Synthesis and characterization of alternated (humic acid/Fe3Â +)n multilayer film on alumina fiber

► The (humic acid/Fe3 +)n coated alumina fiber was prepared for the first time. ► The prepared samples possess large BET surface areas and great absorbabilities. ► The produced samples possess ferromagnetic property at room temperature. ► These samples possess potential application in catalytic and drug delivery areas. ► Carbonization analysis of (humic acid/Fe3 +)n was performed for the first time.