element analysis simulation indicate that the dislocation slip of "bricks" and the elastic deformation of "mortar" render the nanofibers with a small bending rigidity of ≈22 mN and a small elastic modulus of ≈20.8 Gpa, thus displaying properties associated with both soft and hard matter. More importantly, the reported approach can be easily extended to synthesize a wide range of soft, yet tough ceramic membranes, such as ZrO2 and SiO2 . Abstract : Flexible ceramic nanofibers are fabricated using a ball‐milling‐ and curved‐drafting‐assisted electrospinning technique. With this strategy, continuous TiO2 nanofibers, in which orderly assembled TiO2 nanocrystals are connected by twin or amorphous grain boundaries, are formed after sintering. The single nanofiber is knottable, while the nanofiber membrane can be folded without fracture, displaying properties associated with both soft and hard matter.