Partial Phosphorization: A Strategy to Improve Some Performance(s) of Thiolated Metal Nanoclusters Without Notable Reduction of Stability

Thiolates endow metal nanoclusters with stability while sometimes inhibit the catalytic activity due to the strong M-S interaction (M: metal atom). To improve the catalytic activity and keep the stability to some extent, one strategy is the partial phosphorization of thiolated metal nanoclusters. This is demonstrated by successful partial phosphorization of Au-23(SC6H11)(16) and by revealing that the products Au-22(SC6H11)(14)(PPh3)(2) and Au-22(SC6H11)(12)(PPh3)(4), with varied degree of phosphorization, both show excellent activity in the photocatalytic oxidation of thioanisole without notable reduction of stability. Furthermore, Au-22(SC6H11)(12)(PPh3)(4) exhibits better photoluminescence performance than the mother nanocluster Au-23(SC6H11)(16), indicating that partial phosphorization can also improve some other performance(s) except for the catalytic performance. The intermediates Au22-xCux(SC6H11)(12)(PPh3)(4) (x=1, 2) in the transformation from Au-23(SC6H11)(16) (Au-22(SC6H11)(14)(PPh3)(2)) to Au-22(SC6H11)(12)(PPh3)(4) were captured and identified by mass spectrometry and single crystal X-ray diffraction, which throws light on the understanding of the non-alloyed anti-galvanic reaction.