Anisotropic growth and strain-induced tunable optical properties of Ag–ZnO hierarchical nanostructures by a microwave synthesis method.

Effective surface-enhanced Raman scattering (SERS) substrate with hierarchical nanostructure is successfully fabricated by architecturing Ag nanoparticles on the surface of one dimensional (1-D) semiconducting ZnO nanospikes. The influence of anisotropic growth and strain in the ZnO nanostructures through microwave treatment with the different time interval of microwave exposure. Based on the obtained physiochemical characterization results, the Ag–ZnO hierarchical nanostructures facilitates to modify the band structure due to the formation of heterojunction and thus drastically improves the SERS sensing capacity towards the various chemically harmful species. It is proposed that the anisotropic growth and strain-induced effect would be a unique strategy for designing and development of high-performance chemical and real-time molecular sensors. Image 1 • ZnO–Ag hierarchical nanostructures were fabricated by a microwave synthesis approach. • Influence of microwave treatment facilitates the anisotropic growth and strain induced in the nanostructures. • ZnO–Ag hierarchical nanostructure significantly enhances the SERS sensing performance. [ABSTRACT FROM AUTHOR]