Modified Electrodes For Capacitive Deionization

As a new type of water treatment technology,CDI is energy-saving,high efficiency and environmental friendly.The essential components of CDI are carbon electrodes for desalination.In order to improve the desalination performance,lower production cost and reduce the dependency on petroleum,we modified the common electrodes in a sample and effective way.???We utilized an efficient method to activate graphene electrodes with CO₂ for different reaction time.AGE-30 had the highest electrosorption capacity?6.26 mg/g?among five samples,and this was attributed to its high specific surface area?898 m²/g?,high pore volume?1.223 cm³/g?,and high specific capacitance?56.21 F/g?at 5 mV/s.Thus,the CO₂ activation is confirmed to be a useful method for the enhancement of the graphene electrodes for CDI.???Dandelion pappus as natural resource was collected as the raw material of carbon material for CDI.After K₂CO₃ activation,the sample was named ADC and it has the electrosorption capacity of 11.42 mg/g,specific surface area of 1105 m²/g and specific capacitance of 88.4 F/g at 5 mV/s.It was an efficient way to reduce the dependency on petroleum,and realize the maximum value of biomass.???The activated carbon electrode was modified by immersing in PDC and PSS polyelectrolyte,respectively.In order to study the effect of the coated polyelectrolyte,electrodes of coated and bare activated carbon were respectively named as IEC and NEC and tested in CDI system.As the result shown,when applied 1.2 V,the desalination performance of IEC is much higher than NEC in a high concentration of sodium chloride solution.Moreover,the charge efficiency of IEC is always higher than NEC under the same test conditions.