TY - JOUR A1 - Raju, Rajarshi Roy A1 - Liebig, Ferenc A1 - Klemke, Bastian A1 - Koetz, Joachim T1 - Ultralight magnetic aerogels from Janus emulsions JF - RSC Advances N2 - Magnetite containing aerogels were synthesized by freeze-drying olive oil/silicone oil-based Janus emulsion gels containing gelatin and sodium carboxymethylcellulose (NaCMC). The magnetite nanoparticles dispersed in olive oil are processed into the gel and remain in the macroporous aerogel after removing the oil components. The coexistence of macropores from the Janus droplets and mesopores from freeze-drying of the hydrogels in combination with the magnetic properties offer a special hierarchical pore structure, which is of relevance for smart supercapacitors, biosensors, and spilled oil sorption and separation. The morphology of the final structure was investigated in dependence on initial compositions. More hydrophobic aerogels with magnetic responsiveness were synthesized by bisacrylamide-crosslinking of the hydrogel. The crosslinked aerogels can be successfully used in magnetically responsive clean up experiments of the cationic dye methylene blue. Y1 - 2019 U6 - https://doi.org/10.1039/c9ra10247g SN - 2046-2069 VL - 10 IS - 13 SP - 7492 EP - 7499 PB - RSC Publishing CY - London ER - TY - GEN A1 - Liebig, Ferenc A1 - Sarhan, Radwan Mohamed A1 - Bargheer, Matias A1 - Schmitt, Clemens Nikolaus Zeno A1 - Poghosyan, Armen H. A1 - Shahinyanf, Aram A. A1 - Koetz, Joachim T1 - Spiked gold nanotriangles BT - Formation, characterization and applications in surface-enhanced Raman spectroscopy and plasmon-enhanced catalysis T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - We show the formation of metallic spikes on the surface of gold nanotriangles (AuNTs) by using the same reduction process which has been used for the synthesis of gold nanostars. We confirm that silver nitrate operates as a shape-directing agent in combination with ascorbic acid as the reducing agent and investigate the mechanism by dissecting the contribution of each component, i.e., anionic surfactant dioctyl sodium sulfosuccinate (AOT), ascorbic acid (AA), and AgNO3. Molecular dynamics (MD) simulations show that AA attaches to the AOT bilayer of nanotriangles, and covers the surface of gold clusters, which is of special relevance for the spike formation process at the AuNT surface. The surface modification goes hand in hand with a change of the optical properties. The increased thickness of the triangles and a sizeable fraction of silver atoms covering the spikes lead to a blue-shift of the intense near infrared absorption of the AuNTs. The sponge-like spiky surface increases both the surface enhanced Raman scattering (SERS) cross section of the particles and the photo-catalytic activity in comparison with the unmodified triangles, which is exemplified by the plasmon-driven dimerization of 4-nitrothiophenol (4-NTP) to 4,4'-dimercaptoazobenzene (DMAB). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 829 Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-445568 SN - 1866-8372 IS - 829 ER - TY - GEN A1 - Raju, Rajarshi Roy A1 - Liebig, Ferenc A1 - Klemke, Bastian A1 - Koetz, Joachim T1 - Ultralight magnetic aerogels from Janus emulsions T2 - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe N2 - Magnetite containing aerogels were synthesized by freeze-drying olive oil/silicone oil-based Janus emulsion gels containing gelatin and sodium carboxymethylcellulose (NaCMC). The magnetite nanoparticles dispersed in olive oil are processed into the gel and remain in the macroporous aerogel after removing the oil components. The coexistence of macropores from the Janus droplets and mesopores from freeze-drying of the hydrogels in combination with the magnetic properties offer a special hierarchical pore structure, which is of relevance for smart supercapacitors, biosensors, and spilled oil sorption and separation. The morphology of the final structure was investigated in dependence on initial compositions. More hydrophobic aerogels with magnetic responsiveness were synthesized by bisacrylamide-crosslinking of the hydrogel. The crosslinked aerogels can be successfully used in magnetically responsive clean up experiments of the cationic dye methylene blue. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 828 Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-445522 IS - 828 ER - TY - JOUR A1 - Liebig, Ferenc A1 - Sarhan, Radwan Mohamed A1 - Bargheer, Matias A1 - Schmitt, Clemens Nikolaus Zeno A1 - Poghosyan, Armen H. A1 - Shahinyanf, Aram A. A1 - Koetz, Joachim T1 - Spiked gold nanotriangles BT - Formation, characterization and applications in surface-enhanced Raman spectroscopy and plasmon-enhanced catalysis JF - RSC Advances N2 - We show the formation of metallic spikes on the surface of gold nanotriangles (AuNTs) by using the same reduction process which has been used for the synthesis of gold nanostars. We confirm that silver nitrate operates as a shape-directing agent in combination with ascorbic acid as the reducing agent and investigate the mechanism by dissecting the contribution of each component, i.e., anionic surfactant dioctyl sodium sulfosuccinate (AOT), ascorbic acid (AA), and AgNO3. Molecular dynamics (MD) simulations show that AA attaches to the AOT bilayer of nanotriangles, and covers the surface of gold clusters, which is of special relevance for the spike formation process at the AuNT surface. The surface modification goes hand in hand with a change of the optical properties. The increased thickness of the triangles and a sizeable fraction of silver atoms covering the spikes lead to a blue-shift of the intense near infrared absorption of the AuNTs. The sponge-like spiky surface increases both the surface enhanced Raman scattering (SERS) cross section of the particles and the photo-catalytic activity in comparison with the unmodified triangles, which is exemplified by the plasmon-driven dimerization of 4-nitrothiophenol (4-NTP) to 4,4'-dimercaptoazobenzene (DMAB). Y1 - 2020 U6 - https://doi.org/10.1039/d0ra00729c SN - 2046-2069 VL - 10 IS - 14 SP - 8152 EP - 8160 PB - RSC Publishing CY - London ER -