Crystal-plane effect of Cu2O templates on compositions, structures and catalytic performance of Ag/Cu2O nanocomposites

Various Ag/Cu2O nanocomposites were prepared via the galvanic replacement reaction involving AgNO3 reacting respectively with uniform Cu2O cubes and octahedra. Their compositions and structures were comprehensively characterized microscopically and spectroscopically. The results reveal that the crystal plane of employed Cu2O solid templates determines the compositions and structures of the resulting Ag/Cu2O nanocomposites. A smooth surface mixed with nanoneedles or nanosheets of Ag/c-Cu2O structures was fabricated on Cu2O cubes while flocculent Ag/o-Cu2O structures were fabricated on Cu2O octahedra. The catalytic performance of Ag/Cu2O nanocomposites were evaluated in CO oxidation with excess O-2. In situ surface restructuring occurs on various Ag/Cu2O nanocomposites to form Ag-CuO/Cu2O nanocomposites. The catalytic activity of the resulting Ag-CuO/Cu2O nanocomposites depends on the structures of CuO and Ag that are affected by the original crystal plane of Cu2O solid templates and the Ag loading. These results broaden the crystal-plane effect of Cu2O nanocrystals as solid templates for synthesis of multicomponent nanocomposites via liquid-solid interfacial reactions.