External magnetic field was applied during syntheses of α-Fe2O3 nanocatalyst. α-Fe2O3 nanocatalyst with enhanced magnetic properties was synthesized. Effect of magnetic properties and morphology of α-Fe2O3 on ammonia yield was tested. α-Fe2O3 nanowires with improved saturation magnetization created high ammonia yield. A maximum green ammonia yield of 24.174xA0;×xA0;10−3xA0;molxA0;h−1xA0;gxA0;cat−1 was produced.