Construction of a robust yttrium-hydroxamate metal–organic framework for H2O adsorption†

A robust yttrium-hydroxamate metal–organic framework (MOF) was successfully prepared via solvothermal synthesis, as a new addition to the burgeoning category of hydroxamate-based MOFs. The Y-MOF, namely SUM-92, exhibits exceptional chemical stability across a wide pH range of 2 to 13 and thermal stability up to approx. 320 °C, as a result of the interconnection of one-dimensional infinite Y-oxo building blocks by chelating hydroxamate linkers. Moreover, the incorporation of pyrazine moieties in SUM-92 significantly enhanced the MOF's hydrophilicity, with crystallinity retained. SUM-92 demonstrated an uptake of 0.27 g g⁻¹ during water vapor adsorption and an inflection point of ∼23% relative humidity on the isotherm. This work furthers the integration of hydroxamate chemistry with MOF materials, and the exploration of the application range for the products thereof.