Herein, we demonstrate that by simply adjusting the concentration of ethanolamine (EA) in a Ni growth solution, the orientation of Ni nanocrystallite growth can be controlled, leading to the formation of a defect-rich nanosheet structure. This unique structure provides additional nanochannels for the enhancement of water permeability (1330 L m⁻² h⁻¹ bar⁻¹) with over 90% rejection (solute size ≥ 0.76 nm³).