Green strategy of scaleably synthesizing copper nanocomposites with remarkable catalytic activity for wastewater treatment

Abstract

The functional copper nanocomposites (Cu NCs) have received increasing attention in the environmental catalysis application for wastewater treatment due to their superior catalytic activity and reactivity. However, overcoming the pH limitations towards the neutral and alkaline wastewater remains a tricky challenge. In this work, we demonstrate a green strategy to synthesize Cu NCs with coexistence of active Cu, Cu2O and ZrO2 by self-propagating combustion of metallic glassy ribbons, which exhibit the extremely superior catalytic performance for degradation reaction, providing full conversion of organic dyes completely to the environmental friendly small species (efficiency > 99%) under acidic, neutral and alkaline conditions. Compared with all other catalysts developed thus far, the novel Cu NCs catalysts with more active sites present much enhanced catalytic capability of degradation efficiency without the use of any chemical reagents for neutral and alkaline organic dye solutions. The possible decomposition pathways of organic dyes for different pH systems were systematically investigated. More importantly, the two kinds of catalytic mechanism related to high reactivity of nanoscale Cu/Cu2O and strong oxidizing capability of activated ·OH /·O2− radicals can also be successfully confirmed under different pH conditions. The green synthetic approach can be extended to design the various M-based nanocomposites (M = Fe, Co, Ni, Ag, Pd) as efficient catalysts for the functional applications of many chemical reactions.