Wu Yuchen, Jiang Gaopeng, Li Qian, Zhang Zisheng, Chen Zhongwei
Department of Chemical and Biological Engineering, University of Ottawa 161 Louis Pasteur Private Ottawa Ontario K1N 6N5 Canada
Department of Chemical Engineering, University of Waterloo 200 University Ave W Waterloo Ontario N2L 3G1 Canada
RSC Adv. 2019 Sep 9;9(48):28186-28193. doi: 10.1039/c9ra05380h. eCollection 2019 Sep 3.
In this work, the first-ever reported nanocomposite electrode of nitrogen-doped graphene-titanium oxynitride (NG-TiO N ) for capacitive deionization (CDI) was synthesized hydrothermal reaction and a high-temperature nitridation process. The physiochemical characterizations revealed that the nitrogen was doped in the graphene structure mainly in the form of graphitic nitrogen and the TiO N was successfully formed TiO nitridation process. The layered NG nanosheets facilitated the diffusion of ions in saline water and formed electrical double layer on the surface of the electrode material, while the presence of TiO N enhanced the electrochemical performance by increasing surface area and generating surface vacancies nitridation. The CDI cell employed NG-TiO N electrode delivered a breakthrough salt adsorption capacity of 26.1 mg g in 500 mg L saline water, and retained over 90% of its initial salt removal efficacy after 12 regeneration cycles. Such high CDI performance exhibits the promising application of NG-TiO N as a novel CDI electrode candidate.
在本工作中，通过水热反应和高温氮化工艺合成了有史以来首次报道的用于电容去离子化（CDI）的氮掺杂石墨烯-氮氧化钛（NG-TiOₓNₙ）纳米复合电极。物理化学表征表明，氮主要以石墨氮的形式掺杂在石墨烯结构中，并且通过TiOₓ氮化工艺成功形成了TiOₓNₙ。层状的NG纳米片促进了盐水中离子的扩散，并在电极材料表面形成了双电层，而TiOₓNₙ的存在通过增加表面积和在氮化过程中产生表面空位来提高电化学性能。采用NG-TiOₓNₙ电极的CDI电池在500 mg L盐水中实现了26.1 mg g的突破性盐吸附容量，并且在12次再生循环后仍保留了其初始脱盐效率的90%以上。如此高的CDI性能表明NG-TiOₓNₙ作为一种新型CDI电极候选材料具有广阔的应用前景。
