摘要
Copper tungstate (CuWO 4 ) decorated 2-dimensional reduced graphene oxide (CWO/rGO) has been successfully fabricated via solvothermal synthesis at 180 °C for 12 h, and then utilized for capacitive deionization (CDI) applications. After deposition of 20 – 40 nm spherical CuWO 4 nanoparticles onto few-layered rGO nanosheets, the specific surface area can be up to 338 m 2 g −1 with abundant 2 – 10 nm mesopores, which can accelerate the ion transport to augment the electrochemical performance. The CWO/rGO nanocomposite also exhibits high specific capacitances of 380 and 327 F g −1 at 0.5 A g −1 and 5 mV s −1 , respectively. Furthermore, the specific electrosorption capacity (SEC) of CWO/rGO is highly dependent on environmental parameters including NaCl concentration, flow rate, applied potential, and solution temperature. An excellent SEC of 54.1 mg g −1 is achieved when 1000 mg L -1 NaCl was used at 1.4 V. Both Faradaic and electric double layer capacitances contribute the electrosorption capacity to the CDI performance of CWO/rGO where CuWO 4 provides electroactive sites and rGO enhances the electric conductivity as well as offers mesoporous channels for electrosorption of ions. Meanwhile, the high charge efficiency of 95 %, lower energy consumption of 0.32 kWh m −3 , and long-term stability of 50 charging-discharging cycles make the CWO/rGO a potential material for brackish water desalination, which can elucidate on the development of highly efficient desalination technologies.