Chinese researchers created a low-cost electrode material to facilitate seawater desalting.
Water is essential for life. Generally, fresh water is artificially provided by desalting seawater. In fact, this water-providing method could be realized by many techniques with capacitive deionization (or CDI) considered as the most promising one.
However, as for its electrode, a key component in CDI, the materials used in it are usually synthesized by oil-derived chemicals, which are very expensive especially in the mass production.
In the new work, the team used a natural plant soybean shell to create new electrode material, which dramatically reduce its cost.
In the experiment, they used the plant as starting material to firstly obtain N-doped porous carbon (NPC) by a facile pyrolysis approach. And they then took a further study to make the prepared NPC possess good ability of deionization.
This performance of NPC could make it create Zn-air battery to power the CDI setup.
This work was financially supported by the National Key R&D Program of China (2017YFA0207202), the Natural Science Foundation of China (Grant No. 51672277, 51432009), the CAS Pioneer Hundred Talents Program, and the CAS/SAFEA International Partnership Program for Creative Research Teams of Chinese Academy of Sciences, China.
Figure 1. (a) Open circuit voltage measurement of NPC assembled Zn-air battery (inset of lightened LED pattern). (b) Discharge curve and corresponding power density plot of NPC assembled Zn-air battery at different current densities. (c) Photograph of home-made Zn-air battery powered CDI setup. (d) Cycling stability of S-NPC assembled CDI setup powered by Zn-air battery.(Image by ZHAO Cuijiao)
Figure 2. N-doped porous carbon was obtained using soybean shell as precursor, followed by surface functionalization via sulfonic groups, as electrode materials exhibiting high performance of Zn-Air battery powered capacitive deionization.(Image by ZHAO Cuijiao)