Atomically Precise Single-Walled Cluster Nanotubes of Giant Polyoxometalates

Single-walled nanotubes have attracted extensive research interest since their discovery due to their remarkable physical and chemical properties. Here, we synthesized the single-walled cluster nanotubes with an atomically precise structure by directly linking the largest building blocks, Preyssler-type polyoxometalate clusters (each comprising ∼150 atoms) with rare-earth metal ions. The atomically precise assembly process of the nanotube enabled the capture of key growth intermediates, thereby revealing a cluster-to-cluster assembly pathway and leading to the proposal of a wall-fusion growth mechanism. Owing to electron delocalization between the internal polyoxometalate clusters, the nanotube exhibits exceptional catalytic activity for the electrocatalytic reduction of phenol to cyclohexanone, achieving 92% selectivity and 64% Faradaic efficiency. This work elucidates the molecular-level growth mechanism of single-walled cluster nanotubes and links their directional assembly to superior electron transport and catalytic efficiency, providing a conceptual foundation for the rational design of high-performance nanotube catalysts.