Article
Nanoscience & Nanotechnology
Yu Ding, Qi Xue, Qing-Ling Hong, Fu-Min Li, Yu-Cheng Jiang, Shu-Ni Li, Yu Chen
Summary: In this study, ultrathin cobalt sulfide nanosheets (Co3S4-NSs) on nickel foam (NiF) nanohybrids were synthesized and demonstrated excellent catalytic activity and selectivity for ethanol oxidation reaction and hydrogen evolution reaction. A symmetric Co3S4-NSs/Ni-F electrolyzer was successfully constructed, requiring only 1.48 V electrolysis voltage for high-purity hydrogen generation and value-added potassium acetate production.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Kveta Jiratova, Roman Perekrestov, Michaela Dvorakova, Jana Balabanova, Martin Kostejn, Martin Vesely, Martin Cada, Pavel Topka, Dana Pokorna, Zdenek Hubicka, Frantisek Kovanda
Summary: Magnetron sputtering is an advantageous method for preparing catalysts supported on stainless steel meshes, particularly for processes carried out at high space velocities. The CoOx-MnOx and CoOx-CoMnOx catalysts showed high catalytic activity on stainless steel meshes, with the thinnest layer displaying the highest catalytic activity. Compared to the commercial pelletized Co-Mn-Al mixed oxide catalyst, the sputtered catalysts demonstrated significantly higher catalytic activity despite lower content of the Co and Mn active components.
Article
Chemistry, Physical
Nadeem Asghar Khan, Iqbal Ahmad, Naghmana Rashid, Muhammad Nadeem Zafar, Farooq Khurum Shehzad, Zahid Ullah, Anwar Ul-Hamid, Muhammad Faizan Nazar, Muhammad Junaid, Muhammad Faheem, Syed Salman Shafqat, Uzma Jabeen, Alaa Dahshan
Summary: This study synthesized Co3O4, Co9S8, and their heterostructure Co3O4/Co9S8 as water oxidation catalysts, and found that the Co3O4/Co9S8 heterostructure showed excellent electrocatalytic activity at low onset potential, along with good long-term stability and a low Tafel slope.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Muhammad Zahir Iqbal, Junaid Khan, Shahid Alam, Rashid Ali, Muhammad Javaid Iqbal, Amir Muhammad Afzal, Sikandar Aftab
Summary: This study demonstrates the tuned electrochemical performance of cobalt phosphate via introducing a magnetron sputtered copper interfacial layer, providing a new approach for potential supercapattery devices. The electrode material showed superior specific capacity and electrochemical performance with excellent cyclic stability. The designed supercapattery exhibited efficient charge storage and release at different charge-discharge rates.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Chemistry, Physical
Viktor Johanek, Petr Svenda, Karel Masek
Summary: Methanol oxidation catalyzed by bi-layered or mixed oxides of cobalt and cerium was studied using temperature-programmed reaction technique at atmospheric pressure. The results showed that the CeO2/CoOx configuration was more active and stable than CoOx alone, demonstrating a synergistic interaction between cerium and cobalt in the mixed oxide catalyst. Further optimization of reactivity can be achieved through control of adlayer coverage.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Analytical
Xingli Wang, Junyu Ge, Nicole Ru-Xuan Ang, Kun Liang, Chong-Wei Tan, Hong Li, Beng Kang Tay
Summary: In this study, Sb nanofilms with lateral dimensions on the centimeter scale and controllable film thickness were successfully prepared using low-power magnetron sputtering deposition. The control of the deposition temperature was found to be important for the final crystalline structure of the nanofilms. Furthermore, the application of the nanofilms as a catalyst for water splitting was demonstrated.
Article
Nanoscience & Nanotechnology
Jing Miao, Xiaojun Zhao, Hang-Yang Hu, Hao Huang, Yu Ding, Zhi-Hong Liu, Yu Chen
Summary: In this study, trimetallic RhNiFe phosphide nanosheets on nickel foam (RhNiFe-P/NF) with high electrocatalytic activity were synthesized as a bifunctional electrocatalyst for hydrogen evolution reaction (HER) and ethanol oxidation reaction (EOR). The RhNiFe-P/NF material demonstrated a lower cell voltage and higher efficiency in the oxidation reaction, along with the generation of valuable byproduct.
ACS APPLIED NANO MATERIALS
(2022)
Article
Chemistry, Physical
Bing Lan, Qiong-Lan Wang, Zhao-Xia Ma, Ya-Juan Wu, Xiao-Le Jiang, Wei-Shang Jia, Cai-Xia Zhou, Yao-Yue Yang
Summary: The research team successfully improved the CO2 selectivity of ethanol oxidation reaction by fabricating highly-dispersive Bi(OH)(3) species on Rh interfaces, addressing the poisoning effect of C1 intermediates on the original Rh activity. The strong interaction between Rh and Bi(OH)(3) enhanced the catalyst's activity and stability.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Engineering, Environmental
Le Chai, Shuling Liu, Shaotong Pei, Chao Wang
Summary: This paper presents a series of cobalt-nickel phosphide films electrodeposited on nickel foam substrates, exhibiting good catalytic activity in alkaline solutions for both the hydrogen evolution reaction and water oxidation reaction. The electrodes show low overpotentials and steep Tafel slopes, with potential applications in electrolyzing water for hydrogen production.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Physical
Hui Fu, Nan Zhang, Feili Lai, Longsheng Zhang, Suli Chen, Hanjun Li, Kezhu Jiang, Ting Zhu, Fangping Xu, Tianxi Liu
Summary: This study designs a three-dimensional PtCu nanoframe material with efficient bifunctional catalysis for HER and EOR. The material shows low onset voltage and high oxidation efficiency in the coupled HER/EOR, while converting ethanol to acetate. This finding is of great significance for bifunctional electrocatalysts and energy-saving hydrogen production.
Article
Materials Science, Coatings & Films
J. T. Gudmundsson, J. Fischer, B. P. Hinriksson, M. Rudolph, D. Lundin
Summary: The ionization region model (IRM) is used to model high power impulse magnetron sputtering (HiPIMS) discharges with a Cu target. By applying the model to three previously explored discharges and thin copper film deposition, the internal plasma process parameters are quantified to understand the differences between these discharges. It is found that Cu+ ions dominate the ion current to the target surface and that self-sputter recycling is the main mechanism for reaching high discharge currents.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Wei Wu, Yongliang Tang, Bo Li, Xia Xiang, Chunming Liu, Xiaotao Zu
Summary: PbSe nanocrystalline films were prepared using magnetron sputtering with different parameters, showing improved crystallization quality and Pb/Se atomic ratio with increasing sputtering power and deposition time. The morphology of PbSe particles changed with deposition time, affecting the optical band gap and luminescence performance. Adjusting sputtering power and deposition time can optimize the properties of PbSe films.
Article
Physics, Applied
M. Rudolph, N. Brenning, H. Hajihoseini, M. A. Raadu, T. M. Minea, A. Anders, J. T. Gudmundsson, D. Lundin
Summary: The magnetic field is a key feature that distinguishes magnetron sputtering from simple diode sputtering. This article analyzes the influence of the magnetic field on electron density and temperature, discharge voltage distribution, and electron heating mechanism in high power impulse magnetron sputtering (HiPIMS) discharges. The results provide insights into adjusting electron density and temperature, as well as their impact on ionization probability.
JOURNAL OF PHYSICS D-APPLIED PHYSICS
(2022)
Article
Chemistry, Physical
Wenjie Wang, Zhongqing Jiang, Xiaoning Tian, T. Maiyalagan, Zhong-Jie Jiang
Summary: Ultra-low amount Pt is uniformly deposited on CoFe nanoparticles embedded nitrogen-doped carbon nanotubes grown directionally on carbon fiber cloth surface using DC-PMS technique. The designed electrode exhibits excellent trifunctional catalytic activities for ORR, HER, and MOR, and shows better catalytic performance and stability than commercial Pt/C catalysts.
Article
Materials Science, Multidisciplinary
Andres Gonzalez-Hernandez, William Aperador, Martin Flores, Edgar Onofre-Bustamante, Juan E. Bermea, Roberto Bautista-Garcia, Federico Gamboa-Soto
Summary: Titanium nitride films exhibit excellent mechanical properties and chemical stability, resulting in resistance to wear and corrosion. This study investigates the influence of deposition parameters on the structure, morphology, composition, and electrochemical behavior of Ti/Ti2N films deposited on carbon steel, with a focus on the substrate temperature.
Article
Environmental Sciences
Pavel Topka, Kvetuse Jiratova, Michaela Dvorakova, Jana Balabanova, Martin Kostejn, Frantisek Kovanda
Summary: This study aimed to develop a novel method for preparing structured Co-Mn mixed oxide catalysts by depositing the active phase on stainless steel meshes through hydrothermal synthesis. The catalysts exhibited significantly higher catalytic activity in ethanol oxidation compared to commercial pelleted Co-Mn-Al catalysts, with the activity correlating with the proportion of surface oxygen vacancies determined by XPS. The exceptional activity of the catalyst with a Co:Mn ratio of 0.5 was attributed to the high number of oxygen vacancies and exceptional redox properties.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Chemistry, Physical
Szabolcs Murath, Natalie Dvornikova, Daniel Moreno-Rodriguez, Radek Novotny, Miroslav Pospisil, Martina Urbanova, Jiri Brus, Frantisek Kovanda
Summary: Anionic drugs atorvastatin and valsartan were successfully intercalated into Mg-Al LDH host with high drug loading. XRD analysis confirmed the intercalation of both drugs, while molecular modeling showed the interaction between drugs and LDH at the atomic scale. Experimental measurements supported the findings from the modeling, indicating weak electrostatic interactions between LDH layers and drug molecules. The release of the drugs from the intercalated LDH slightly differed in different media, following pseudo-second-order kinetics.
APPLIED CLAY SCIENCE
(2023)
Article
Chemistry, Physical
Kveta Kupkova, Pavel Topka, Jana Balabanova, Martin Kostejn, Kvetuse Jiratova, Jean-Marc Giraudon, Jean-Francois Lamonier, Jaroslav Maixner, Frantisek Kovanda
Summary: The effect of Co-Cu oxide catalysts composition on their physicochemical properties and performance in the deep oxidation of ethanol was investigated. The catalysts were characterized and it was found that CuO promoted the reduction of Co3O4. The Co-Cu oxide catalyst with a Co:Cu molar ratio of 4:1 exhibited the best performance in ethanol gas-phase oxidation due to the synergistic effect between Co and Cu components and the presence of finely dispersed CuO particles on the surface of Co3O4.
Article
Chemistry, Physical
Ludek Kaluza, Karel Soukup, Martin Kostejn, Jindrich Karban, Radostina Palcheva, Marek Laube, Daniela Gulkova
Summary: The effects of different supports on the performance of NiMo sulfide catalysts were investigated. It was found that acidic mesoporous SiO2-Al2O3 exhibited higher activity, while activated carbon support showed outstanding stability.
Article
Chemistry, Physical
Kveta Jiratova, Martin Cada, Iryna Naiko, Alina Ostapenko, Jana Balabanova, Martin Kostejn, Jaroslav Maixner, Timur Babii, Pavel Topka, Karel Soukup, Zdenek Hubicka, Frantisek Kovanda
Summary: Hollow cathode plasma sputtering is a beneficial method for preparing catalysts in the form of thin oxide films on supports, which is especially suitable for catalytic total oxidation of volatile organic compounds (VOCs), offering an economically feasible and environmentally friendly approach to VOC abatement.
Article
Biochemistry & Molecular Biology
Karel Soukup, Pavel Topka, Jaroslav Kupcik, Olga Solcova
Summary: This paper reports the preparation of a thermally stable polybenzimidazole electrospun membrane as a support for a platinum catalyst used in the total oxidation of volatile organic compounds. Compared with commercial pelletized catalysts, the membrane with high porosity provides easy accessibility to the platinum active sites and exhibits a low pressure drop. Catalysts with desired platinum particle sizes were obtained by tuning the preparation conditions. The catalyst containing only 0.08 wt.% of platinum achieved high conversion of all model volatile organic compounds at moderate temperatures, which is important for cost reduction of emission abatement technology.
Article
Physics, Fluids & Plasmas
R. Hippler, M. Cada, A. Mutzke, Z. Hubicka
Summary: The study investigates the relationship between the pulse length and discharge characteristics of a reactive HiPIMS discharge with a tungsten cathode in an argon+oxygen gas mixture. The discharge is operated with pulse lengths varying from 20-500 μs. Measurements of discharge current, optical emission spectroscopy, and energy-resolved ion mass spectrometry were conducted. The results show a significant dependence of discharge current on pulse length, as well as a decrease in ion ratios due to target cleaning. Simulation results reveal the formation of a non-stoichiometric sub-surface compound layer, which depends on the impinging ion composition and pulse length.
PLASMA SOURCES SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Kveta Jiratova, Petr Soukal, Anna Kapran, Timur Babii, Jana Balabanova, Martin Kostejn, Martin Cada, Jaroslav Maixner, Pavel Topka, Zdenek Hubicka, Frantisek Kovanda
Summary: A novel method was studied to prepare Ni-Cu oxide catalysts by deposition on stainless steel meshes using hollow cathode plasma jet sputtering. This method allows the preparation of thin oxide films, making the whole volume of the active phase readily accessible for reactants in catalytic reactions. The activity of the sputtered catalyst was significantly higher in ethanol and toluene oxidation compared to the granular catalyst. This outstanding performance was attributed to the synergistic effect between copper and nickel components.
Article
Materials Science, Multidisciplinary
Anna Kapran, Rainer Hippler, Harm Wulff, Jiri Olejnicek, Aneta Pisarikova, Martin Cada, Zdenek Hubicka
Summary: In this experiment, a hollow cathode discharge with a CuNi cathode is used to study the plasma ions in a vacuum chamber with Ar and O2 gases. It is found that Ar+ and O+2 ions are the most abundant species. The deposition rate and heat flux increase with the discharge current, and at high pressures, the directional gas flow further enhances the deposition rate. X-ray diffraction and Raman spectroscopy analysis reveal that the deposited films are composed of a mixed CuxNi1-xO cubic phase with a preferred (111) orientation. Upon annealing, the CuxNi1-xO phase separates into NiO and CuO sub-phases. The annealed films exhibit photoelectrochemical activity as a photocathode, but this activity deteriorates over time due to the reduction of CuO to Cu2O.
