Raspberry-structured silver-carbon hybrid nanoparticle clusters for high-performance capacitive deionization

An aerosol-based synthetic approach, in combination with a real-time characterization method using differential ion-mobility analyses coupled to temperature-programmed Fourier-transform infrared spectroscopy (DMA/TPFTIR), was demonstrated for the development of raspberry-structured Ag-carbon hybrid nanoparticle clusters (Ag-C-NPC). Physical size, number concentration, and compositions of the Ag-C-NPC were shown to be successfully characterized directly in the aerosol state on a quantitative basis. Remarkable high salt adsorption capacity (15.6 mg/g), good charging/discharging stability, and low requirement of cell voltage were attainable by using the Ag nanoparticle-decorated carbon nanoparticle clusters as the positive electrode material. This work provides a proof of concept of using the aerosol-based synthesis, with the support of in-situ characterization, for the development of Ag-C nanocomposite clusters to achieve high CDI performance. The method also shows promise for the tuning of the material properties of Ag-C-NPC for the optimization of the CDI capacity and cyclic stability useful for a variety of the water desalination applications (e.g., brackish water).