A new cobalt(II) complex nanosheet as an electroactive medium for plasmonic switching on Au nanoparticles.

2D metal-organic complex nanosheets with the merits of high stability and structure tunability are an emerging topic in recent years. To extend the promising ultrathin architectures, a new Co(II) complex nanosheet (Co-nanosheet) is designed and prepared a readily operated interface-assisted coordination reaction between the ligand 4,4'',4'''-(2,4,6-trimethylbenzene-1,3,5-triyl)tris(2,2':6',2''-terpyridyl) (L) and Co ions. The as-formed Co(II) complex nanosheet exhibits both a uniform layered structure and good thermostability as proposed, which were verified by various chemical and physical analytical methods. Moreover, it is first utilized as an electroresponsive medium to tune the surface plasmon resonance behavior of Au nanoparticles, expanding the applicable fields of this type of 2D materials.