Creating Nitrogen-Doped Hollow Multiyolk@Shell Carbon as High Performance Electrodes for Flow -Through Deionization Capacitors

A novel electrode material for flow-through deionization capacitors consisting of the hollow multiyolk@shell carbon (HMYSC) with effective nitrogen doping has been rationally designed and originally prepared by a template-directed coating method. The HMYSC can be divided into several hollow carbon spheres cores and the nitrogen-doped shell. The as-obtained HMYSC shows many favorable features for flow through deionization capacitors, such as large specific surface area (910 m(2) g(-1)), hierarchical pores, high conductivity and good wettability. With the multiple synergistic effects of the above features, the as-prepared HMYSC electrode has higher specific capacitance, lower inner resistance and good stability. In the deionization test, the HMYSC electrode exhibits a high salt adsorption capacity of 16.1 mg g(-1) under the applied voltages of 1.4 V in a 500 mg NaCl solution. Furthermore, it has been demonstrated that the HMYSC electrodes presented faster salt adsorption rate under the applied voltages of 0.8-1.4 V and in the NaCl solution with the concentration of 100-500 mg L-1 The HMYSC electrodes also exhibits an excellent regeneration performance in the repeated adsorption-desorption experiments. The HMYSC developed in this work is promising to be an effective electrode material for the flow-through deionization capacitors and other electrochemistry