Anion-responsive carbon nanosystem for controlling selenium fertilizer release and improving selenium utilization efficiency in vegetables

Abstract The application of Se fertilizers could promote plant growth and enhance Se contents of crops. However, traditional Se fertilizer tended to be lost with rainwater and caused Se pollution. Thus, it was necessary to develop a smart nanosystem to control Se fertilizer release. In this work, an anion-responsive nanosystem was prepared using polyethylenimine modified hollow/mesoporous carbon nanoparticles (PHMCN), and selenate could be effectively loaded into PHMCN (the highest loading capacity: 389 mg/g) by electrostatic attraction. The release of Se from this nanosystem could be sensitively triggered using PO43−, CO32−, and OH− as the model anions by ion exchange, and the release amount of Se was dependent on the concentration and valence of anions, so that the Se loss could be significantly reduced and the yield and Se content of vegetables increased. This work provides a promising strategy for obtaining Se-enriched vegetables and reducing Se pollution.