Isonitrile-functionalized ruthenium nanoparticles: intraparticle charge delocalization through Ru=C=N interfacial bonds.

Zhang, Fengqi; Huang, Lin; Zou, Jiasui; Yang, Jun; Kang, Xiongwu; Chen, Shaowei

Ruthenium nanoparticles (2.06 ± 0.46 nm in diameter) stabilized by 1-hexyl-4-isocyanobenzene (CNBH), denoted as RuCNBH, were prepared by the self-assembly of isonitrile molecules onto the surface of 'bare' Ru colloids by virtue of the formation of Ru=C=N− interfacial bonds. FTIR measurements showed that the stretching vibration of the terminal −N≡C bonds at 2119 cm for the monomeric ligands disappeared and concurrently three new bands at 2115, 2043, and 1944 cm emerged with RuCNBH nanoparticles, which was ascribed to the transformation of −N≡C to Ru=C=N− by back donation of Ru-d electrons to the π* orbital of the organic ligands. Metathesis reaction of RuCNBH with vinyl derivatives further corroborated the nature of the Ru=C interfacial bonds. When 1-isocyanopyrene (CNPy) was bounded onto the Ru nanoparticles surface through Ru=C=N interfacial bond (denoted as RuCNPy), the emission maximum was found to red-shift by 27 nm, as compared to that of the CNPy monomers, along with a reduced fluorescence lifetime, due to intraparticle charge delocalization that arose from the conjugated Ru=C=N− interfacial bonds. The results of this study further underline the significance of metal−organic interfacial bonds in the control of intraparticle charge-transfer dynamics and the optical and electronic properties of metal nanoparticles.

ISOCYANIDES; RUTHENIUM; NANOPARTICLES; DELOCALIZATION energy; INTERFACIAL bonding

Journal of Nanoparticle Research, 2017, Vol 19, Issue 9, p1

1388-0764

Academic Journal

10.1007/s11051-017-4010-8