Current approaches to create zirconium‐based metal–organic framework (MOF) fabric composites for catalysis, water purification, wound healing, gas sorption, and other applications often rely on toxic solvents, long reaction/post processing times, and batch methods hindering process scalability. Here, a novel mechanism was reported for rapid UiO‐66‐NH2 synthesis in common low‐boiling‐point solvents (water, ethanol, and acetic acid) and revealed acid–base chemistry promoting full linker dissolution and vapor‐based crystallization. The mechanism enabled scalable roll‐to‐roll production of mechanically resilient UiO‐66‐NH2 fabrics with superior chemical protective capability. Solvent choice and segregated spray delivery of organic linker and metal salt MOF precursor solutions allowed for rapid MOF nucleation on the fiber surface and decreased the energy and time needed for post‐processing, producing an activated composite in less than 165 min, far outpacing conventional MOF‐fabric synthesis approaches. The MOF‐fabric hydrolyzed and blocked permeation of the chemical warfare agent soman, outperforming the protection‐standard activated carbon cloth. This work presents both chemical insights into Zr‐MOF powder and fabric composite formation by a rapid, industrially relevant approach and demonstrates its practicality and affordability for high‐performing personal protective equipment.

In this work, we compare the initial growth trends of atomic layerdeposited aluminum oxide (Al 2 O 3 ) using three different Al precursors and H 2 O as the oxygen source on hydroxyl-terminated silicon (Si-OH) and hydrogenterminated silicon (Si-H) surfaces. Trimethylaluminum (TMA), triethylaluminum (TEA), and dimethylaluminum chloride (DMAC) are chosen as the Al precursors due to comparable variations between their structures. Thickness evolution obtained from in situ ellipsometry exhibits similar behavior for all three precursors with initially accelerated growth during the first cycle on the Si-OH starting surface, which then proceeds in a steady manner characteristic of atomic layer deposition (ALD). In situ Fourier transform infrared spectroscopy (FTIR) shows that at 200 °C both TEA and TMA react with above 85% of −OH ligands present on the initial Si-OH substrate and the subsequent H 2 O dose reacts with only ∼50% of the surface C−H groups, indicating incomplete removal of the methyl or ethyl ligands on the surface. Al 2 O 3 growth on the Si-H surface exhibits a delay due to the lack of surface hydroxyl groups, leading to formation of Si-Me or Si-Et groups. A lower reactivity of DMAC compared to TMA and TEA results in a lower initial selectivity fraction. The results provide vital insight into the importance of precursor selection for area-selective ALD applications and open a pathway for realizing selective Al 2 O 3 deposition based on inherent substrate selectivity.

Small-molecule inhibitors have recently been introduced for passivation during area-selective deposition (ASD). Small silanes like ( N, N-dimethylamino)trimethylsilane (DMATMS) selectively react with −OH sites on SiO2 to form a less reactive –OSi(CH3)3 terminated surface. The –OSi(CH3)3 surface termination can inhibit many atomic layer deposition (ALD) processes, including TiCl4/H2O ALD. However, the mechanisms by which ALD is inhibited and by which selectivity is eventually lost are not well understood. This study uses in situ Fourier-transform infrared spectroscopy to probe the adsorption of DMATMS on SiO2 and the subsequent reactions when the passivated surface is exposed to TiCl4/H2O ALD. The chemisorption of DMATMS on isolated –OH groups on SiO2 is shown to inhibit the reaction with TiCl4. Further, we find that starting with an inherently inhibiting H-terminated Si surface, DMATMS can also react with residual –OH groups and reduce the extent of nucleation. Finally, using Rutherford backscattering spectrometry, the effectiveness of DMATMS passivation on SiO2 and H-terminated Si is quantified during extended ALD cycle numbers. The insight into the mechanisms of passivation by DMATMS and passivation loss can enable the rational design of highly selective ASD processes by carefully matching compatible surfaces, passivating agents, and ALD precursors.

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Inherently disordered structures of carbon nitrides have hindered an atomic level tunability and understanding of their catalytic reactivity. Herein, coordination of copper cations within a crystalline carbon nitride, i.e., poly(triazine imide) or CNx, was found to yield two ordered structures for Cu-CNx wherein one or two Cu(I) cations coordinate to its intralayer N-triazine groups. The crystallites electrophoretically deposit from aqueous particle suspensions and yield current densities of ~10 to 50 mA/cm2 with a concomitant and increasing reduction of CO2 and H2O. Reduction of CO2 increases for smaller particles as mechanistic calculations reveal its catalysis mediated by two intralayer Cu atoms.