A synchronous nucleation and passivation strategy for controllable synthesis of Au36(PA)24: unveiling the formation process and the role of Au22(PA)18intermediate

Despite the recent progress on controllable synthesis of alkynyl-protected Au nanoclusters, the effective synthetic means are very limited and the cluster formation process still remains puzzling. Here, we develop a novel synchronous nucleation and passivation strategy to fabricate Au-36(PA)(24)(PA=phenylacetylenyl) nanoclusters with high yield. In Au-36(PA)(24)formation process, Au-22(PA)(18)as key intermediate was identified. Meanwhile, Au-22(PA)(18)can be synthesized under a low amount of reductant, and by employing more reductants, Au-22(PA)(18)can turn into Au-36(PA)(24)eventually. Moreover, the structure evolution from Au-22(PA)(18)to Au-36(PA)(24)is proposed, where four Au(13)cuboctahedra can yield one Au(28)kernel. Finally, the ratiocination is verified by the good accordance between the predicted intermediate/product ratio and the experimental value. This study not only offers a novel synthetic strategy, but also sheds light on understanding the structural evolution process of alkynyl-protected Au nanoclusters at atomic level.