We report a new method for the green synthesis of ZnO nanoparticles. A new leucine-based diamine amphiphile was synthesized and self-assembled, which in the presence of Zn(2+) ions assembled into nanofibers, that efficiently formed ZnO nanoparticles upon heating in the presence of Zn(CH(3)COO)(2). Further, these ZnO nanoparticles functioned as efficient photocatalysts.