Subnanometer noble metal clusters have enormous potential, mainly for catalytic applications. Because a difference of only one atom may cause significant changes in their reactivity, a preparation method with atomic-level precision is essential. Although such a precision with enough scalability has been achieved by gas-phase synthesis, large-scale preparation is still at the frontier, hampering practical applications. We now show the atom-precise and fully scalable synthesis of platinum clusters on a milligram scale from tiara-like platinum complexes with various ring numbers (n = 5–13). Low-temperature calcination of the complexes on a carbon support under hydrogen stream affords monodispersed platinum clusters, whose atomicity is equivalent to that of the precursor complex. One of the clusters (Pt10) exhibits high catalytic activity in the hydrogenation of styrene compared to that of the other clusters. This method opens an avenue for the application of these clusters to preparative-scale catalysis.

There has been controversy surrounding the roles of the metal core (metal–metal interaction) and the shell (metal–ligand interaction) in photoluminescence of ligand‐protected metal nanoclusters. We have discovered aggregation‐induced room‐temperature phosphorescence of a platinum–thiolate complex and its silver ion inclusion complex (a silver‐doped platinum sub‐nanocluster). The inclusion of silver ion boosted the photoluminescent quantum yield by 18 times. Photophysical measurements indicate that the rate of nonradiative decay was slower for the silver‐doped platinum sub‐nanocluster. DFT calculations showed that the LUMO, which had the main contribution from Ag s‐orbital and Pt d‐orbitals, played a critical role in suppressing the structural distortion at the excited state. This work will hopefully stimulate more research on designing strategies based on molecular orbitals of atomicity‐precise luminescent multimetallic nanoclusters.

There has been controversy surrounding the roles of the metal core (metal–metal interaction) and the shell (metal–ligand interaction) in photoluminescence of ligand‐protected metal nanoclusters. We have discovered aggregation‐induced room‐temperature phosphorescence of a platinum–thiolate complex and its silver ion inclusion complex (a silver‐doped platinum sub‐nanocluster). The inclusion of silver ion boosted the photoluminescent quantum yield by 18 times. Photophysical measurements indicate that the rate of nonradiative decay was slower for the silver‐doped platinum sub‐nanocluster. DFT calculations showed that the LUMO, which had the main contribution from Ag s‐orbital and Pt d‐orbitals, played a critical role in suppressing the structural distortion at the excited state. This work will hopefully stimulate more research on designing strategies based on molecular orbitals of atomicity‐precise luminescent multimetallic nanoclusters.