Maged F. Bekheet

The development of magnesium ion batteries as a viable alternative to lithium–ion batteries is impeded by the lack of efficient and stable electrode materials. Here, we present the synthesis of nanocomposites of tin–containing silicon oxycarbonitride (Sn/SiOCN) as anode materials for magnesium ion batteries (MIBs). The elemental and phase composition, morphology, and surface area of the nanocomposites are assessed by several characterization techniques. The galvanostatic cycling tests indicate a substantial initial discharging capacity for the anode with 42.2 wt . % of tin. Specifically, the first discharging capacities are 489.9 mA/g, 172.9 mA/g, and 136.6 mA/g at current densities of 0.5 mA/g, 50 mA/g, and 500 mA/g, respectively. After 100 cycles at a current density of 500 mA/g, the anode containing 33.8 wt % of tin exhibits a reversible capacity of 101.8 mAh/g and a remarkable rate performance efficiency of 76.5 %. Increasing tin content in the electrode materials increases the battery performance by decreasing electrode impedance and thus facilitating Mg 2+ diffusion, as revealed by electrochemical impedance spectroscopy (EIS). Ex situ XRD and X‐ray photoelectron spectroscopy (XPS) characterizations following the magnesiation–demagnesiation process confirm the storage of reversible storage of Mg 2+ ions in Sn/SiOCN electrode through incorporation in the SiOCN network and alloying/dealloying process involving Mg−Mg 2 Sn−Mg.

Hierarchically porous, high‐surface‐area silica materials are excellent candidates for multiple applications like catalysis and environmental remediation. Shaping these materials with additive manufacturing (AM) techniques, like robocasting, could enable their use with the benefit of on‐demand, customized shaping and maximizing performance. Herein, ordered mesoporous silica COK‐12 slurries were robocasted into monoliths, containing different ratios of uncalcined COK‐12 and sodium bentonite (0–25 wt.%). The rheology of the mixed slurries is characterized by lower flow indexes (0.69 vs. 0.32) and higher yield stresses (96 vs. 259 Pa) compared to pure COK‐12 ones. Monoliths were printed in woodpile structures and calcined at 600°C. Micro‐CT measurements showed a linear shrinkage of 25% after calcination. Mechanical characterization showed increased uniaxial strength (0.20 ± 0.07 to 1.0 ± 0.3 MPa) with increasing binder/solids ratio from 13 to 25%. The amorphous, mesoporous structure of COK‐12 was retained. The structures exhibited open porosities of 52 ± 4% and showed higher specific mesopore volumes, and increased average mesopore size (6 vs. 8 nm) compared to COK‐12. Small‐angle x‐ray scattering analysis revealed an increased lattice parameter (10.3 vs. 11.0 nm) and reduced wall thickness (3.1 nm vs. 4.1 nm) of the COK‐12 in the monoliths. These properties indicate suitability for their application as porous supports and adsorbents.