CuO nanoflakes  prepared via a simple one-step wet chemical route at moderate condition using hexamine as a surfactant. 

follow one of my frnd working in this field 

https://www.researchgate.net/publication/301739530_PVP_Assisted_Shape-Controlled_Synthesis_of_Self-Assembled_1D_ZnO_and_3D_CuO_Nanostructures

Article PVP Assisted Shape-Controlled Synthesis of Self-Assembled 1D...

This work may be useful to you.  Direct formation of small Cu2O nanocubes, octahedra, and octapods for efficient synthesis of triazoles.

Please check this article it may be helpful

Dear Hamid,

You can try green and eco-friendly synthesis of Cu2O nanoparticles.

https://www.nature.com/articles/srep07339

http://www.tandfonline.com/doi/pdf/10.1080/17458080.2015.1015462

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5127256/

http://www.sciencedirect.com/science/article/pii/S0167577X15304109

With best wishes,

Swarup Roy

thanks for all