The exfoliation of layered oxides to prepare nanosheets and the subsequent modification of nanosheet surfaces via standard techniques can take days. Microwave methods are well-known for facilitating specific chemical reactions, yielding better outcomes in a very short time.
John B. Wiley, University of New Orleans, LA, USA, and colleagues have used microwaves for the efficient exfoliation of double-layered Dion-Jacobson perovskites in 1–2 hours. HLnNb2O7 perovskites (Ln = La, Pr) were efficiently exfoliated in aqueous solutions of tetra(n-butyl)ammonium hydroxide (TBAOH), producing TBA-functionalized nanosheets (<2 nm thick).
Using a microwave approach, a post-exfoliation surface modification of the obtained metal-oxide nanosheets was also possible in under one hour. The TBA+ surface groups were readily replaced with various linear or cyclic organic molecules that contain hydroxyl or amine functional groups.
These methods should be applicable to a large number of layered oxides and organic surface moieties. They could allow the rapid production of various 2D hybrids with potentially novel electronic, magnetic, optical, and mechanical properties.
- Rapid Exfoliation and Surface Tailoring of Perovskite Nanosheets via Microwave-Assisted Reactions,
Sara Akbarian-Tefaghi, Taha Rostamzadeh, Treva T. Brown, Clare Davis-Wheeler, John B. Wiley,