Anke-Lisa Höhme

Dendritic Fibrous Nanosilica (DFNS) holds great promise for applications in various biomedical fields, CO₂ capture and conversion, catalysis, environmental remediation (or water treatment), and sensor development. While the impact of primary (linear) alcohols as co-surfactants in their synthesis has been investigated, the role of other alcohols beyond linear remains unexplored to date. In this study, we investigated the impact of different alcohols as co-surfactants on the morphology, structure, and physical properties of DFNS. We employed various primary, secondary, and tertiary alcohols, as well as diols with differing chain lengths and isomers. Significant variations in the specific surface area (S_BET) and total pore volume (V_p) were revealed across the samples, accompanied by notable morphological differences observed by scanning and transmission electron microscopy and small angle X-ray scattering. The highest S_BET and V_p values were found in samples synthesized with primary or linear alcohols, while much lower values were observed for samples synthesized with branched alcohols and diols. These findings emphasize the role of alcohols in governing the final morphology and structure of DFNS.

Accomplishing on‐demand molecular separation with a high selectivity and good permeability is very desirable for pollutant removal and chemical and pharmaceutical processing. The major challenge for sub‐10 nm filtration of particles and molecules is the fabrication of high‐performance membranes with tunable pore size and designed functionality. Here, a versatile top‐down approach is demonstrated to produce such a membrane using isoporous block copolymer membranes with well‐defined pore sizes combined with growth of metal oxide using sequential infiltration synthesis and atomic layer deposition (SIS and ALD). The pore size of the membranes is tuned by controlled metal oxide growth within and onto the polymer channels, enabling up to twofold pore diameter reduction. Following the growth, the distinct functionalities are readily incorporated along the membrane nanochannels with either hydrophobic, cationic, or anionic groups via straightforward and scalable gas/liquid–solid interface reactions. The hydrophilicity/hydrophobicity of the membrane nanochannel is significantly changed by the introduction of hydrophilic metal oxide and hydrophobic fluorinated groups. The functionalized membranes exhibit a superior selectivity and permeability in separating 1–2 nm organic molecules and fractionating similar‐sized proteins based on size, charge, and hydrophobicity. This demonstrates the great potential of organic–inorganic–organic isoporous membranes for high‐performance molecular separation in numerous applications.