Pillar substitution modulates CO2 affinity in “mmo” topology networks

The use of WO42− instead of CrO42− or MoO42− as an angular pillar in mmo topology nets has afforded two isostructural porous nets of formula [M(bpe)2WO4] (M = Co or Ni, bpe = 1,2-(4-pyridyl)ethene). The Ni variant, WOFOUR-1-Ni, is highly selective towards CO2 thanks to its exceptionally high isosteric heat of adsorption (Qst) of −65.5 kJ mol−1 at zero loading.