Publications

@article{Yin2020a,
title = {Key Factors for Template-Oriented Porous Titania Synthesis: Solvents and Catalysts},
author = {Shanshan Yin and Lin Song and Senlin Xia and Yajun Cheng and Nuri Hohn and Wei Chen and Kun Wang and Wei Cao and Shujin Hou and Peter Müller-Buschbaum},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/smtd.201900689},
doi = {https://doi.org/10.1002/smtd.201900689},
year = {2020},
date = {2020-01-01},
journal = {Small Methods},
volume = {4},
number = {3},
pages = {1900689},
abstract = {Abstract Various types of titania nanostructures are synthesized with a polymer-templated sol–gel method based on the amphiphilic diblock copolymer polystyrene-b-polyethylene oxide (PS-b-PEO) in combination with selective incorporation of the titania precursor titanium tetraisopropoxide. Custom tailoring of different types of titania morphologies is realized by changing the phase separation behavior of the PS-b-PEO template. Particularly, application of solvents from different categories is found to have a major impact upon the phase separation behavior of PS-b-PEO and the final titania film morphology. The amount of available hydrochloric acid catalyst during the gelation process is seen as an additional key factor to induce controllable morphological changes. Scanning electron microscopy and grazing incidence small angle X-ray scattering measurements are carried out to study the surface and inner structure of porous titania films. Systematic analysis and comparison of different characterization results allow attributing the following three factors to the respectively formed titania nanostructure: the surface energy between PS blocks and surrounding solvent, the aggregation behavior of the titania nanoparticles, and the block-specific selectivity of the used solvent. For all synthesized titania thin films, an anatase-type crystallization is confirmed through X-ray powder diffraction.},
keywords = {GISAXS, morphology, nanostructures, sol–gel synthesis, titania},
pubstate = {published},
tppubtype = {article}
}

@article{Maehringerb,
title = {Energy Efficient Ultrahigh Flux Separation of Oily Pollutants from Water with Superhydrophilic Nanoscale Metal–Organic Framework Architectures},
author = {Andre Mähringer and Matthias Hennemann and Timothy Clark and Thomas Bein and Dana D Medina},
url = {https://onlinelibrary.wiley.com/doi/abs/10.1002/anie.202012428},
doi = {https://doi.org/10.1002/anie.202012428},
journal = {Angewandte Chemie International Edition},
volume = {n/a},
number = {n/a},
abstract = {Abstract The rising demand for clean water for a growing and increasingly urban global population is one of the most urgent issues of our time. Here, we introduce the synthesis of a unique nanoscale architecture of pillar-like Co-CAT-1 metal–organic framework (MOF) crystallites on gold-coated woven stainless steel meshes with large, 50 μm apertures. These nanostructured mesh surfaces feature superhydrophilic and underwater superoleophobic wetting properties, allowing for gravity-driven, highly efficient oil–water separation featuring water fluxes of up to nearly one million L m−2 h−1. Water physisorption experiments reveal the hydrophilic nature of Co-CAT-1 with a total water vapor uptake at room temperature of 470 cm3 g−1. Semiempirical molecular orbital calculations shed light on water affinity of the inner and outer pore surfaces. The MOF-based membranes enable high separation efficiencies for a number of liquids tested, including the notorious water pollutant, crude oil, affording chemical oxygen demand (COD) concentrations below 25 mg L−1 of the effluent. Our results demonstrate the great impact of suitable nanoscale surface architectures as a means of encoding on-surface extreme wetting properties, yielding energy-efficient water-selective large-aperture membranes.},
keywords = {nanostructures, surface chemistry, thin films, vapor-assisted conversion},
pubstate = {published},
tppubtype = {article}
}