Atomically Engineered Trimetallic Nanoclusters Toward Enhanced Photoluminescence and Photoinitiation Activity

Abstract Precise doping is of vital significance for atomic engineering and the establishment of structure‐property relationships in nanocluster (NC) chemistry. Herein, two novel trimetallic MAu 18 Cd 3 (M = Pd/Pt) NCs that are derived from M‐doped Au 25 templates of MAu 24 are reported, in which the central doping of M atom and the surface‐motif doping of Cd atoms are concurrently achieved. Compared to the original templates, Cd‐induced surface engineering enhances the rigidity of the structural framework and enlarges the HOMO‐LUMO gaps of the MAu 18 Cd 3 , significantly improving photoluminescent efficiency by suppressing nonradiative relaxation. The critical role of the central M (Pd/Pt) dopant in photoluminescence, which regulates the rate of radiative decay of excited‐state electrons, has also been substantiated. More notably, the doped case of PtAu 18 Cd 3 exhibits excellent photoinitiation activity in 3D two‐photon printing with a high resolution of ≈140 nm, which may be attributed to the prolonged excited state. Overall, this work provides a generalized routine for the precise synthesis of multi‐metal NCs with concurrent enhancements in photoluminescence and photoinitiation activity, which is expected to stimulate further research for the design and preparation of multi‐functional, multi‐metal NCs.