<p>The growing usage of industrial dyes makes the sewage treatment a global issue, therefore low-cost, highly efficient catalysts are urgently demanded for wastewater purification. We present an ultrasonic-engineered catalytic technology, which can achieve an extremely high efficiency in azo dye degradation via a tiny dosage of 0.1 g L⁻¹ (only one-fifth of the normally used dosage) Fe₈₁Si₉B₁₀ amorphous powders (APs) with a low activation energy of 45.32 kJ mol⁻¹ and a high reaction rate of 0.70291 min⁻¹. The non-destructive ultrasonic vibration (UV) treatment with very short processing times (0.43–1.08 s) amplifies degradation efficiency by an astonishing 55-fold compared to untreated APs. Combined with high-energy X-ray diffraction and small-angle neutron scattering analyses, we reveal that the UV-induced structural reconstruction at both short- and medium-range order effectively lower reaction energy barriers while accelerating charge transfer kinetics. The high-energy ultrasonic attacks promote the exposure of massive fresh active sites, which enhance the Fe²⁺/Fe³⁺ redox circulation and thereby lead to the fast Fenton-like oxidation processes. By integrating ultrasonic physics with amorphous materials, this work develops an energy-efficient catalytic activation method, enabling sustainable water purification and innovative pollutant treatment strategies.</p>