Synthesis of Fe₃O₄ polyhedra by hydrothermal method: using l-arginine as precipitator

摘要

Unusual polyhedral structures of cubic Fe₃O₄ were fabricated in high yield via a facile hydrothermal method in the presence of a surfactant cetyltrimethyammonium bromide (CTAB). Hexagonal, dodecahedral, truncated octahedral, and octahedral shapes can be prepared by changing the concentration of the CTAB in l-arginine solutions. In the solution-phase synthesis, both the l-arginine and CTAB were found to be the prime factors for the formation of the polyhedral structures. In addition, room-temperature vibrating sample magnetometer (VSM) testing results indicated that the magnetite synthesized without the addition of CTAB had the highest M _s value and the lowest H _c value. This synthesis method is also suitable for the preparation of other ferrites with spinel structure.