More octahedral Cu+ and surface acid sites in uniformly porous Cu-Al2O3 for enhanced Fenton catalytic performances

Abstract

Porous Cu-doped alumina (P-Cu-Al2O3) has been synthesized using ammonium chloride as a green gaseous template. The unique pore-forming agent endows the catalyst a large surface area and homogenous pore structure. According to the characterization results by multi-technologies, the highly dispersed framework Cu+/Cu2+ was incorporated in octahedral sites with the formation of the Cu-O-Al bonds. Compared with bulk Cu-doped Al2O3 (B-Cu-Al2O3), more surface acidic oxygen-containing groups and Lewis acid sites existed in P-Cu-Al2O3, resulting in the production of surface adsorbed •OH, which is helpful for the removal of surface adsorbed organic intermediates. In addition, O2 more easily participate in surface reaction to promote the •OH generation in P-Cu-Al2O3 system than that in B-Cu-Al2O3. As a result, the representative endocrine disruptor bisphenol A can be more efficiently mineralized by P-Cu-Al2O3. This work provides a facile route to develop porous active heterogenous Fenton-like catalysts and a unique perspective to insight into the structure-activity relationship.