TY - GEN A1 - Bhattacharyya, Biswajit A1 - Balischewski, Christian A1 - Sperlich, Eric A1 - Günter, Christina A1 - Mies, Stefan A1 - Kelling, Alexandra A1 - Taubert, Andreas T1 - N-Butyl Pyridinium Diiodido Argentate(I) BT - A One-Dimensional Ag-I Network with Superior Solid-State Ionic Conductivity at Room Temperature T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1341 KW - AgI KW - ionic conductivity KW - Ionic liquids KW - thermal properties Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-604874 SN - 1866-8372 IS - 1341 ER - TY - JOUR A1 - Bhattacharyya, Biswajit A1 - Balischewski, Christian A1 - Sperlich, Eric A1 - Günter, Christina A1 - Mies, Stefan A1 - Kelling, Alexandra A1 - Taubert, Andreas T1 - N-Butyl Pyridinium Diiodido Argentate(I) BT - A One-Dimensional Ag-I Network with Superior Solid-State Ionic Conductivity at Room Temperature JF - Advanced materials interfaces N2 - A new solid-state material, N-butyl pyridinium diiodido argentate(I), is synthesized using a simple and effective one-pot approach. In the solid state, the compound exhibits 1D ([AgI2](-))(n) chains that are stabilized by the N-butyl pyridinium cation. The 1D structure is further manifested by the formation of long, needle-like crystals, as revealed from electron microscopy. As the general composition is derived from metal halide-based ionic liquids, the compound has a low melting point of 100-101 degrees C, as confirmed by differential scanning calorimetry. Most importantly, the compound has a conductivity of 10(-6) S cm(-1) at room temperature. At higher temperatures the conductivity increases and reaches to 10(-4 )S cm(-1) at 70 degrees C. In contrast to AgI, however, the current material has a highly anisotropic 1D arrangement of the ionic domains. This provides direct and tuneable access to fast and anisotropic ionic conduction. The material is thus a significant step forward beyond current ion conductors and a highly promising prototype for the rational design of highly conductive ionic solid-state conductors for battery or solar cell applications. KW - AgI KW - ionic conductivity KW - Ionic liquids KW - thermal properties Y1 - 2023 U6 - https://doi.org/10.1002/admi.202202363 SN - 2196-7350 VL - 10 IS - 12 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Adesina, Morenike O. A1 - Block, Inga A1 - Günter, Christina A1 - Unuabonah, Emmanuel Iyayi A1 - Taubert, Andreas T1 - Efficient Removal of Tetracycline and Bisphenol A from Water with a New Hybrid Clay/TiO2 Composite JF - ACS Omega N2 - New TiO2 hybrid composites were prepared fromkaolinclay, predried and carbonized biomass, and titanium tetraisopropoxideand explored for tetracycline (TET) and bisphenol A (BPA) removalfrom water. Overall, the removal rate is 84% for TET and 51% for BPA.The maximum adsorption capacities (q (m))are 30 and 23 mg/g for TET and BPA, respectively. These capacitiesare far greater than those obtained for unmodified TiO2. Increasing the ionic strength of the solution does not change theadsorption capacity of the adsorbent. pH changes only slightly changeBPA adsorption, while a pH > 7 significantly reduces the adsorptionof TET on the material. The Brouers-Sotolongo fractal modelbest describes the kinetic data for both TET and BPA adsorption, predictingthat the adsorption process occurs via a complex mechanism involvingvarious forces of attraction. Temkin and Freundlich isotherms, whichbest fit the equilibrium adsorption data for TET and BPA, respectively,suggest that adsorption sites are heterogeneous in nature. Overall,the composite materials are much more effective for TET removal fromaqueous solution than for BPA. This phenomenon is assigned to a differencein the TET/adsorbent interactions vs the BPA/adsorbent interactions:the decisive factor appears to be favorable electrostatic interactionsfor TET yielding a more effective TET removal. Y1 - 2023 U6 - https://doi.org/10.1021/acsomega.3c00184 SN - 2470-1343 VL - 8 IS - 24 SP - 21594 EP - 21604 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Kim, Jiyong A1 - Kim, Yohan A1 - Park, Kyoungwon A1 - Boeffel, Christine A1 - Choi, Hyung-Seok A1 - Taubert, Andreas A1 - Wedel, Armin T1 - Ligand Effect in 1-Octanethiol Passivation of InP/ZnSe/ZnS Quantum Dots-Evidence of Incomplete Surface Passivation during Synthesis JF - Small : nano micro N2 - The lack of anionic carboxylate ligands on the surface of InP/ZnSe/ZnS quantum dots (QDs), where zinc carboxylate ligands can be converted to carboxylic acid or carboxylate ligands via proton transfer by 1-octanethiol, is demonstrated. The as-synthesized QDs initially have an under-coordinated vacancy surface, which is passivated by solvent ligands such as ethanol and acetone. Upon exposure of 1-octanethiol to the QD surface, 1-octanethiol effectively induces the surface binding of anionic carboxylate ligands (derived from zinc carboxylate ligands) by proton transfer, which consequently exchanges ethanol and acetone ligands that bind on the incomplete QD surface. These systematic chemical analyses, such as thermogravimetric analysis-mass spectrometry and proton nuclear magnetic resonance spectroscopy, directly show the interplay of surface ligands, and it associates with QD light-emitting diodes (QD-LEDs). It is believed that this better understanding can lead to industrially feasible QD-LEDs. KW - colloidal quantum dots KW - incomplete surface passivation KW - indium KW - phosphide KW - surface chemistry KW - thiol passivation Y1 - 2022 U6 - https://doi.org/10.1002/smll.202203093 SN - 1613-6810 SN - 1613-6829 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - Behrens, Karsten A1 - Balischewski, Christian A1 - Sperlich, Eric A1 - Menski, Antonia Isabell A1 - Balderas-Valadez, Ruth Fabiola A1 - Pacholski, Claudia A1 - Günter, Christina A1 - Lubahn, Susanne A1 - Kelling, Alexandra A1 - Taubert, Andreas T1 - Mixed chloridometallate(ii) ionic liquids with tunable color and optical response for potential ammonia sensors T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1316 Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-587512 SN - 1866-8372 IS - 1316 SP - 35072 EP - 35082 ER - TY - JOUR A1 - Figueroa Campos, Gustavo Adolfo A1 - G. K. T. Kruizenga, Johannes A1 - Sagu Tchewonpi, Sorel A1 - Schwarz, Steffen A1 - Homann, Thomas A1 - Taubert, Andreas A1 - Rawel, Harshadrai Manilal T1 - Effect of the post-harvest processing on protein modification in green coffee beans by phenolic compounds JF - Foods : open access journal N2 - The protein fraction, important for coffee cup quality, is modified during post-harvest treatment prior to roasting. Proteins may interact with phenolic compounds, which constitute the major metabolites of coffee, where the processing affects these interactions. This allows the hypothesis that the proteins are denatured and modified via enzymatic and/or redox activation steps. The present study was initiated to encompass changes in the protein fraction. The investigations were limited to major storage protein of green coffee beans. Fourteen Coffea arabica samples from various processing methods and countries were used. Different extraction protocols were compared to maintain the status quo of the protein modification. The extracts contained about 4–8 µg of chlorogenic acid derivatives per mg of extracted protein. High-resolution chromatography with multiple reaction monitoring was used to detect lysine modifications in the coffee protein. Marker peptides were allocated for the storage protein of the coffee beans. Among these, the modified peptides K.FFLANGPQQGGK.E and R.LGGK.T of the α-chain and R.ITTVNSQK.I and K.VFDDEVK.Q of β-chain were detected. Results showed a significant increase (p < 0.05) of modified peptides from wet processed green beans as compared to the dry ones. The present study contributes to a better understanding of the influence of the different processing methods on protein quality and its role in the scope of coffee cup quality and aroma. View Full-Text KW - Arabica coffee KW - coffee processing KW - protein modification KW - bound phenolic compounds KW - peptide biomarkers KW - LC-MS/MS Y1 - 2022 U6 - https://doi.org/10.3390/foods11020159 SN - 2304-8158 VL - 11 PB - MDPI CY - Basel, Schweiz ET - 2 ER - TY - JOUR A1 - Behrens, Karsten A1 - Balischewski, Christian A1 - Sperlich, Eric A1 - Menski, Antonia Isabell A1 - Balderas-Valadez, Ruth Fabiola A1 - Pacholski, Claudia A1 - Günter, Christina A1 - Lubahn, Susanne A1 - Kelling, Alexandra A1 - Taubert, Andreas T1 - Mixed chloridometallate(ii) ionic liquids with tunable color and optical response for potential ammonia sensors JF - RSC Advances N2 - Eight d-metal-containing N-butylpyridinium ionic liquids (ILs) with the nominal composition (C4Py)2[Ni0.5M0.5Cl4] or (C4Py)2[Zn0.5M0.5Cl4] (M = Cu, Co, Mn, Ni, Zn; C4Py = N-butylpyridinium) were synthesized, characterized, and investigated for their optical properties. Single crystal and powder X-ray analysis shows that the compounds are isostructural to existing examples based on other d-metal ions. Inductively coupled plasma optical emission spectroscopy measurements confirm that the metal/metal ratio is around 50 : 50. UV-Vis spectroscopy shows that the optical absorption can be tuned by selection of the constituent metals. Moreover, the compounds can act as an optical sensor for the detection of gases such as ammonia as demonstrated via a simple prototype setup. Y1 - 2022 U6 - https://doi.org/10.1039/d2ra05581c SN - 2046-2069 VL - 12 SP - 35072 EP - 35082 PB - RSC CY - London ER - TY - JOUR A1 - Kapernaum, Nadia A1 - Lange, Alyna A1 - Ebert, Max A1 - Grunwald, Marco A. A1 - Häge, Christian A1 - Marino, Sebastian A1 - Zens, Anna A1 - Taubert, Andreas A1 - Gießelmann, Frank A1 - Laschat, Sabine T1 - Current topics in ionic liquid crystals JF - ChemPlusChem N2 - Ionic liquid crystals (ILCs), that is, ionic liquids exhibiting mesomorphism, liquid crystalline phases, and anisotropic properties, have received intense attention in the past years. Among others, this is due to their special properties arising from the combination of properties stemming from ionic liquids and from liquid crystalline arrangements. Besides interesting fundamental aspects, ILCs have been claimed to have tremendous application potential that again arises from the combination of properties and architectures that are not accessible otherwise, or at least not accessible easily by other strategies. The current review highlights recent developments in ILC research, starting with some key fundamental aspects. Further subjects covered include the synthesis and variations of modern ILCs, including the specific tuning of their mesomorphic behavior. The review concludes with reflections on some applications that may be within reach for ILCs and finally highlights a few key challenges that must be overcome prior and during true commercialization of ILCs. KW - electrochemistry KW - ionic liquid crystals KW - mesogen mesophases KW - self-assembly KW - X-ray diffraction Y1 - 2021 U6 - https://doi.org/10.1002/cplu.202100397 SN - 2192-6506 VL - 87 IS - 1 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Balischewski, Christian A1 - Bhattacharyya, Biswajit A1 - Sperlich, Eric A1 - Günter, Christina A1 - Beqiraj, Alkit A1 - Klamroth, Tillmann A1 - Behrens, Karsten A1 - Mies, Stefan A1 - Kelling, Alexandra A1 - Lubahn, Susanne A1 - Holtzheimer, Lea A1 - Nitschke, Anne A1 - Taubert, Andreas T1 - Tetrahalidometallate(II) ionic liquids with more than one metal BT - the effect of bromide versus chloride JF - Chemistry - a European journal N2 - Fifteen N-butylpyridinium salts - five monometallic [C4Py](2)[MBr4] and ten bimetallic [C4Py](2)[(M0.5M0.5Br4)-M-a-Br-b] (M=Co, Cu, Mn, Ni, Zn) - were synthesized, and their structures and thermal and electrochemical properties were studied. All the compounds are ionic liquids (ILs) with melting points between 64 and 101 degrees C. Powder and single-crystal X-ray diffraction show that all ILs are isostructural. The electrochemical stability windows of the ILs are between 2 and 3 V. The conductivities at room temperature are between 10(-5) and 10(-6) S cm(-1). At elevated temperatures, the conductivities reach up to 10(-4) S cm(-1) at 70 degrees C. The structures and properties of the current bromide-based ILs were also compared with those of previous examples using chloride ligands, which illustrated differences and similarities between the two groups of ILs. KW - electrochemistry KW - ionic liquids KW - metal-containing ionic liquids; KW - N-butylpyridinium bromide KW - tetrahalidometallates Y1 - 2022 U6 - https://doi.org/10.1002/chem.202201068 SN - 1521-3765 VL - 28 IS - 64 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Pan, Xuefeng A1 - Sarhan, Radwan Mohamed A1 - Kochovski, Zdravko A1 - Chen, Guosong A1 - Taubert, Andreas A1 - Mei, Shilin A1 - Lu, Yan T1 - Template synthesis of dual-functional porous MoS2 nanoparticles with photothermal conversion and catalytic properties JF - Nanoscale N2 - Advanced catalysis triggered by photothermal conversion effects has aroused increasing interest due to its huge potential in environmental purification. In this work, we developed a novel approach to the fast degradation of 4-nitrophenol (4-Nip) using porous MoS2 nanoparticles as catalysts, which integrate the intrinsic catalytic property of MoS2 with its photothermal conversion capability. Using assembled polystyrene-b-poly(2-vinylpyridine) block copolymers as soft templates, various MoS 2 particles were prepared, which exhibited tailored morphologies (e.g., pomegranate-like, hollow, and open porous structures). The photothermal conversion performance of these featured particles was compared under near-infrared (NIR) light irradiation. Intriguingly, when these porous MoS2 particles were further employed as catalysts for the reduction of 4-Nip, the reaction rate constant was increased by a factor of 1.5 under NIR illumination. We attribute this catalytic enhancement to the open porous architecture and light-to-heat conversion performance of the MoS2 particles. This contribution offers new opportunities for efficient photothermal-assisted catalysis. Y1 - 2022 U6 - https://doi.org/10.1039/d2nr01040b SN - 2040-3372 VL - 14 IS - 18 SP - 6888 EP - 6901 PB - RSC Publ. (Royal Society of Chemistry) CY - Cambridge ER - TY - JOUR A1 - Abdou, Nicole A1 - Alonso, Bruno A1 - Brun, Nicolas A1 - Landois, Perine A1 - Taubert, Andreas A1 - Hesemann, Peter A1 - Mehdi, Ahmad T1 - Ionic guest in ionic host BT - ionosilica ionogel composites via ionic liquid confinement in ionosilica supports JF - Materials chemistry frontiers N2 - Ionosilica ionogels, i.e. composites consisting of an ionic liquid (IL) guest confined in an ionosilica host matrix, were synthesized via a non-hydrolytic sol-gel procedure from a tris-trialcoxysilylated amine precursor using the IL [BMIM]NTf2 as solvent. Various ionosilica ionogels were prepared starting from variable volumes of IL in the presence of formic acid. The resulting brittle and nearly colourless monoliths are composed of different amounts of IL guests confined in an ionosilica host as evidenced via thermogravimetric analysis, FT-IR, and C-13 CP-MAS solid-state NMR spectroscopy. In the following, we focused on confinement effects between the ionic host and guest. Special host-guest interactions between the IL guest and the ionosilica host were evidenced by H-1 solid-state NMR, Raman spectroscopy, and broadband dielectric spectroscopy (BDS) measurements. The three techniques indicate a strongly reduced ion mobility in the ionosilica ionogel composites containing small volume fractions of confined IL, compared to conventional silica-based ionogels. We conclude that the ionic ionosilica host stabilizes an IL layer on the host surface; this then results in a strongly reduced ion mobility compared to conventional silica hosts. The ion mobility progressively increases for systems containing higher volume fractions of IL and finally reaches the values observed in conventional silica based ionogels. These results therefore point towards strong interactions and confinement effects between the ionic host and the ionic guest on the ionosilica surface. Furthermore, this approach allows confining high volume fractions of IL into self-standing monoliths while preserving high ionic conductivity. These effects may be of interest in domains where IL phases must be anchored on solid supports to avoid leaching or IL spilling, e.g., in catalysis, in gas separation/sequestration devices or for the elaboration of solid electrolytes for (lithium-ion) batteries and supercapacitors. Y1 - 2022 U6 - https://doi.org/10.1039/d2qm00021k SN - 2052-1537 VL - 6 IS - 7 SP - 939 EP - 947 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Ihlenburg, Ramona A1 - Mai, Tobias A1 - Thünemann, Andreas F. A1 - Baerenwald, Ruth A1 - Saalwächter, Kay A1 - Koetz, Joachim A1 - Taubert, Andreas T1 - Sulfobetaine hydrogels with a complex multilength-scale hierarchical structure JF - The journal of physical chemistry : B, Condensed matter, materials, surfaces, interfaces & biophysical chemistry N2 - Hydrogels with a hierarchical structure were prepared from a new highly water-soluble crosslinker N,N,N',N'-tetramethyl-N,N'-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and from the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The free radical polymerization of the two compounds is rapid and yields near-transparent hydrogels with sizes up to 5 cm in diameter. Rheology shows a clear correlation between the monomer-to-crosslinker ratio and the storage and loss moduli of the hydrogels. Cryo-scanning electron microscopy, low-field nuclear magnetic resonance (NMR) spectroscopy, and small-angle X-ray scattering show that the gels have a hierarchical structure with features spanning the nanometer to the sub-millimeter scale. The NMR study is challenged by the marked inhomogeneity of the gels and the complex chemical structure of the sulfobetaine monomer. NMR spectroscopy shows how these complications can be addressed via a novel fitting approach that considers the mobility gradient along the side chain of methacrylate-based monomers. KW - Defects KW - Hydrogels KW - Nuclear magnetic resonance spectroscopy KW - Scattering KW - X-ray scattering Y1 - 2021 U6 - https://doi.org/10.1021/acs.jpcb.0c10601 SN - 1520-6106 SN - 1520-5207 VL - 125 IS - 13 SP - 3398 EP - 3408 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Ihlenburg, Ramona A1 - Lehnen, Anne-Catherine A1 - Koetz, Joachim A1 - Taubert, Andreas T1 - Sulfobetaine Cryogels for Preferential Adsorption of Methyl Orange from Mixed Dye Solutions JF - Polymers / Molecular Diversity Preservation International N2 - New cryogels for selective dye removal from aqueous solution were prepared by free radical polymerization from the highly water-soluble crosslinker N,N,N’,N’-tetramethyl-N,N’-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The resulting white and opaque cryogels have micrometer sized pores with a smaller substructure. They adsorb methyl orange (MO) but not methylene blue (MB) from aqueous solution. Mixtures of MO and MB can be separated through selective adsorption of the MO to the cryogels while the MB remains in solution. The resulting cryogels are thus candidates for the removal of hazardous organic substances, as exemplified by MO and MB, from water. Clearly, it is possible that the cryogels are also potentially interesting for removal of other compounds such as pharmaceuticals or pesticides, but this must be investigated further. KW - cryogel KW - water treatment KW - dye removal KW - methyl orange KW - methylene blue KW - dye mixture Y1 - 2020 U6 - https://doi.org/10.3390/polym13020208 SN - 2073-4360 VL - 13 IS - 2 PB - MDPI CY - Basel ER - TY - GEN A1 - Ihlenburg, Ramona A1 - Lehnen, Anne-Catherine A1 - Koetz, Joachim A1 - Taubert, Andreas T1 - Sulfobetaine Cryogels for Preferential Adsorption of Methyl Orange from Mixed Dye Solutions T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - New cryogels for selective dye removal from aqueous solution were prepared by free radical polymerization from the highly water-soluble crosslinker N,N,N’,N’-tetramethyl-N,N’-bis(2-ethylmethacrylate)-propyl-1,3-diammonium dibromide and the sulfobetaine monomer 2-(N-3-sulfopropyl-N,N-dimethyl ammonium)ethyl methacrylate. The resulting white and opaque cryogels have micrometer sized pores with a smaller substructure. They adsorb methyl orange (MO) but not methylene blue (MB) from aqueous solution. Mixtures of MO and MB can be separated through selective adsorption of the MO to the cryogels while the MB remains in solution. The resulting cryogels are thus candidates for the removal of hazardous organic substances, as exemplified by MO and MB, from water. Clearly, it is possible that the cryogels are also potentially interesting for removal of other compounds such as pharmaceuticals or pesticides, but this must be investigated further. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1093 KW - cryogel KW - water treatment KW - dye removal KW - methyl orange KW - methylene blue KW - dye mixture Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-488987 SN - 1866-8372 IS - 1093 ER - TY - GEN A1 - Block, Inga A1 - Günter, Christina A1 - Rodrigues, Alysson Duarte A1 - Paasch, Silvia A1 - Hesemann, Peter A1 - Taubert, Andreas T1 - Carbon Adsorbents from Spent Coffee for Removal of Methylene Blue and Methyl Orange from Water T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Activated carbons (ACs) were prepared from dried spent coffee (SCD), a biological waste product, to produce adsorbents for methylene blue (MB) and methyl orange (MO) from aqueous solution. Pre-pyrolysis activation of SCD was achieved via treatment of the SCD with aqueous sodium hydroxide solutions at 90 °C. Pyrolysis of the pretreated SCD at 500 °C for 1 h produced powders with typical characteristics of AC suitable and effective for dye adsorption. As an alternative to the rather harsh base treatment, calcium carbonate powder, a very common and abundant resource, was also studied as an activator. Mixtures of SCD and CaCO3 (1:1 w/w) yielded effective ACs for MO and MB removal upon pyrolysis needing only small amounts of AC to clear the solutions. A selectivity of the adsorption process toward anionic (MO) or cationic (MB) dyes was not observed. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1155 KW - water KW - spent coffee KW - dye adsorption KW - methylene blue KW - methyl orange KW - calcium carbonate KW - activated carbon KW - water treatment KW - dye removal Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-521653 SN - 1866-8372 IS - 14 ER - TY - JOUR A1 - Block, Inga A1 - Günter, Christina A1 - Rodrigues, Alysson Duarte A1 - Paasch, Silvia A1 - Hesemann, Peter A1 - Taubert, Andreas T1 - Carbon Adsorbents from Spent Coffee for Removal of Methylene Blue and Methyl Orange from Water JF - Materials N2 - Activated carbons (ACs) were prepared from dried spent coffee (SCD), a biological waste product, to produce adsorbents for methylene blue (MB) and methyl orange (MO) from aqueous solution. Pre-pyrolysis activation of SCD was achieved via treatment of the SCD with aqueous sodium hydroxide solutions at 90 °C. Pyrolysis of the pretreated SCD at 500 °C for 1 h produced powders with typical characteristics of AC suitable and effective for dye adsorption. As an alternative to the rather harsh base treatment, calcium carbonate powder, a very common and abundant resource, was also studied as an activator. Mixtures of SCD and CaCO3 (1:1 w/w) yielded effective ACs for MO and MB removal upon pyrolysis needing only small amounts of AC to clear the solutions. A selectivity of the adsorption process toward anionic (MO) or cationic (MB) dyes was not observed. KW - water KW - spent coffee KW - dye adsorption KW - methylene blue KW - methyl orange KW - calcium carbonate KW - activated carbon KW - water treatment KW - dye removal Y1 - 2021 U6 - https://doi.org/10.3390/ma14143996 SN - 1996-1944 VL - 14 IS - 14 PB - MDPI CY - Basel ER - TY - JOUR A1 - Wojnarowska, Zaneta A1 - Lange, Alyna A1 - Taubert, Andreas A1 - Paluch, Marian T1 - Ion and proton transport in aqueous/nonaqueous acidic tonic liquids for fuel-cell applications-insight from high-pressure dielectric studies JF - ACS applied materials & interfaces / American Chemical Society N2 - The use of acidic ionic liquids and solids as electrolytes in fuel cells is an emerging field due to their efficient proton conductivity and good thermal stability. Despite multiple reports describing conducting properties of acidic ILs, little is known on the charge-transport mechanism in the vicinity of liquid-glass transition and the structural factors governing the proton hopping. To address these issues, we studied two acidic imidazolium-based ILs with the same cation, however, different anions-bulk tosylate vs small methanesulfonate. High-pressure dielectric studies of anhydrous and water-saturated materials performed in the close vicinity of T-g have revealed significant differences in the charge-transport mechanism in these two systems being undetectable at ambient conditions. Thereby, we demonstrated the effect of molecular architecture on proton hopping, being crucial in the potential electrochemical applications of acidic ILs. KW - proton hopping KW - dielectric spectroscopy KW - high pressure KW - ion transport KW - acidic ionic liquids Y1 - 2021 U6 - https://doi.org/10.1021/acsami.1c06260 SN - 1944-8244 SN - 1944-8252 VL - 13 IS - 26 SP - 30614 EP - 30624 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Balischewski, Christian A1 - Choi, Hyung-Seok A1 - Behrens, Karsten A1 - Beqiraj, Alkit A1 - Körzdörfer, Thomas A1 - Gessner, Andre A1 - Wedel, Armin A1 - Taubert, Andreas T1 - Metal sulfide nanoparticle synthesis with ionic liquids state of the art and future perspectives JF - ChemistryOpen N2 - Metal sulfides are among the most promising materials for a wide variety of technologically relevant applications ranging from energy to environment and beyond. Incidentally, ionic liquids (ILs) have been among the top research subjects for the same applications and also for inorganic materials synthesis. As a result, the exploitation of the peculiar properties of ILs for metal sulfide synthesis could provide attractive new avenues for the generation of new, highly specific metal sulfides for numerous applications. This article therefore describes current developments in metal sulfide nano-particle synthesis as exemplified by a number of highlight examples. Moreover, the article demonstrates how ILs have been used in metal sulfide synthesis and discusses the benefits of using ILs over more traditional approaches. Finally, the article demonstrates some technological challenges and how ILs could be used to further advance the production and specific property engineering of metal sulfide nanomaterials, again based on a number of selected examples. KW - Ionic liquids KW - ionic liquid crystals KW - ionic liquid precursors KW - metal KW - sulfides KW - catalysis KW - electrochemistry KW - energy materials KW - LED KW - solar KW - cells Y1 - 2021 U6 - https://doi.org/10.1002/open.202000357 SN - 2191-1363 VL - 10 IS - 2 SP - 272 EP - 295 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Figueroa Campos, Gustavo Adolfo A1 - Perez, Jeffrey Paulo H. A1 - Block, Inga A1 - Sagu Tchewonpi, Sorel A1 - Saravia Celis, Pedro A1 - Taubert, Andreas A1 - Rawel, Harshadrai Manilal T1 - Preparation of activated carbons from spent coffee and coffee parchment and assessment of their adsorbent efficiency JF - Processes : open access journal N2 - The valorization of coffee wastes through modification to activated carbon has been considered as a low-cost adsorbent with prospective to compete with commercial carbons. So far, very few studies have referred to the valorization of coffee parchment into activated carbon. Moreover, low-cost and efficient activation methods need to be more investigated. The aim of this work was to prepare activated carbon from spent coffee grounds and parchment, and to assess their adsorption performance. The co-calcination processing with calcium carbonate was used to prepare the activated carbons, and their adsorption capacity for organic acids, phenolic compounds and proteins was evaluated. Both spent coffee grounds and parchment showed yields after the calcination and washing treatments of around 9.0%. The adsorption of lactic acid was found to be optimal at pH 2. The maximum adsorption capacity of lactic acid with standard commercial granular activated carbon was 73.78 mg/g, while the values of 32.33 and 14.73 mg/g were registered for the parchment and spent coffee grounds activated carbons, respectively. The Langmuir isotherm showed that lactic acid was adsorbed as a monolayer and distributed homogeneously on the surface. Around 50% of total phenols and protein content from coffee wastewater were adsorbed after treatment with the prepared activated carbons, while 44, 43, and up to 84% of hydrophobic compounds were removed using parchment, spent coffee grounds and commercial activated carbon, respectively; the adsorption efficiencies of hydrophilic compounds ranged between 13 and 48%. Finally, these results illustrate the potential valorization of coffee by-products parchment and spent coffee grounds into activated carbon and their use as low-cost adsorbent for the removal of organic compounds from aqueous solutions. KW - coffee by-products KW - spent coffee grounds KW - parchment KW - valorization KW - calcination KW - activated carbon KW - organic compounds adsorption Y1 - 2021 U6 - https://doi.org/10.3390/pr9081396 SN - 2227-9717 VL - 9 IS - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - Heyne, Benjamin A1 - Arlt, Kristin A1 - Geßner, André A1 - Richter, Alexander F. A1 - Döblinger, Markus A1 - Feldmann, Jochen A1 - Taubert, Andreas A1 - Wedel, Armin T1 - Mixed Mercaptocarboxylic Acid Shells Provide Stable Dispersions of InPZnS/ZnSe/ZnS Multishell Quantum Dots in Aqueous Media JF - Nanomaterials N2 - Highly luminescent indium phosphide zinc sulfide (InPZnS) quantum dots (QDs), with zinc selenide/zinc sulfide (ZnSe/ZnS) shells, were synthesized. The QDs were modified via a post-synthetic ligand exchange reaction with 3-mercaptopropionic acid (MPA) and 11-mercaptoundecanoic acid (MUA) in different MPA:MUA ratios, making this study the first investigation into the effects of mixed ligand shells on InPZnS QDs. Moreover, this article also describes an optimized method for the correlation of the QD size vs. optical absorption of the QDs. Upon ligand exchange, the QDs can be dispersed in water. Longer ligands (MUA) provide more stable dispersions than short-chain ligands. Thicker ZnSe/ZnS shells provide a better photoluminescence quantum yield (PLQY) and higher emission stability upon ligand exchange. Both the ligand exchange and the optical properties are highly reproducible between different QD batches. Before dialysis, QDs with a ZnS shell thickness of ~4.9 monolayers (ML), stabilized with a mixed MPA:MUA (mixing ratio of 1:10), showed the highest PLQY, at ~45%. After dialysis, QDs with a ZnS shell thickness of ~4.9 ML, stabilized with a mixed MPA:MUA and a ratio of 1:10 and 1:100, showed the highest PLQYs, of ~41%. The dispersions were stable up to 44 days at ambient conditions and in the dark. After 44 days, QDs with a ZnS shell thickness of ~4.9 ML, stabilized with only MUA, showed the highest PLQY, of ~34%. KW - quantum dots KW - cadmium-free KW - Cd-free KW - InP KW - InPZnS KW - multishell KW - mercaptocarboxylic acids KW - 3-mercaptopropionic acid KW - 11-mercaptoundecanoic acid KW - phase transfer KW - ligand exchange KW - aqueous dispersion KW - QDs Y1 - 2020 U6 - https://doi.org/10.3390/nano10091858 SN - 2079-4991 VL - 10 IS - 9 PB - MDPI CY - Basel ER -