Structure stability, fracture, and tuning mechanism of CdSe nanobelts

Zhongwu Wang, Ken Finkelstein, Chris Ma, Zhong Lin Wang
2007 Applied Physics Letters  
High pressure synchrotron x-ray diffraction studies have been conducted to explore the structural stability, phase transformation, and resulting mechanisms of CdSe nanobelts. 25-nm-thick wurtzite CdSe nanobelts transform to a rocksalt structure with in situ fracture at 4.0 GPa; this is greater than the transition pressure of 2.5 GPa in bulk and 25 nm nanoparticle. Decompression results in the formation of wurtzite and sphalerite at 1.2 GPa. Total Gibbs free energy calculations demonstrate that
more » ... s demonstrate that the low surface energy ±͕210͖ facets are fully responsible for the enhancement of structure stability. A strongest particle size for the rocksalt phase was determined ϳ12 nm, providing a significant constraint for the fracture of nanobelts and size-tuned enhancement of mechanical properties.
doi:10.1063/1.2713172 fatcat:yahofhdyqvezblz656au2kqlom