Monodispersed Ag nanoparticles loaded on the PVP-assisted synthetic Bi2O2CO3 microspheres with enhanced photocatalytic and supercapacitive performances

Uniform 1 mu m-sized Bi2O2CO3 microspheres constructed by nanoplates with a thickness of about 12 nm have been obtained through a facile hydrothermal method. Ag is deposited on the surface of Bi2O2CO3 via a subsequent facile photoreduction process. In the synthesis process, polyvinylpyrrolidone (PVP) is used as a reactant that not only provides C and O sources but also serves as a template to induce the nanoplate-assembly to form microspheres. With the addition of KCl in the synthesis, the size of the Bi2O2CO3 microspheres can be reduced from similar to 6 mu m to similar to 1 mu m. It is demonstrated that PVP and KCl play key roles in the formation of such hierarchical microspheres. The obtained Bi2O2CO3 and novel Ag/Bi2O2CO3 composites are evaluated for photocatalytic and supercapacitive applications. The test result of the photocatalytic activity demonstrates that 0.6 wt% loading of Ag on the Bi2O2CO3 microspheres exhibits significantly enhanced activity for the photodegradation of methyl orange (MO) dye, compared with Bi2O2CO3. The enhanced photocatalytic activity can be attributed to the Ag deposits acting as electron traps and the high surface area of Bi2O2CO3. Furthermore, the Ag/Bi2O2CO3 composites are primarily evaluated as supercapacitor electrodes, which deliver specific capacities of 620 and 361 F g(-1) at current densities of 1 and 5 A g(-1), respectively.