Preparation of amorphous Bi-Fe-O series semiconductor and its crystallization behavior and photocatalytic activity.

In that research field of Bi-Fe-O series compounds, the design and development of amorphous Bi-Fe-O semiconductor with high photocatalytic activity and pure phase BiFeO 3 with multiferroic properties are two major challenges. Herein, the amorphous Bi-Fe-O series semiconductor is prepared by mechanical alloying method using Fe 2 O 3 and Bi 2 O 3 as the raw materials, and the pure phase nano-BiFeO 3 crystalline is subsequently obtained by heat treatment process. Meanwhile the microstructure, band gap structure and photocatalytic or electromagnetic activity of amorphous and crystallized Bi-Fe-O semiconductor are also investigated. The results show that after 25 h of mechanical alloying, the crystalline structure of Bi 2 O 3 and Fe 2 O 3 is destroyed, and the system is transformed into amorphous phase. Moreover, photocatalytic hydrogen production experiment shows that amorphous Bi-Fe-O semiconductor has the highest photocatalytic hydrogen production rate which is 4.03 μmol/g/h, due to more defects and impurity energy levels. In addition, pure phase nano-BiFeO 3 crystalline can be obtained when the heat treatment temperature of amorphous Bi-Fe-O semiconductor is 600°C, which have the best ferroelectric properties. This work not only provides new ideas for the research and development of amorphous semiconductor, but also proposes a green method to prepare pure phase nano-BiFeO 3 crystalline. • Amorphous Bi-Fe-O series semiconductors are constructed by mechanical alloying method. • Pure phase nano-BiFeO 3 is prepared by heat treatment from the amorphous Bi-Fe-O materials. • The highest hydrogen production rate of amorphous Bi-Fe-O semiconductors is 4.02 μmol/g/h. • Pure phase nano-BiFeO 3 obtained at 600°C have the best ferroelectric properties. [ABSTRACT FROM AUTHOR]