Using electrospray ionization-tandem mass spectrometry to explore formation and gas-phase chemistry of silver nanoclusters generated from the reaction of silver salts with NaBH4 in the presence of bis(diphenylarsino)methane

Abstract

Electrospray ionization-mass spectrometry (ESI-MS) of mixtures of AgBF4 or AgNO3 with the capping ligand bis(diphenylarsino)methane ((Ph2As)2CH2 = dpam) in a solution of acetonitrile revealed the formation of the following cations: [Ag(CH3CN)(dpam)]+, [Ag(dpam)2]+, [Ag2(Cl)(dpam)2]+, and [Ag3(Cl)2(dpam)3]+. Addition of NaBH4 to these solutions results in the formation of the cluster cations [Ag2(BH4)(dpam)2]+, [Ag2(BH4)(dpam)3]+, [Ag3(H)(BH4)(dpam)3]+, [Ag3(BH4)2(dpam)3]+, [Ag3(H)(Cl)(dpam)3]+, and [Ag3(I)(BH4)(dpam)3]+, as established by ESI-MS. Use of NaBD4 confirmed that borohydride is the source of the hydride in these clusters. An Orbitrap Fusion LUMOS mass spectrometer was used to expl..