Article
Chemistry, Physical
Liangliang Yang, Jiangtao Wei, Yuanhao Qin, Lei Wei, Peishuai Song, Mingliang Zhang, Fuhua Yang, Xiaodong Wang
Summary: Thermoelectric technology offers advantages such as quiet operation, zero emissions, and long life, but its large-scale application is limited by the lower thermoelectric performance factor (ZT). By growing Cu2Se thin films using magnetron sputtering, researchers achieved high conductivity and ZT values. This work lays the foundation for further research on nano-thin-film thermoelectrics.
Article
Chemistry, Multidisciplinary
Zhenxue Zhang, Mikdat Gurtaran, Xiaoying Li, Hio-Ieng Un, Yi Qin, Hanshan Dong
Summary: In this study, N-type and P-type BiTe-based thin films were deposited on silicon, glass, and Kapton HN polyimide foil using magnetron sputtering technique. The morphology, microstructure, and phase constituents of the thin films were characterized by SEM/EDX, XRD, and TEM. The electrical conductivity, thermal conductivity, and Seebeck coefficient were measured by an advanced in-plane test system. The power output (open-circuit voltage and electric current) of the thin films was measured at different temperature gradients using a custom-built apparatus. The impact of deposition parameters and the dimensions of the thin films on the power output were investigated to optimize the thin-film flexible TE device for thermal energy harvesting.
Article
Materials Science, Multidisciplinary
Guangqiang He, Zhihui Xiong, Hui Yang, Ming Yang, Zhixi Li, Tixian Zeng, Xinyou An, Min Zhang
Summary: Cadmium chalcogenide thin films (CdSe0.2Te0.8) were successfully deposited on glass substrates by radio frequency magnetron sputtering, exhibiting a cubic zinc-blende structure with no secondary phases. The band gap of CdSe0.2Te0.8 varied slightly with film thickness in the range of 1.41-1.43 eV, making them potentially suitable for use as a photovoltaic absorption layer in ultra-thin solar cells.
Article
Materials Science, Multidisciplinary
Shinho Cho
Summary: The study investigated the effects of substrate temperature on YVO4:Eu3+ phosphor thin films. It was found that all thin films exhibited a strong crystalline orientation and emission spectra in specific bands regardless of substrate temperature. Increasing substrate temperature led to enhanced red emission intensity, indicating a significant impact on the film's performance.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2021)
Article
Chemistry, Physical
C. M. Furqan, Jacob Y. L. Ho, H. S. Kwok
Summary: This article reports the growth of GaN thin film on low-cost electronic substrate using magnetron sputtering method. Various characterization techniques were used to explore the optical and structural properties, revealing the effects of different growth parameters on the film properties. XRD studies, raman spectroscopy, as well as mu-PL and optical transmittance experiments provided insights into the thin film properties under different growth conditions.
SURFACES AND INTERFACES
(2021)
Article
Chemistry, Physical
Lei Ye, Jia Zheng, Cong Guo, Yu Hu, Jian Yu, Xiaodong Zhu, Tao Chen
Summary: This study demonstrates that high deposition pressure can significantly impact the material properties of sputtered SiC thin films, altering the chemical bonding, composition, and opto-electrical properties. It shows that an increase in deposition pressure leads to a higher oxygen content and a change in the carbon phase, potentially meeting the application requirements for optoelectronic devices.
APPLIED SURFACE SCIENCE
(2023)
Article
Materials Science, Coatings & Films
P. Moskovkin, C. Maszl, R. Schierholz, W. Breilmann, J. Petersen, A. Pflug, J. Muller, M. Raza, S. Konstantinidis, A. von Keudell, S. Lucas
Summary: The study focuses on correlating basic plasma properties with morphological, structural and mechanical properties of thin films deposited by high power impulse magnetron sputtering. By studying the deposition and growth of titanium films at various discharge power densities, a transition from thermally-driven to ballistically-driven Ti atom mobility was revealed. Changes in micro-crystal orientation and nano hardness of the films were observed as discharge power density increased, alongside non-monotonic variations in surface roughness behavior.
SURFACE & COATINGS TECHNOLOGY
(2021)
Article
Chemistry, Physical
Faiza Salhi, Linda Aissani, Mamoun Fellah, Abdelhakim Chadli, Abderrahmane Cheriet, Ahlam Belgroune, Corinne Nouveau, Aleksei Obrosov, Mohammed Abdul Samad, Akram Alhussein
Summary: The study investigated the effects of varying Zr content on the structure, surface properties, and mechanical performance of TiZrN thin films. It was found that increasing Zr content led to changes in lattice parameter, film thickness, and surface energy. The TiZrN film containing 18.3 at.% Zr demonstrated the best tribo-mechanical performance with low friction coefficient and wear rate.
SURFACES AND INTERFACES
(2021)
Review
Engineering, Chemical
Ying Yang, Yanxiang Zhang, Mufu Yan
Summary: Solid oxide fuel cells (SOFCs) are attractive energy conversion devices due to their fuel flexibility, environmental friendliness, and promising energy conversion efficiency. However, the high operating temperature of SOFCs poses challenges in stability, sealing integrity, and safety. Lowering the operating temperature to 600°C or lower is an important research topic. Magnetron sputtering is gaining attention as a thin-film preparation technology for electrolyte thin films with high stability and performance at lower temperatures. This comprehensive review analyzes various electrolyte preparation methods, focusing on magnetron sputtering technology for oxygen-ion conducting electrolyte thin films. The effects of processing parameters on the microstructures and properties of the thin films, as well as the relevant interfaces and full SOFCs, are discussed. Perspectives and directions for developing high-performance SOFCs with thin-film electrolytes prepared by magnetron sputtering technology are presented.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Chemistry, Physical
M. Cervena, R. Cerstvy, T. Dvorak, J. Rezek, P. Zeman
Summary: Binary W-Zr thin-film alloys with different metastable structures were prepared using DC magnetron sputtering. The microstructure and properties of the films were found to be related to the individual metastable structures prepared. The hardness of the films varied with the elemental composition, with W-rich films showing enhanced hardness and reduced residual stress, while amorphous W-Zr films exhibited low surface roughness and metallic glass features.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Metallurgy & Metallurgical Engineering
Siavash Bakhtiarnia, Saeed Sheibani, Alain Billard, Eric Aurry, Mohammad Arab Pour Yazdi
Summary: Nanoporous BiVO4 thin films were successfully deposited using reactive magnetron sputtering, exhibiting good crystal structure, morphology, and photocatalytic properties. The films showed the highest porosity and lowest bandgap under specific conditions, demonstrating excellent photocatalytic activity.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2022)
Article
Chemistry, Multidisciplinary
Zhengtao Wu, Yintuan Zhang, Qimin Wang, Kwang-Ho Kim, Se-Hun Kwon
Summary: The microstructure and properties of WTi alloy films with different contents of Ti prepared by magnetron sputtering were investigated. The electrical resistivity increased with the increase in Ti content. The alloy film with 6.8 at.% Ti showed the highest temperature coefficient of resistance, which decreased gradually after thermal resistance tests and annealing treatment. The WTi films exhibited excellent stability in thermal resistance tests and have potential applications in temperature measurement of tools and dies.
APPLIED SCIENCES-BASEL
(2023)
Article
Engineering, Chemical
Anton S. Tarasov, Sergey A. Lyaschenko, Mikhail V. Rautskii, Anna V. Lukyanenko, Tatiana A. Andryushchenko, Leonid A. Solovyov, Ivan A. Yakovlev, Olga A. Maximova, Dmitriy V. Shevtsov, Mikhail A. Bondarev, Ilya A. Bondarev, Sergei G. Ovchinnikov, Sergey N. Varnakov
Summary: The growth and phase formation features of Cr2GeC and Cr(2-x)MnxGeC MAX phase thin films synthesized by magnetron sputtering technique were studied, along with the influence of structure and morphology on their electronic, optical, and transport properties. It was found that the Cr:Ge:C atomic ratios played a key role in the formation of the MAX phase thin film, and carbon and manganese doping could improve the phase composition of the films. The crystalline structure and morphology of the thin films affected their optical and transport properties.
Article
Materials Science, Multidisciplinary
R. Graillot-Vuillecot, A-L Thomann, T. Lecas, C. Cachoncinlle, E. Millon, A. Caillard
Summary: Titanium dioxide thin films were synthesized using magnetron sputtering in two configurations: cold target and hot target. The study found differences in crystalline quality and morphology of the films between the two configurations. Optical transmission measurements showed that the optical band gaps of the films could be tuned based on the deposition configuration.
Article
Physics, Multidisciplinary
Rahul Godiwal, Amit Kumar Gangwar, Jyoti Jaiswal, Pargam Vashishtha, Modassar Hossain, Prabir Pal, Govind Gupta, Preetam Singh
Summary: This study compares the effects of balanced and unbalanced magnetron configurations on room temperature sputtered ZnO thin films, finding that the unbalanced magnetron configuration significantly improves the crystalline quality, band gap, and surface properties of the films.
Article
Chemistry, Physical
Raphael Poulain, Jochen Rohrer, Yannick Hermans, Christian Dietz, Joachim Brotz, Joris Proost, Marian Chatenet, Andreas Klein
Summary: The interaction between water and oriented NiO films was studied using a combination of photoelectron spectroscopy, in situ sample preparation, and electrochemical measurements. The exposure to room temperature water induced a more positive surface charge on the (110)- and (111)-oriented films compared to NiO(100), which was attributed to dissociative adsorption of water and removal of oxygen. This explains the role of water as an electron donor on oxide surfaces.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Hans F. Wardenga, Katharina N. S. Schuldt, Stephan Waldow, Roger A. De Souza, Andreas Klein
Summary: The study investigated the influence of different doping methods, concentrations, and surface orientations on the surface Fermi level positions, ionisation potentials, and work functions of CeO2. It was found that the ionisation potentials are significantly affected by doping and oxygen activity, while the work functions are largely unaffected. In terms of oxygen surface exchange coefficients, similar magnitudes were observed under different conditions.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Elaheh Ghorbani, Lorenzo Villa, Paul Erhart, Andreas Klein, Karsten Albe
Summary: This study presents a systematic assessment of the behavior of self-trapped electrons in PbTiO3, a prototypical ferroelectric material with various technological applications. The study aimed to identify the parameters used in density functional theory (DFT) that accurately predict the properties of self-trapped electrons. It was found that the choice of pseudopotential and lattice parameters significantly influenced the magnitude of the trapping energy. A comparison of two different functionals showed the DFT-PU result to be close to the HSE06 result. The study also provided configuration coordinate diagrams for the polaron-associated absorption and luminescence peaks in PbTiO3.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Nicole Bein, Brigita Kmet, Tadej Rojac, Andreja Bencan Golob, Barbara Malic, Julian Moxter, Thorsten Schneider, Lovro Fulanovic, Maryam Azadeh, Till Froemling, Sonja Egert, Hongguang Wang, Peter van Aken, Jutta Schwarzkopf, Andreas Klein
Summary: The valence band maximum energy of NaNbO3 is determined and found comparable to SrTiO3 and BaTiO3, while the conduction band minimum is yet to be determined. In addition, Sr- and Ca-doped NaNbO3 ceramics exhibit low electrical conductivity.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Julia E. Medvedeva, Bishal Bhattarai, Ivan A. Zhuravlev, Federico Motti, Piero Torelli, Anita Guarino, Andreas Klein, Emiliano Di Gennaro, Fabio Miletto Granozio
Summary: Understanding the short-range structure of amorphous materials is crucial for predicting their macroscopic properties. This study investigates the contradictory experimental findings regarding the oxygen environment of titanium in amorphous strontium titanate and reveals that the discrepancy is caused by differences in the material's density. The study also analyzes the density-dependent structural characteristics and electronic properties of amorphous strontium titanate, providing insights into the structure-property relationship.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Materials Science, Ceramics
A. Aubert, J. S. Garitaonandia, F. Maccari, J. Broetz, K. Skokov, O. Gutfleisch
Summary: Recent research has shown that uniaxial magnetic anisotropy can be induced in Cobalt ferrite (CFO) by reactive sintering using spark plasma sintering (SPS), improving its magnetostrictive properties. This study investigates the parameters responsible for the induced anisotropy and identifies that it arises during cooling under SPS's uniaxial compression. Additionally, the study explores the fundamental origin of the magnetic anisotropy and find that it is caused by the ionic distribution of Co2+ in the CFO's spinel lattice. These findings advance the understanding of the relationship between SPS processing and magnetic properties of cobalt ferrite.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Physical
Issei Suzuki, Binxiang Huang, Sakiko Kawanishi, Takahisa Omata, Andreas Klein
Summary: This study demonstrates that the Fermi energy of SnS at the interface can be shifted through the entire band gap, indicating the absence of Fermi-level pinning. The mechanisms behind the existence or lack of Fermi-level pinning at SnS interfaces were discussed, and suggestions were offered to achieve higher photovoltages by avoiding Fermi-level pinning in SnS solar cells.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Physics, Applied
Yunwei Sheng, Mathieu Mirjolet, Mario Villa, Jaume Gazquez, Jose Santiso, Andreas Klein, Jordi Fraxedas, Josep Fontcuberta
Summary: Epitaxial LaFeO3-based photocells with different thicknesses were grown on LSAT single-crystal substrates, using LSMO and Pt/BLSO electrodes, to determine their photoresponse. The short-circuit photocurrent initially increases and then decreases with LFO thickness, and is larger or smaller with Pt or BLSO electrodes. The open-circuit voltage shows the opposite trend, being smaller or larger with Pt and BLSO, respectively, consistent with the electronic band alignments and rectifying character of the dark current-voltage data. The complex microstructure and grain boundaries of the films play a significant role in the observed responsivity, which is larger than in similar LFO-based structures.
PHYSICAL REVIEW APPLIED
(2023)
Article
Chemistry, Physical
Shanmugapriya Periyannan, Laura Manceriu, Andreas Klein, Wolfram Jaegermann, Catherine Henrist, Rudi Cloots
Summary: In this study, a surface cleaning procedure involving vacuum annealing under oxygen was employed to clean the ZNR scaffold film's surface before NiO deposition for heterostructure formation. The properties of the scaffold were studied and correlated to the NiO/ZNR interface and photo-response properties. The optimized NiO/ZNR showed improved photo-response and photodegradation efficiency compared to the ZNR scaffold.
Article
Engineering, Aerospace
Johannes Broetz, Christian Schaenzle, Peter F. Pelz
Summary: The efficiency definition allows comparison between two machines, typically expressed as the ratio of usable power to required power. While engineers primarily analyze efficiency using the first law of thermodynamics, this paper introduces the concept of exegetic efficiency by considering the second law. Exergy analysis accurately models reality by considering work and heat. By comparing isentropic and exergetic efficiencies, using a high-pressure radial fan as an example, the paper highlights their differences. The investigation emphasizes the importance of heat flux in non-adiabatic fans and concludes that the exergetic efficiency is significant in high-pressure, partial-load ranges.
INTERNATIONAL JOURNAL OF TURBOMACHINERY PROPULSION AND POWER
(2023)
Article
Chemistry, Multidisciplinary
Binxiang Huang, Paul Erhart, Tongqing Yang, Andreas Klein
Summary: Interface stability is crucial for the reliable performance of electronic and electrochemical devices. In this study, an operando analysis approach using photoelectron spectroscopy in a solid oxide electrochemical cell was introduced to investigate interfaces. The experiment provided chemical and electronic information, revealing the importance of both chemical and electrostatic boundary conditions for interface stability. The approach was demonstrated using (anti-)ferroelectric (Pb,La)(Zr,Sn,Ti)O-3 dielectrics.
ADVANCED MATERIALS INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Issei Suzuki, Zexin Lin, Taichi Nogami, Sakiko Kawanishi, Binxiang Huang, Andreas Klein, Takahisa Omata
Summary: Recently, it has been reported that there is a large band bending at the interface between n-type single crystalline SnS and MoO3, which has a high work function. In this study, we applied this interface to solar cells for the first time and evaluated its photovoltaic properties. The highest achieved open-circuit voltage (V-OC) was 437 mV, which is lower than the expected value but the highest recorded for SnS solar cells. The highest power conversion efficiency (PCE) was 4.4%. Based on device parameter analysis, we propose methods for improving the device performance, including V-OC, short-circuit current, and PCE. The study also estimated the carrier-collection length of n-type SnS single crystals to be around 200 nm using external quantum efficiency measurements. This study demonstrates that the V-OC of SnS solar cells can be improved by fabricating a junction with MoO3 thin films.
Article
Nanoscience & Nanotechnology
Nils Ulrich, Michelle Schaefer, Melina Roemer, Sascha Dominic Straub, Siyuan Zhang, Joachim Broetz, Christina Trautmann, Christina Scheu, Bastian J. M. Etzold, Maria Eugenia Toimil-Molares
Summary: Three-dimensional and highly interconnected copper nanowire networks were prepared by electro-deposition in etched ion track polymer templates and used as catalysts for electrochemical CO2 reduction in an aqueous electrolyte to produce hydrocarbons and alcohols. The specific surface area of the nanowire networks could be adjusted by controlling the wire length, diameter, and number density, ranging from 70 cm2 to 300 cm2 per cm2 sample area. The conversion efficiency and selectivity of CO2 reduction were studied as a function of the applied potential, and the stability of the nanowire networks during CO2 reduction was confirmed.
ACS APPLIED NANO MATERIALS
(2023)
Article
Materials Science, Ceramics
Andreas Klein, Karsten Albe, Nicole Bein, Oliver Clemens, Kim Alexander Creutz, Paul Erhart, Markus Frericks, Elaheh Ghorbani, Jan Philipp Hofmann, Binxiang Huang, Bernhard Kaiser, Ute Kolb, Jurij Koruza, Christian Kuebel, Katharina N. S. Lohaus, Juergen Roedel, Jochen Rohrer, Wolfgang Rheinheimer, Roger A. Souza, Verena Streibel, Anke Weidenkaff, Marc Widenmeyer, Bai-Xiang Xu, Hongbin Zhang
Summary: Chemical substitution is a primary strategy for tailoring material properties, with isovalent and heterovalent substitution being the two types. By controlling the different compensation mechanisms, it is possible to predict and adjust material properties. The Fermi energy can be used as a common descriptor for these mechanisms.
JOURNAL OF ELECTROCERAMICS
(2023)
Article
Engineering, Electrical & Electronic
Raphael Poulain, Gunnar Lumbeeck, Jonas Hunka, Joris Proost, Henri Savolainen, Hosni Idrissi, Dominique Schryvers, Nicolas Gauquelin, Andreas Klein
Summary: Although there are contradictory results on the properties of nickel oxide (NiO) in the literature, this comprehensive study provides valuable insights into the conductivity, surface properties, and charge defects compensation mechanism of NiO materials. The experiments reveal that the surface and bulk properties of NiO are strongly influenced by the deposition temperature, leading to variations in the Fermi level pinning, work function, and grain boundaries. This study contributes to a better understanding of the electrical conductivity and charge compensation mechanism of NiO thin films.
ACS APPLIED ELECTRONIC MATERIALS
(2022)
