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Abstract Liquid‐like nanoparticle organic hybrid materials (NOHMs) consisting of a silica core with ionically grafted branched polyethyleneimine chains (referred to as NIPEI) are encapsulated within submicron‐scale polyacrylonitrile (PAN)/polymer‐derived‐ceramic electrospun fibers. The addition of a room‐temperature curable, liquid‐phase organopolysilazane (OPSZ) ceramic precursor to the PAN/NOHM solution enhances the internal dispersion of NOHMs and forms a thin ceramic sheath layer on the fiber exterior, shielding the hydrophilic NIPEI to produce near‐superhydrophobic non‐woven fiber mats with contact angles exceeding 140°. 60:40 loadings of NOHMs to PAN/OPSZ can be reliably achieved with low OPSZ percentages required, and up to 4:1 NOHM:polymer loadings are possible before losing hydrophobicity. These fibers demonstrate up to ≈2 mmol CO₂g⁻¹fiber capture capacities in a pure CO₂atmosphere through the nonwoven fibrous networks and the permeability of the OPSZ shell. The hybrid fibers additionally show enhanced capture kinetics under pure CO₂and 400 ppm CO₂conditions, indicating their promising application as a direct air capture platform. 

Rechargeable aluminum–graphite batteries are an emerging energy storage technology with great promise: they exhibit high rate performance, cyclability, and a discharge potential of approximately 2 V, while both electrodes are globally abundant, low cost, and inherently safe. The batteries use chloroaluminate-containing electrolytes and store charge in the graphite electrodes when molecular AlCl 4 − anions electrochemically intercalate within them. However, much remains to be understood regarding the ion intercalation mechanism, in part due to challenges associated with characterizing the chloroaluminate anions themselves. Here, we use solid-state 27 Al nuclear magnetic resonance (NMR) spectroscopy to probe the molecular-level electronic and magnetic environments of intercalated chloroaluminate anions at different states-of-charge. The results reveal broad 27 Al NMR signals associated with intercalated AlCl 4 − anions, reflecting high extents of local disorder. The intercalated anions experience a diversity of local environments, many of which are far from the ideal crystalline-like structures often depicted in graphite staging models. Density functional theory (DFT) calculations of the total 27 Al isotropic shifts enable the contributions of chemical shift, ring-current effects, and electric quadrupolar interactions to be disentangled quantitatively. In combination, the solid-state NMR and DFT results reveal the molecular geometries and environments of intercalated AlCl 4 − anions and capture the significant disorder present in intercalated graphite battery electrodes.