Economical and green synthesis of Cu nanowires and their use as a catalyst for selective hydrogenation of cinnamaldehyde

Abstract

The reduction of Cu(OH)₂ by hydrazine in a concentrated NaOH solution containing ethylenediamine at 70 °C has been employed to prepare Cu nanowires. The net change during nanowire synthesis is that the consumption of Cu(OH)₂ and hydrazine gives rise to the formation of Cu nanowires, N₂ and H₂O, which make it possible for us to endlessly reuse the produced wastewater after the removal of Cu nanowires. By controlling the re-added amounts of hydrazine and ethylenediamine in the case of reusing the wastewater, we have found that the morphology of Cu nanowires is kept almost unchanged even though the wastewater is recycled more than ten times. The recycle of the endlessly reusable wastewater not only significantly reduces the cost of Cu nanowires but also makes this approach environmentally friendly. In addition, as a catalyst for selective hydrogenation of cinnamaldehyde, the as-formed Cu nanowires show different catalytic performance in comparison with the unsupported Cu nanoparticles.