New organic‐pillared zincophosphate and interpenetrating‐layered zinc coordination polymer: Crystal growth on tarbuttite‐like sheets with surface‐active carboxylic acid groups

Abstract

AbstractFor the first time, crystal growth of two novel distinct structures is observed to emerge from parent tarbuttite‐like zincophosphate sheets, which feature uncoordinated carboxylic acid (─COOH) groups protruding on the surface. A prior study revealed that the ─COOH groups could be modified through mechanochemical reaction to alter the wettability of bulk solid. In this study, the modification of ─COOH groups via amidation in solutions was conducted to tune the wettability to more hydrophobic. A further study in the reactivity of the zincophosphate toward various organic amines resulted in crystal growth of two novel compounds, thereby, a 2D coordination polymer with parallel interpenetrating square lattice (sql) topology and a 3D framework of organopillared zincophosphate were discovered. Intriguing structure transformation involved disassembling and assembling of not only commonly seen molecular units but also zincophosphate polyhedra and clusters: in the former case from rare 5‐coordinate zinc to 4‐coordinate zinc, and in the latter case from original positively charged tarbuttite‐like ZnPO sheets to amine‐pillared neutral sheets composed of unique edge‐sharing Zn2N2O4(H2O)2 dimers.