Appropriate dispersants for the dispersion of gallium zinc oxide (GZO) nanopowder in the commonly used organic medium-dimethylacetamide (DMAC) are proposed by this study. The dispersion efficiencies and stabilization mechanisms of three dispersants the organic-based dispersant tris(2-butoxyethyl) phosphate (OP3) and two water-based dispersant polyethylenimines (PEIs) with different molecular weights are compared. Surprisingly, the water-based PEI polyelectrolytes exhibit greater efficiency than the organic-based OP3 for the dispersion of GZO nanopowder in the organic-based suspensions. This is because that the stabilization mechanism of GZO in the very polar DMAC is primarily related to steric repulsion rather than to electrostatic repulsion according to the theoretical and experimental analyses. (C) 2016 Elsevier B.V. All rights reserved.