A one-pot synthesis of a monolithic CuO/Cu catalyst for efficient ozone decomposition.

Nowadays, it is necessary and challenging to prepare monolithic catalysts, which are ready for use, preventing the tedious and complicated integration procedure of the powder materials onto a porous substrate. Herein, CuO nanoparticles are successfully synthesized onto a porous Cu foam in one pot the surface oxidation, coordination and precipitation reactions in a NHOH and HCl solution, and the optimum synthesis conditions are a NH : HCl ratio of 1 : 0.9, oxidation temperature of 80 °C and time of 18 h. The obtained CuO/Cu catalyst (mostly <100 nm) shows a highly active O decomposition performance with >98% and >80% conversion efficiency in dry and 90% relative humidity air for >10 h at an O concentration of 20 ppm and a gas hourly space velocity of 12 500 h. The high efficiency can be attributed to the porous Cu foam providing a large contact area, abundant crystal defects in the nanometer-sized CuO materials serving as the active sites, and also to the Schottky barrier formed in the CuO/Cu interface facilitating the electron transfer for O degradation. All these results show the potency of the easily fabricated monolithic CuO/Cu catalyst for the highly efficient O contaminant removal.