Synthesis and Properties of the Self-Assembly of Gold–Copper Nanoparticles into Nanoribbons

We report an efficient wet-chemical production of self-assembled gold-copper bimetallic nanoparticles (diameter of ~2 nm) into two-dimensional flexible ribbon-like nanostructures. A direct observation of a layered arrangement of particles into the nanoribbons was provided through high-resolution transmission electron microscopy and electron tomography. These nanoribbons showed photoluminesce and an efficient photocatalytic activity for the conversion of 4-nitrophenol. Their thermal stability of the nanoribbons was also measured by in situ heating treatment in the electron microscope, confirming that the self-assembled gold-copper nanoribbons efficiently supported up to 350 °C. The final morphology of the nanoparticles and their ability for self-assembly into flexible nanoribbons was dependent on concentration and ratio of precursors. Therefore, these experimental factors were discussed. Remarkably, the presence of copper was found to be critical to trigger the self-assembly of nanoparticles into ordered l...