An amorphous zero-valent iron decorated by Fe3O4 significantly improves the Fenton-like reaction

Glassy zero-valent iron (GZVI) is one of the potential Fenton-like catalysts due to its amorphous nature and high energy state, but the catalytic activity still needs to be further enhanced, especially using low-cost technology suitable for industrialization. In this paper, Fe 3 O 4 particles were embedded into the surface of Fe 91.9 Si 5.3 B 2.8 amorphous powder through a conventional low-cost ball milling technique, which endowed Fe 3 O 4 /GZVI with improved catalytic activity. GZVI attained the best surface morphology and the highest catalytic efficiency (3 times as high as pure GZVI) at a 10% Fe 3 O 4 addition. The Fe 3 O 4 -decorated catalysts could decompose p-nitrophenol by 97.37% within 15 min and exhibited good stability and reusability within seven cycles. The galvanic cell formed between Fe 3 O 4 and GZVI because their large OCP gap was responsible for the improved catalytic activity, which promoted electron transfer and •OH generation. The faster electron mobility accelerated the oxidation of Fe 2+ and Fe 0 and the reduction of Fe 3+ on the catalyst surface with the aid of H 2 O 2 , thus promoting the pollutant degradation process. The amount and distribution of Fe 3 O 4 particles and the bonding state between Fe 3 O 4 and GZVI markedly influence the degradation reaction and reusability. Fe 3 O 4 /GZVI is a promising heterogeneous Fenton-like catalyst with low-cost and large-scale engineering application prospects. • GZVI shows significantly improved catalytic efficiency by embedding Fe 3 O 4 particles on the surface by ball milling technique. • GZVI and Fe 3 O 4 form an effective galvanic to accelerate electron transfer to promote degradation. • The amount of Fe 3 O 4 affects the surface morphology of GZVI and thus the degradation process. • Fe 3 O 4 / GZVI powder has good environmental applicability and cycle stability. • The strategy has the possibility of large-scale industrial production and application.