In this paper, zwitterionic graphene oxide (ZGO) was prepared with two silanes. It was evident that the silane molecules were grafted on GO surfaces by covalent bondings. ζ potential of ZGO varied from -29.0 mV to +28.5 mV when the pH of the aqueous solution was changed from 12 to 2. As a result, the ZGO can be dispersed in both anionic and cationic waterborne polymer matrix. Besides, ZGO can be used as two-dimensional surfactant in a wider range of pH values than GO. The multi-applications of ZGO were enabled by the unique pH-responsive charge-conversion properties and pH-insusceptible amphiphilicity.

中文翻译：

---

用两个硅烷分子改性的两性离子氧化石墨烯可用于多种应用

本文用两种硅烷制备了两性离子氧化石墨烯（ZGO）。显然，硅烷分子通过共价键接枝在GO表面。当水溶液的pH值从12变为2时，ZGO的ζ电势从-29.0mV变化至+ 28.5mV。结果，ZGO可以分散在阴离子和阳离子水性聚合物基质中。此外，ZGO可以在比GO更宽的pH值范围内用作二维表面活性剂。ZGO的多种应用通过独特的pH响应电荷转换特性和pH不敏感的两亲性得以实现。