An instant, biocompatible and biodegradable high-performance graphitic carbon nitride

Abstract

Polymer graphitic carbon nitride (g-C₃N₄) materials have attracted growing interest owing to their impressive applicability in photocatalysis and optoelectronic devices. However, further applications of g-C₃N₄ materials are greatly restricted by their chemical inertness and insolubility in most solvents. Regarding the rising prospect of g-C₃N₄ nanosheets in the biomedicalfield, high solubility and biocompatibility are required for the further development of g-C₃N₄ materials. In this study, a simple one-step thermal polymerization method was designed to prepare fast-soluble mesoporous g-C₃N₄ nanosheets by using NH₄HSO₄ as the critical adjuvant. The products, especially the optimal g-C₃N₄ NSs-4, showed impressive solubility, biocompatibility and partial biodegradability. The enriched surface hydrophilic groups (-NH₂ and -OH) may contribute to improving the solubility of g-C₃N₄ nanosheets, while the partial biodegradability can be ascribed to the presence of the disulfide bond in the g-C₃N₄ framework. In this system, the NH₄HSO₄ adjuvant acted not only as O and S sources, but also as a bubbling agent that endows the g-C₃N₄ a porous structure with greatly enlarged specific surface area and high separation efficiency of photogenerated electron-hole pairs. These integrative positive factors also greatly contributed to the photocatalytic activity of the g-C₃N₄ nanosheets. This facile, economic and general fabrication strategy for mesoporous, fast-soluble and biocompatible g-C₃N₄ with superior visible-light photocatalytic activity is promising in environmental, energy and biomedical fields.

Keywords: Biocompatible; Biodegradable; Fast-soluble; Graphitic carbon nitride; NH(4)HSO(4).