摘要
Alloying is an important strategy in tailoring the functionality of materials.In metal nanoclusters(NCs),the introduction of a heterometal leads to alloy nanoclusters that often outperform the homometal ones in terms of the physical and chemical properties.In this work,a series of four M_(144)(PET)60 alloy NCs(where,M=Au/Ag,PET=–SCH_(2)CH_(2)Ph)are synthesized and characterized.The silver doping into the homogold template(Au_(144))leads to more prominent optical absorption features in the steady-state spectrum in the visible range.Femtosecond transient absorption spectroscopy reveals the effect of Ag doping on the electronic relaxation dynamics compared to Au_(144)and the pump fluence independent dynamics.Electrochemical results reflect a narrowing of HOMO–LUMO gap(E_(g))induced by Ag doping.A temperature dependence of the single-electron charging is also observed for the series of alloy NCs,in which the E_(g)values of the alloy NCs enlarge as the temperature decreases,which is characteristic of semiconducting behavior.
基金
R.J.thanks the financial support from the National Science Foundation(No.DMR-1808675)
G.W.acknowledges the funding support from National Science Foundation PAPID CHE(No.2034498)
H.W.thanks the financial support from,the Air Force Office of Scientific Research(AFOSR)Nos.(FA9550-17-1-0099 and sFA9550-21-1-0192).
