Article
Nanoscience & Nanotechnology
Matthias Schwartzkopf, Andre Rothkirch, Niko Carstens, Qing Chen, Thomas Strunskus, Franziska C. Loehrer, Senlin Xia, Christoph Rosemann, Lorenz Biessmann, Volker Koerstgens, Shiwani Ahuja, Pallavi Pandit, Jan Rubeck, Susann Frenzke, Alexander Hinz, Oleksandr Polonskyi, Peter Mueller-Buschbaum, Franz Faupel, Stephan Roth
Summary: In this study, we investigate in real time the formation of polymer-supported silver, copper, and silver-copper-alloy nanoclusters using in situ surface-sensitive X-ray scattering and optical spectroscopy. By tracking the growth morphology, surface plasmon resonance shifts, and growth kinetics, we are able to extract the influence of scaling effects on nucleation and phase selection. Our findings provide a crucial route to accurately tailor the plasmon resonances of nanosized clusters, which is essential for anti-counterfeiting applications.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Peter Walter, Markus Ilchen, JanTorben Roeh, Wiebke Ohm, Christian Bonar Zeuthen, Uwe Klemradt
Summary: This article presents an advanced sputtering technique for studying thin film growth with a focus on crystallization. It demonstrates the different stages of crystallization during the film growth process and how it can be used to optimize thin film quality, efficiency, and performance.
APPLIED SCIENCES-BASEL
(2021)
Article
Nanoscience & Nanotechnology
Mehmet Girayhan Say, Calvin J. Brett, Jesper Edberg, Stephan Roth, L. Daniel Soderberg, Isak Engquist, Magnus Berggren
Summary: Printed paper-based electronics offer a flexible, environmentally friendly, and low-cost solution for portable and wearable electronics. Researchers have demonstrated a scalable spray-coating approach to fabricate tailored paper electrodes for all-printed supercapacitors, which outperform drop-casting in electrode manufacturing. The printed paper-based supercapacitors exhibit low equivalent series resistance and high areal capacitance, making them suitable for powering electrochromic indicators.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Multidisciplinary
Zachary J. Comeau, Rosemary R. Cranston, Halynne R. Lamontagne, Adam J. Shuhendler, Benoit H. Lessard
Summary: This study demonstrates that the use of a static, strong magnetic field can improve the microstructure of phthalocyanine (Pc) thin-films, leading to a twofold increase in the mobility of organic thin-film transistors (OTFTs). The magnetic field increases the concentration of oxygen-induced radical species within the Pc thin-film, resulting in magnetic field induced changes to its microstructure and improved charge transport characteristics.
Article
Nanoscience & Nanotechnology
Shanshan Yin, Ting Tian, Christian L. Weindl, Kerstin S. Wienhold, Qing Ji, Yajun Cheng, Yanan Li, Christine M. Papadakis, Matthias Schwartzkopf, Stephan Roth, Peter Mueller-Buschbaum
Summary: In this study, a scalable printing technique was successfully developed to produce highly ordered mesoporous α-Fe2O3 thin films using a diblock copolymer as a structure-directing agent. The technique shows great potential for applications in energy conversion and storage.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Chemistry, Physical
Yuqin Zou, Johanna Eichhorn, Sebastian Rieger, Yiting Zheng, Shuai Yuan, Lukas Wolz, Lukas V. Spanier, Julian E. Heger, Shanshan Yin, Christopher R. Everett, Linjie Dai, Matthias Schwartzkopf, Cheng Mu, Stephan V. Roth, Ian D. Sharp, Chun-Chao Chen, Jochen Feldmann, Samuel D. Stranks, Peter Mueller-Buschbaum
Summary: By introducing ionic liquids into perovskite films, the crystal growth can be controlled, resulting in improved charge carrier dynamics and photovoltaic performance, leading to higher efficiency and fill factor.
Article
Chemistry, Physical
Neha Gupta, Dileep Kumar, Mukul Gupta, V. Srihari, R. J. Choudhary, S. K. Rai, Pooja Gupta
Summary: The study investigates the influence of Nb addition on the magneto-structural properties of magnetron sputtered Si/SiO2/W/(CoFeB)(1-x)Nb-x metal metalloid alloy thin films. The results show that increasing Nb content leads to a transition from amorphous to nanocrystalline structure, accompanied by the emergence of in-plane magnetic anisotropy and improved soft-magnetic behavior.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Andrei Chumakov, Calvin J. Brett, Korneliya Gordeyeva, Dirk Menzel, Lewis O. O. Akinsinde, Marc Gensch, Matthias Schwartzkopf, Wei Cao, Shanshan Yin, Manuel A. Reus, Michael A. Ruebhausen, Peter Mueller-Buschbaum, L. Daniel Soederberg, Stephan V. Roth
Summary: This study presents a facile technology for establishing mono-and multilayer surfaces using magnetic nanoparticles on solid and flexible substrates. The self-ordered magnetic thin nanofilms are obtained by exploiting the templating effect of cellulose nanofibrils and magnetic fields. The uniform magnetic coatings show preferred in-plane orientation of the hard-magnetic nanoparticles and exhibit high coercivity and perpendicular anisotropy.
ACS APPLIED NANO MATERIALS
(2022)
Review
Chemistry, Physical
Daniel da Silva Costa, Guinther Kellermann, Aldo F. Craievich, Lisandro J. Giovanetti, Cristian Huck-Iriart, Felix G. Requejo
Summary: The study investigated the thermally activated nanostructural transformations in a material consisting of a flat Si(001) wafer with a nanoporous Ni-doped silica film. Two simultaneous processes were observed through in situ grazing-incidence small-angle X-ray scattering during isothermal annealing, including the formation kinetics of oriented NiSi2 hexagonal nanoplates buried in the Si wafer and spherical Ni nanocrystals embedded in a Ni-doped silica thin film. Time invariance of average radii of Ni nanocrystals, together with time dependence of their number, and various parameters of the NiSi2 nanoplates buried in the Si wafer were established through the analysis of 2D scattering patterns.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Kai-En Hung, Yu-Sheng Lin, Yung-Jing Xue, Hau-Ren Yang, Yu-Ying Lai, Je-Wei Chang, Chun-Jen Su, An-Chung Su, Chain-Shu Hsu, U-Ser Jeng, Yen-Ju Cheng
Summary: A novel non-volatile additive, fluorinated bis(perfluorophenyl)pimelate (BF7), has been found to effectively improve the efficiency and thermal stability of highly efficient organic solar cells (OSCs). The addition of BF7 to the active layer of the OSCs results in improved fractal-like network structures and elevated thermal stability, leading to higher power conversion efficiency (PCE). Similar effects are observed in another OSC system.
ADVANCED ENERGY MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Anna Lena Oechsle, Julian E. Heger, Nian Li, Shanshan Yin, Sigrid Bernstorff, Peter Mueller-Buschbaum
Summary: This study investigates the stability of organic thermoelectric thin films at elevated operating temperatures. The electrical conductivity of ethyl-3-methylimidazolium dicyanamide (EMIM DCA) post-treated poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) thin films is measured over 4.5 h of heating at 50 or 100 °C for different EMIM DCA concentrations. The changes in electrical performance are correlated with changes in film morphology and PEDOT oxidation level, resulting in a degradation of thermoelectric properties.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Review
Chemistry, Multidisciplinary
Minchao Qin, Pok Fung Chan, Xinhui Lu
Summary: Understanding the film formation mechanisms of metal halide perovskites is crucial for achieving high-quality perovskite films and high-performance devices. However, due to the complexity of perovskite composition, dimensionality, and processing conditions, this remains a great challenge.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Physical
Claudia Daniela Bojorge, Eduardo Armando Heredia, Horacio Ricardo Canepa
Summary: The main objective of this article is to determine the suitable range of incidence angles for analyzing GISAXS images in order to describe the porosity of the studied sample. A nanostructured ZnO film synthesized by sol-gel method was characterized using XRD, FESEM, and GISAXS. It is found that the reliable results are obtained when the incidence angles are between the critical angle and the lowest angle that allows the incident radiation to penetrate the total thickness.
SURFACES AND INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Shanshan Yin, Wei Cao, Qing Ji, Yajun Cheng, Lin Song, Nian Li, Christian L. Weindl, Matthias Schwartzkopf, Stephan Roth, Peter Muller-Buschbaum
Summary: In this study, morphology-controlled α-Fe2O3 thin films were successfully synthesized using PS-b-P4VP diblock copolymer assisted sol-gel chemistry. Different solvent categories and polymer-to-FeCl3 ratios were systematically varied to tune the morphology of the thin films. The results show that solvent selectivity and polymer concentration play important roles in determining the morphology of the thin films.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Shanshan Yin, Wei Cao, Qing Ji, Yajun Cheng, Lin Song, Nian Li, Christian L. Weindl, Matthias Schwartzkopf, Stephan Roth, Peter Muller-Buschbaum
Summary: Mesoporous alpha-Fe2O3 thin films with large area homogeneity show great potential in various applications. In this work, morphology-controlled thin films were synthesized using PS-b-P4VP diblock copolymer assisted sol-gel chemistry. By adjusting the solvent type and polymer-to-FeCl3 ratio, the morphology of the thin films can be systematically tuned, leading to different nanocluster structures and porous formations. Adjusting the solvent selectivity in DMF/1,4-dioxane solvent mixtures also results in a transition from spherical to wormlike pore shapes.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Anna Aubele, Yakun He, Teresa Kraus, Ning Li, Elena Mena-Osteritz, Paul Weitz, Thomas Heumueller, Kaicheng Zhang, Christoph J. Brabec, Peter Baeuerle
Summary: A novel donor-acceptor dyad, 4, with excellent photovoltaic performance and stability, has been synthesized and applied in solution-processed single-material organic solar cells (SMOSCs).
ADVANCED MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Yakun He, Benedict Hanisch, Andres Osvet, Larry Luer, Anna Aubele, Peter Bauerle, Weiwei Li, Ning Li, Christoph J. Brabec
Summary: The exciton dissociation between donor and acceptor is crucial for determining the photovoltaic performance of organic solar cells. Time-resolved photoluminescence investigations offer a potential method to separately determine the exciton splitting efficiency of donor and acceptor moieties in single component materials. Post-treatment can adjust the exciton splitting efficiency of donor or acceptor moieties separately in these materials, while excessive phase separation occurs in BHJ composites under external stress.
ISRAEL JOURNAL OF CHEMISTRY
(2022)
Article
Microscopy
Birk Fritsch, Mingjian Wu, Andreas Hutzler, Dan Zhou, Ronald Spruit, Lilian Vogl, Johannes Will, H. Hugo Perez Garza, Martin Marz, Michael P. M. Jank, Erdmann Spiecker
Summary: This study presents a method for in situ temperature measurement utilizing parallel-beam electron diffraction at gold nanoparticles, achieving sub-Kelvin precision in both vacuum and gaseous environments. The technique is applied to characterize the local thermal stability of a state-of-the-art gas cell with heating capability. The findings provide crucial reference for in situ investigations into catalysis.
Article
Energy & Fuels
Shanshan Qin, Nikita Denisov, Johannes Will, Jan Kolarik, Erdmann Spiecker, Patrik Schmuki
Summary: Removing non-active Pt SAs on TiO2 by cyanide leaching dramatically increases the co-catalytic activity of remaining Pt SAs, achieving a remarkable turnover frequency of 4.87 x 10(5) h(-1) for H-2 evolution.
Article
Electrochemistry
Gihoon Cha, Anca Mazare, Imgon Hwang, Nikita Denisov, Johannes Will, Tadahiro Yokosawa, Zdenek Badura, Giorgio Zoppellaro, Alexander B. Tesler, Erdmann Spiecker, Patrik Schmuki
Summary: Single-crystal TiO2 nanoflakes decorated with Pt single atoms show higher photocatalytic H-2 production at lower Pt loading compared to traditional Pt nanoparticles.
ELECTROCHIMICA ACTA
(2022)
Article
Energy & Fuels
Christina Harreiss, Stefan Langner, Mingjian Wu, Marvin Berlinghof, Stefanie Rechberger, Johannes Will, Michele Conroy, Ursel Bangert, Tobias Unruh, Christoph J. Brabec, Erdmann Spiecker
Summary: This study investigates the influence of solvent vapor annealing on nanomorphology, crystallinity, and performance by utilizing advanced transmission electron microscopy methods. The results show that the choice of solvent significantly affects the establishment rate of device efficiency, while the donor solubility controls the diffusion and crystallization kinetics of the blend molecules. Additionally, the domain size and single-crystalline nature of DRCN5T fibers are found to be crucial for achieving the highest efficiency.
Article
Chemistry, Multidisciplinary
Imgon Hwang, Anca Mazare, Johannes Will, Tadahiro Yokosawa, Erdmann Spiecker, Patrik Schmuki
Summary: This study demonstrates the decoration of anodic TiO2 nanotubes with single atoms of noble metals Pt, Pd, Rh, and Au using a simple dark deposition approach. Among these noble-metal single atoms, Pd exhibits the highest hydrogen production rate and can effectively inhibit the recombination of hydrogen and oxygen, leading to enhanced photocatalytic performance for water splitting.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Hany A. Afify, Viktor Rehm, Anastasiia Barabash, Albert These, Jiyun Zhang, Andres Osvet, Christoph Schuesslbauer, Dominik Thiel, Tobias Ullrich, Martin Dierner, Thomas Przybilla, Johannes Will, Erdmann Spiecker, Dirk M. Guldi, Christoph J. Brabec, Wolfgang Heiss
Summary: This study demonstrates an antisolvent-vapor-assisted crystallization method for epitaxial growth of metal-halide-perovskites. By controlling the shape of micro-crystallites, single-mode operation of lasers with high environmental stability can be achieved, which is competitive with vapor-phase epitaxial microstructures.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Nikita Denisov, Shanshan Qin, Johannes Will, Bojana Nedic Vasiljevic, Natalia V. Skorodumova, Igor A. Pasti, Bidyut Bikash Sarma, Benedict Osuagwu, Tadahiro Yokosawa, Johannes Voss, Janis Wirth, Erdmann Spiecker, Patrik Schmuki
Summary: This paper describes the photoinduced destabilization of Pt single atoms (SAs) on the surface of titanium dioxide (TiO2), a benchmark photocatalyst. The SAs agglomerate into clusters and nanoparticles under illumination in aqueous solutions. The kinetics of this process depend on the presence of sacrificial hole scavengers and the intensity of light used. Despite the aggregation and reduction of the SAs, the overall photocatalytic hydrogen evolution remains largely unaffected.
ADVANCED MATERIALS
(2023)
Article
Crystallography
Christian Kupfer, Jack Elia, Masashi Kato, Andres Osvet, Christoph J. Brabec
Summary: This paper presents a novel and facile synthesis route to obtain phase-pure Cs2TiBr6 and its lesser-studied iodine-based relatives via high-energy mechanochemical ball milling. The materials have certain optoelectronic properties and show potential for photovoltaic applications.
CRYSTAL RESEARCH AND TECHNOLOGY
(2023)
Article
Chemistry, Physical
Si-Ming Wu, Imgon Hwang, Benedict Osuagwu, Johannes Will, Zhenni Wu, Bidyut Bikash Sarma, Fu-Fei Pu, Li-Ying Wang, Zdenek Badura, Giorgio Zoppellaro, Erdmann Spiecker, Patrik Schmuki
Summary: Anchoring single platinum atoms on titanium dioxide nanosheets with lattice incorporated fluorine species can achieve uniform dispersion and high efficiency in photocatalytic hydrogen production. The fluorine-stabilized platinum atoms exhibit remarkable photocatalytic activity, with a high production rate and excellent stability in long-term reactions.
Article
Chemistry, Physical
Shanshan Qin, Johannes Will, Hyesung Kim, Nikita Denisov, Simon Carl, Erdmann Spiecker, Patrik Schmuki
Summary: We disperse Pt single atoms on TiO2 thin films and evaluate the photocatalytic H-2 generation. We find that a minuscule loading of Pt single atoms is sufficient to achieve maximized H-2 production rate under common illumination intensities. The overall reaction rate is determined by charge carrier generation, rather than the density of co-catalytic sites.
ACS ENERGY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Sebastian W. Krauss, Mirco Eckardt, Johannes Will, Erdmann Spiecker, Renee Siegel, Martin Dulle, Ralf Schweins, Brian Pauw, Juergen Senker, Mirijam Zobel
Summary: The isotopic effect of exchanging H2O with D2O can impact the formation mechanism and colloidal stability of nanoparticles. The equilibrium and dynamics of ligand clusters in solution are changed by the exchange, affecting the size and crystallinity of the nanoparticles. In D2O, the colloidal stability of CdS nanoparticles covered by complexes is significantly reduced.
Article
Chemistry, Multidisciplinary
Sebastian W. Krauss, Mirco Eckardt, Johannes Will, Erdmann Spiecker, Renee Siegel, Martin Dulle, Ralf Schweins, Brian Pauw, Juergen Senker, Mirijam Zobel
Summary: This study investigates the impact of heavy water (D2O) on CdS nanoparticle formation and colloidal stability. The results suggest that the isotopic effect of D2O influences nanoparticle formation by altering the equilibria and dynamics of ethylenediaminetetraacetate (EDTA) clusters in solution. Despite the stabilizing effect of EDTA in normal water, the colloidal stability of CdS nanoparticles is significantly reduced in heavy water.
