Metal nanoparticle-loaded hierarchically assembled ZnO nanoflakes for enhanced photocatalytic performanceElectronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00043e

We have demonstrated an environmentally friendly and template-free aqueous synthesis of hierarchically assembled 3D ZnO nanoflakes. The ZnO nanoflakes self-assembled to expose highly interconnected networks of well-defined catalytic active {0001} facets. Well dispersed Pt, Ag and Au metal nanoparticles were loaded to form hybrid ZnO nanoflakes for enhanced photocatalytic activity. The enhanced photocatalytic activity may be attributed to the synergetic effects of well-structured ZnO crystal facets, high metal nanoparticles dispersity, enhanced light absorption and charge-transfer kinetics which leads to high photocatalytic degradation. Hierarchically assembled 3D ZnO nanoflakes with well-defined catalytically active {0001} facets and dispersed metal nanoparticles for enhanced photocatalytic degradation have been investigated.