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Metal-ion-containing soft materials include metallogels, metal-organic frameworks, and coordination polymers. These materials show commercial value in catalysis, hydrogen storage, and electronics. Metal-containing soft materials reported to date are structurally weak, falling short of a Young’s modulus typical of engineering-grade materials. We report herein that inclusion of an antisolvent in metal-thiolate metallogel synthesis results in a colloidal sol, where the colloids comprise amorphous metal-organic complexes. Upon desolvation, the colloids coalesce to form a solid phase that is both gel like and glass like. This solid phase is structurally amorphous, comprises continuous networks similar to organic polymers, and has stiffness observed in polymeric materials with extended structure, yet contains a superstoichiometric amount of metal relative to organic ligand. The solid phase is therefore a rigid, amorphous metal-rich (RAMETRIC) material. Highlighting the rigidity, the Young’s modulus of the gel-phase material is 1,000× greater than metallogels comprised of the same constituent building blocks. 

Abstract Midlatitude surface meteorological conditions are embedded within—and affected by—synoptic‐scale systems, including the movement and persistence of air masses (AMs). Changes in AM frequencies (number of daily occurrences) over the past several decades could have large effects on ecosystems: each organism is exposed to the synergistic effects of the entire suite of atmospheric variables acting upon it—an inherently multivariate environment—which is best captured using AMs. Utilizing a global‐scale AM classification system and a large network of tree‐ring chronologies, we investigate how variation in AM frequency impacts tree growth at over 900 locations. We find that AM frequencies are well‐correlated with tree growth, especially in the 12‐month period from July in the year prior to growth through June in the year of growth. The most impactful AMs are Dry‐Warm and Humid‐Cool AMs, which exhibit average correlations ofρ = −0.4 andρ = +0.4 with tree growth, respectively, for certain tree species, with correlations at some sites exceedingρ =  ±0.8 in some seasons. Compared to empirical models based solely on temperature and precipitation, modeling using only AM frequencies proved superior at nearly 60% of the sites and for over 80% of the well‐sampled (n ≥ 10) species. These results should provide a foundation for using AMs to improve forecasts of tree growth, tree stress and wildfire potential. Long‐term reconstructions of AM frequencies back several centuries may also be feasible using tree‐ring data, which will help contextualize and temporally extend multivariate perspectives of climate change that utilize such air masses. 

Controlling the 3-D morphology of nanocatalysts is one of the underexplored but important approaches for improving the sluggish kinetics of the oxygen evolution reaction (OER) in water electrolysis. This work reports a scalable, oil-based method based on thermal decomposition of organometallic complexes to yield highly uniform Ni–Fe-based nanocatalysts with a well-defined morphology ( i.e. Ni–Fe core–shell, Ni/Fe alloy, and Fe–Ni core–shell). Transmission electron microscopy reveals their morphology and composition to be NiO x –FeO x /NiO x core-mixed shell, NiO x /FeO x alloy, and FeO x –NiO x core–shell. X-ray techniques resolve the electronic structures of the bulk and are supported by electron energy loss spectroscopy analysis of individual nanoparticles. These results suggest that the crystal structure of Ni is most likely to contain α-Ni(OH) 2 and that the chemical environment of Fe is variable, depending on the morphology of the nanoparticle. The Ni diffusion from the amorphous Ni-based core to the iron oxide shell makes the NiO x –NiO x /FeO x core-mixed shell structure the most active and the most stable nanocatalyst, which outperforms the comparison NiO x /FeO x alloy nanoparticles expected to be active for the OER. This study suggests that the chemical environment of the mixed NiO x /FeO x alloy composition is important to achieve high electrocatalytic activity for the OER and that the 3-D morphology plays a key role in the optimization of the electrocatalytic activity and stability of the nanocatalyst for the OER.