It is a dream of researchers to be able to tailor the catalytic performances by adjusting heterogeneous catalysts at the atomic level. Atomically precise metal clusters provide us with the possibility to achieve this challenge. Here, we design a push‐and‐pull synthesis strategy coupled with TiOx coating to prepare the heterogeneous catalysts denoted as TiOx/Au8M@SBA via cultivating atomically precise Au8M(PPh3)8n+ (M = Pd, Pt or Au; n = 2 for Pd/Pt and 3 for Au) clusters in mesoporous molecular sieve. The catalysts are made up of the three functional units, which include Au8M(PPh3)8n+ clusters that can act as the active sites, the pore environment of the SBA‐15 that can announce a catalysis show for the clusters with precise number of atoms maintained during the chemical reactions, and the TiOx coating that can further inhibit the migration of the clusters under reaction conditions. The selective hydrogenation of acetylene performed in the fixed‐bed reactor taken, for example, we learn how the atom‐by‐atom tailoring of a heterogeneous catalyst can switch on elusive heterogeneous mechanisms with cluster catalysis. This work sheds light on the fundamental insight into catalysis origin of heterogeneous catalysts and achieves a distinguished level of detail for cluster catalysis.
