Controlling the particle size and shape of soft metal-organic framework compounds is crucial for understanding and regulating the adsorption-induced structural transitions that lead to the unique stepwise adsorption behavior of these materials. The present study demonstrates that the intensive mixing facilitated by a microreactor enables the synthesis of monodisperse zeolitic imidazolate framework-8 (ZIF-8) particles with high reproducibility. In the flow microreactor process used in this study, the particle size is predominantly determined by the reaction conditions during the initial mixing in the mictoreactor. On the other hand, the particle shape depends upon the temperature during the subsequent aging process. The technique proposed in this study is additive-free and allows control of both particle size from 50 nm to 2 mu m and particle shape from cube to chamfered cube to rhombic dodecahedron, simply by adjusting the concentration of feed solutions and reaction temperature. Furthermore, we demonstrate that both particle size and particle shape are key physical parameters determining the adsorption characteristics of ZIF-8 particles. (C) 2016 Elsevier B.V. All rights reserved.