DAC refers to the direct removal of CO 2 from the atmosphere, that is at its ambient ultradilute concentration of ca. 400 ppm (or 0.04 %). Negative emissions technologies-which include both DAC and indirect air capture approaches-have been identified in the Paris Climate Accords as a necessary component of limiting the rise in global temperature to 1.5 • C by the year 2100. Given the urgency of the problem, commercial DAC projects are now underway utilizing the reactivity of amine solutions and aqueous alkali hydroxides. Nonetheless, widespread adoption of DAC is still constrained by the high price of $600-1000 per tonne of CO 2 removed. Reductions in cost required for gigatonne deployment are anticipated to come from optimized plant designs, efficiency improvements associated with scale-up, and, perhaps most importantly, more effective chemical sorbents (i.e. the material responsible for the capture). Understandably there has been increasing fundamental research into novel materials with high CO 2 capture capacities, favorable kinetics, low energy regeneration procedures, and long lifetimes. Some inorganic compounds containing metal centers and O 2 ligands have been known to exhibit DAC-like chemistry. Early experimental work on the dimeric peroxovanadate K