High‐Quality Thin Films of UiO‐66‐NH(2) by Coordination Modulated Layer‐by‐Layer Liquid Phase Epitaxy

We report the fabrication of macroscopically and microscopically homogeneous, crack‐free metal‐organic framework (MOF) UiO‐66‐NH(2) (UiO: Universitetet i Oslo; [Zr(6)O(4)(OH)(4)(bdc‐NH(2))(6)]; bdc‐NH(2) (2−): 2‐amino‐1,4‐benzene dicarboxylate) thin films on silicon oxide surfaces. A DMF‐free, low‐temperature coordination modulated (CM), layer‐by‐layer liquid phase epitaxy (LPE) using the controlled secondary building block approach (CSA). Efficient substrate activation was determined as a key factor to obtain dense and smooth coatings by comparing UiO‐66‐NH(2) thin films grown on ozone and piranha acid‐activated substrates. Films of 2.60 μm thickness with a minimal surface roughness of 2 nm and a high sorption capacity of 3.53 mmol g(−1) MeOH (at 25 °C) were typically obtained in an 80‐cycle experiment at mild conditions (70 °C, ambient pressure).