Effects of experimental conditions on one-dimensional single-crystal nanostructure of β-FeOOH

► One-dimensional β-FeOOH nanorods were prepared without any template. ► The aspect ratio of the sample can be adjusted from 6 to 24. ► Different electrolytes (KCl, KSCN, NaNO3, and NH4Cl) influence the sizes and structures of the samples.