• • Oxidized Ni atomic clusters (ONCs) as dopants in Ni micropowders (0, 1, 3, 5 mass%) yield a 38% enhancement in Vickers hardness in ODS alloy, demonstrating a viable route to utilize unstable clusters.
• • The strengthened Ni exhibits finer grains, a larger proportion of low-angle grain boundaries, and higher geometrically necessary dislocation density, indicating microstructural refinement at the atomic scale.
• • The novel concept of using oxidized metal atomic clusters in oxygen-bearing materials circumvents the fundamental challenges of low yield, inconsistent size, and susceptibility to agglomeration and sintering.
• • Four critical scientific issues—oxidation control, disaggregation and dispersion, effectiveness comparison, and physicochemical behaviors—are identified as urgent for advancing this concept, guiding future research.