Article
Chemistry, Multidisciplinary
Miranda Martinez, Anil R. R. Chourasia
Summary: The Ti/SnO2 interface was investigated using x-ray photoelectron spectroscopy. Chemical interaction between SnO2 and the titanium overlayer at the interface resulted in the reduction of SnO2 to elemental tin and the oxidation of the titanium overlayer. The interface consisted of elemental Sn, SnO2, elemental titanium, TiO2, and Ti-suboxide. Thermal diffusion of the titanium overlayer was observed in the 200 degrees C samples, leading to complete oxidation of the titanium.
Article
Materials Science, Ceramics
Rahul B. Mane, Ramkrishna Sahoo, Bapathi Kumaar Swamy Reddy, Vijay Ravula, Bharat B. Panigrahi, Pramod H. Borse, Dibyendu Chakravarty
Summary: Thermal decomposition of Ti3GeC2 MAX phase at 1773 K yielded an orange-colored titania powder. X-ray photoelectron spectroscopy and UV-visible Diffuse Reflectance Spectrum studies confirmed the effects of Ge substitutional doping in the titania lattice.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Article
Chemistry, Physical
Sachin Yadav, Sangeeta Sahoo
Summary: Diffusion mediated interaction between metal-substrate assembly at high temperature annealing can lead to the formation of new composite materials. The binary composites of titanium nitride and silicide are observed on sputtered grown Ti films on Si3N4/Si substrate during high vacuum annealing process at temperatures 650 degrees C and above, with the maximum silicide formation observed at 780 degrees C.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Physical
Zhihua Yong, Karl-Magnus Persson, Mamidala Saketh Ram, Giulio D'Acunto, Yi Liu, Sandra Benter, Jisheng Pan, Zheshen Li, Mattias Borg, Anders Mikkelsen, Lars-Erik Wernersson, Rainer Timm
Summary: This study explores the correlation between the physicochemical properties of TiN bottom metal electrode and HfOx/TiN interface and the resistive switching behavior of RRAM devices, aiming to enhance the performance of stack integration. The research demonstrates that the concentration of oxygen vacancies in HfOx layer affects the band bending and the formation of a Schottky barrier, potentially enabling dense, large-scale, and low-power memory integration with the ultra-thin-HfOx/TiN device stack.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Dongpeng Wang, Guang Chen, Anding Wang, Yuxin Wang, Yanxin Qiao, Zhenguang Liu, Zhixiang Qi, Chain Tsuan Liu
Summary: To investigate the correlation between single-crystalline structure and corrosion performance in high-strength TiAl alloys, the electrochemical and surface characterization of Ti-45Al-8Nb dual-phase single crystals and polycrystalline counterparts were compared in NaCl solution. The results showed that the dual-phase single crystals exhibited a lower corrosion rate, higher pitting potential, and a more compact passive film with a higher impedance of charge transfer compared to the polycrystals. This enhanced corrosion resistance can be attributed to the more homogeneous microstructure and composition distribution in the dual-phase single crystals.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2023)
Article
Chemistry, Physical
Pankaj Kumar Singh, Keita Shinzato, Hiroyuki Gi, Takayuki Ichikawa, Hiroki Miyaoka
Summary: This study systematically investigates the catalytic properties of group 4-6 element oxides, including TiO2, ZrO2, HfO2, V2O5, Ta2O5, CrO3, MoO3, and WO3, on magnesium hydride (MgH2). The dispersion of each oxide on the MgH2 surface is achieved through ball-milling. The hydrogen desorption properties are analyzed, and the oxides on MgH2 are characterized structurally and spectroscopically. Among the oxides, TiO2, V2O5, ZrO2, and CrO3 exhibit higher catalytic activity, enabling hydrogen desorption at around 200°C. The dispersion of the oxides on Mg is found to be closely related to the catalytic process, except for MoO3. Multi oxide states, particularly the 2+ and 3+ oxidation states of transition metals, contribute to the high catalytic activity.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Applied
M. Perez-Gonzalez, S. A. Tomas
Summary: Photocatalytic Ag-loaded (TiO2)(0.95)-(ZnO)(0.05) thin films were successfully synthesized using the sol-gel dip-coating method, with the incorporation and surface diffusion of Ag confirmed by secondary ion mass spectrometry measurements. X-ray photoelectron spectroscopy revealed the chemical composition and electronic structure of the samples, confirming the presence of TiO2 and ZnO. The best response in photocatalytic activity was observed in the (TiO2)(0.95)-(ZnO)(0.05) thin films doped with 2 mol% Ag.
Article
Chemistry, Physical
Keishi Akada, Seiji Obata, Koichiro Saiki
Summary: In this study, plasma reduction and nitrogen doping were used to modify graphene oxide (GO), resulting in the removal of various functional groups and the introduction of a large amount of nitrogen content. The plasma treatment showed superior properties compared to thermal reduction, and it has the potential to improve device performance and open up new possibilities for GO applications.
Article
Chemistry, Physical
Yogesh Kumar, S. Tripathi, Mangla Nand, R. Jangir, V. Srihari, A. Das, R. Singh, U. Deshpande, S. N. Jha, A. Arya
Summary: This study investigated the effect of Nd doping on the structural, optical, and electronic properties of lanthanum monazite structure. Pure and Nd-doped LaPO4 powders were prepared and analyzed for their composition, oxidation states, crystal structure, and bandgaps. The results confirmed the successful substitution of Nd in the LaPO4 matrix and provided insights into the local structure using extended X-ray absorption fine structure analysis.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Mauricio Lopez Luna, Janis Timoshenko, David Kordus, Clara Rettenmaier, See Wee Chee, Adam S. Hoffman, Simon R. Bare, Shamil Shaikhutdinov, Beatriz Roldan Cuenya
Summary: The study investigates the structural and chemical evolution of oxide-supported iron nanoparticles during the activation stages and the CO2 hydrogenation reaction, revealing the preferential formation of iron surface oxides under reaction conditions. The results highlight the important role played by the oxide support in the final structure and composition of nanosized catalysts.
Article
Materials Science, Multidisciplinary
Xuebing Bai, Qun Cai, Chaoqun Dang, Jinlong Li
Summary: In this study, TiSiN-Ag coatings were deposited on 304 stainless steel using multi-arc ion plating. The composition and structure of the coatings were characterized, and the tribological behavior was investigated at different temperatures. The results showed that the TiSiN-Ag coating with an Ag concentration of approximately 8.66 at.% exhibited excellent frictional performance at high temperatures (>550°C), which was attributed to the diffusion and oxidation of metallic Ag.
JOURNAL OF MATERIALS SCIENCE
(2022)
Article
Chemistry, Physical
Teodor I. Milenov, Dimitar A. Dimov, Ivalina A. Avramova, Stefan K. Kolev, Dimitar V. Trifonov, Georgi V. Avdeev, Daniela B. Karashanova, Biliana C. Georgieva, Kamen V. Ivanov, Evgenia P. Valcheva
Summary: This study focuses on the evaluation of the influence of chemical treatment on the structure and morphology of carbon phases. The chemical interactions of two types of graphite and carbon black with acetone, toluene, and phenol were studied. Experimental and theoretical methods were used to determine the chemical and phase composition, as well as the morphology and structure. The findings suggest that the treatment of graphite powders and carbon black with acetone, toluene, or phenol can be an effective preliminary stage for their modification and conversion into graphene-like phases.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Deok-Yong Cho, Ki-jeong Kim, Kug-Seung Lee, Michael Lubben, Shaochuan Chen, Ilia Valov
Summary: Thin layers inserted between a metal electrode and a solid electrolyte can modify the transport of mass and charge at interfaces and affect electrode reactions. Incorporating C films in functional materials can alter the host's chemical properties and device functionalities. Using X-ray spectroscopies, it was found that inserting graphene or ultrathin amorphous C layers in a Ta2O5/Ta system can tune its chemical and electronic structures, thereby fundamentally changing the resistive switching functionalities.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Multidisciplinary Sciences
Yaguang Zhu, Jianyu Wang, Shyam Bharatkumar Patel, Chaoran Li, Ashley R. Head, Jorge Anibal Boscoboinik, Guangwen Zhou
Summary: The Mars-van Krevelen mechanism is the foundation for oxide-catalyzed oxidation reactions, and it relies on spatiotemporally separated redox steps. In this study, we demonstrate the tunability of this separation using peroxide species formed by excessively adsorbed oxygen, which modifies the catalytic activity and selectivity of the oxide. By differentiating the chemical functionality between lattice oxygen and peroxide, these results are closely relevant to a wide range of catalytic oxidation reactions using excessively adsorbed oxygen to activate lattice oxygen and tune the activity and selectivity of redox sites.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Xu Li, Keito Horiba, Ryoichi Sugiura, Tomoaki Yamada, Junji Yuhara
Summary: In this study, three different precursor Ba-O films on Pt(1 1 1) were characterized and oxide crystalline approximant (OCA) and oxide quasicrystal (OQC) films were prepared via Ti deposition and annealing. Analysis revealed phase transformation likely follows Ti reduction and Ba oxidation, leading to a change in surface atomic density. Structural models proposed for the OCA and OQC films involve cluster tiling of Ba atoms.
APPLIED SURFACE SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
N. G. Korobeishchikov, I. V. Nikolaev, V. V. Atuchin, I. P. Prosvirin, A. V. Kapishnikov, A. Tolstogouzov, D. J. Fu
Summary: The damage caused by gas cluster ion bombardment on the surface of inorganic single crystals is still unresolved. In this study, the influence of the kinetic energy per atom in the clusters (E/N) on the physicochemical structure of KGd(WO4)2:Nd single crystals was evaluated using XPS, Raman spectroscopy, and XRD techniques. The results showed that high-energy mode with E/N of about 100 eV provides sufficient sputtering efficiency, while low-energy mode with a few eV energy causes minimal surface damage. The subsurface crystal structure remained undamaged after cluster bombardment, but an unexpected increase in relative concentration of O atoms by 12% and depletion of K atoms by a factor of 2 was detected in the subsurface layer of KGd(WO4)2:Nd crystals. The surface sputtering features of inorganic single crystals at different E/N modes are discussed.
MATERIALS RESEARCH BULLETIN
(2023)
Article
Chemistry, Physical
Rinat Taziev, Victor Atuchin
Summary: The surface acoustic wave (SAW) properties of potassium titanyl phosphate (KTiOPO4, KTP) single crystal were evaluated using numerical methods. The phase velocity, electromechanical coupling coefficient, power flow deflection angle, and temperature coefficient of delay (TCD) were determined for different crystal cuts of KTP. It was found that the Z-cut and wave propagation direction along the X + 70 degrees-axis have an electromechanical coupling coefficient of 0.59% and a TCD of 62 ppm/degrees C for SAW, while the Z-cut and wave propagation direction along the X-axis have a pseudo-surface wave (PSAW) characterized by a coupling coefficient of 0.46% and a TCD value of 57 ppm/degrees C. The Bleustein-Gulyaev (BG) wave has TCD values of 35 ppm/degrees C and 41 ppm/degrees C for the Y-cut and X-cut of KTP, respectively.
Article
Chemistry, Multidisciplinary
Timur S. Shamirzaev, Victor V. Atuchin, Vladimir E. Zhilitskiy, Alexander Yu. Gornov
Summary: The study investigates the impact of thermally generated equilibrium carrier distribution on vacancy generation, recombination, and mobility in a semiconductor heterostructure with an undoped quantum well. The different rate of thermally generated equilibrium carriers in layers with different band gaps creates a charge-carrier density gradient in the heterostructure at annealing temperatures. The research reveals that the strong dependence of vacancy formation rate on local charge-carrier density results in nonuniform spatial distribution of charged vacancy concentration. A model considering this effect and the dynamics of nonequilibrium vacancy concentration is developed for vacancy-mediated diffusion during high-temperature annealing.
Review
Biochemistry & Molecular Biology
Elvira V. Sobolevskaya, Oleg A. Shumkov, Mikhail A. Smagin, Andrey E. Guskov, Alexandra V. Malysheva, Victor V. Atuchin, Vadim V. Nimaev
Summary: Chronic obliterating lesions of the arteries of lower extremities, caused by atherosclerosis, lead to chronic ischemia and increase the risk of limb loss and cardiovascular mortality. Percutaneous transluminal balloon angioplasty is a minimally invasive approach for limb revascularization, but restenosis is still possible. Early detection of molecular changes as markers of restenosis can help identify at-risk patients and find ways to inhibit this process.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
Victoria Grossman, Victor Atuchin, Bair G. Bazarov, Aleksandr Aleksandrovsky, Evgeniy Eremin, Alexander Krylov, Natalia Kuratieva, Jibzema G. Bazarova, Nikolai Maximov, Maxim Molokeev, Aleksandr Oreshonkov, Natalia Pervukhina, Nikolay Shestakov
Summary: A new multicationic structurally disordered K5FeHf(MoO4)(6) crystal belonging to the molybdate family is synthesized and its electronic and vibrational properties are characterized. The vibrational spectra are dominated by the MoO4 tetrahedra vibrations, while the lattice modes are observed in a low-wavenumber part of the spectra. The compound exhibits paramagnetic behavior with dominant antiferromagnetic interactions and has direct and indirect optical bandgaps of 2.97 and 3.21 eV, respectively. The narrowing of the bandgap is explained by the presence of Mott-Hubbard optical excitation in the system of Fe3+ ions.
Article
Chemistry, Multidisciplinary
Demid S. Abramkin, Mikhail O. Petrushkov, Dmitrii B. Bogomolov, Eugeny A. Emelyanov, Mikhail Yu. Yesin, Andrey V. Vasev, Alexey A. Bloshkin, Eugeny S. Koptev, Mikhail A. Putyato, Victor V. Atuchin, Valery V. Preobrazhenskii
Summary: In this study, the formation, structural properties, and energy spectrum of self-assembled GaSb/AlP quantum dots (SAQDs) were investigated. The growth conditions for SAQDs were determined on both GaP and GaP/Si substrates. The relaxation of strain in SAQDs on GaP/Si substrates did not affect the luminescence efficiency, while the introduction of dislocations in GaP-based SAQDs led to a quenching of luminescence. The energy spectrum of GaP/Si-based SAQDs was found to be of type II with an indirect bandgap.
Article
Engineering, Chemical
Daria M. Turgunalieva, Alena L. Stalinskaya, Ilya I. Kulakov, Galina P. Sagitullina, Victor V. Atuchin, Andrey V. Elyshev, Ivan V. Kulakov
Summary: The multicomponent reaction of 2-nitroacetophenone, acetaldehyde diethyl acetal, beta-dicarbonyl compound, and ammonium acetate in acetic acid solution yielded 4-methyl-substituted derivatives of previously undescribed 5-nitro-1,4-dihydropyridine. Oxidation of the obtained derivatives resulted in 2,4-dimethyl-5-nitropyridines. This study also introduced the use of acetaldehyde diethyl acetal as a source of acetaldehyde in the synthesis of unsymmetrical 1,4-dihydropyridines, which produced controlled synthesis of unsymmetrical 5-nitro-1,4-dihydropyridines. The proposed multicomponent approach allowed the synthesis of previously undescribed substituted 5(3)-nitropyridines.
Article
Microbiology
Victor V. Atuchin, Lyudmila K. Asyakina, Yulia R. Serazetdinova, Anna S. Frolova, Natalia S. Velichkovich, Alexander Yu. Prosekov
Summary: Heavy-metal contaminants are a significant problem in agriculture, threatening food security due to their high toxicity and ability to accumulate in soils and crops. This study aims to develop a consortium of microorganisms isolated from technogenic sites to address soil restoration in agriculture. Promising strains capable of removing heavy metals were selected, and a consortium (Consortium D) consisting of Achromobacter denitrificans, Klebsiella oxytoca, and Rhizobium radiobacter was found to be the most effective. Consortium D demonstrated the ability to produce phytohormones and remove heavy metals from experimental media. Furthermore, the combined use of Trifolium pratense L. and Consortium D improved the efficiency of phytoremediation. Further research will focus on developing a biological product for land remediation in agriculture.
Article
Chemistry, Inorganic & Nuclear
Ksenia A. Nadeina, Sergey V. Budukva, Yuliya V. Vatutina, Polina P. Mukhacheva, Evgeniy Yu. Gerasimov, Vera P. Pakharukova, Igor P. Prosvirin, Tatyana V. Larina, Oleg V. Klimov, Aleksandr S. Noskov, Victor V. Atuchin
Summary: Among the known synthesis procedures and reagents for unsupported Ni-Mo-W catalysts, there is no consensus about optimal preparation conditions. In this study, Ni-Mo-W precursors were prepared via three different techniques and characterized. The catalytic activity was found to be significantly higher when all active metals are available in a mixed phase. The catalyst prepared by the spray drying method showed the highest activity.
Article
Multidisciplinary Sciences
Yurii N. Zhuravlev, Victor V. Atuchin
Summary: The Raman scattering, infrared absorption, and reflection spectra of four different crystals (BaZnBO3F, BaAlBO3F2, BaZn3BO3F2, and BaZnCO3F2) were studied using the CRYSTAL package. The study showed that the spectra were influenced by the layered structure of the crystals and the symmetry of the crystal lattice.
Article
Chemistry, Multidisciplinary
Timur S. Shamirzaev, Victor V. Atuchin
Summary: The vacancy generation dynamics in doped semiconductor heterostructures with quantum dots (QD) formed in the cationic and anionic sublattices of AlAs is investigated. It is experimentally demonstrated that the vacancy-mediated high temperature diffusion is enhanced or suppressed depending on the location of QDs in the heterostructures. A model is developed to explain the doping effect on the vacancy generation dynamics. Additionally, the impact of nonuniform charge carrier spatial distribution on the vacancy generation and diffusion at high temperatures is revealed.
Article
Optics
Vladimir A. Petrov, Gleb V. Kuptsov, Alyona O. Kuptsova, Victor V. Atuchin, Elena V. Stroganova, Victor V. Petrov
Summary: The research aims to investigate the influence of nonlinear active ions concentration profiles in Yb:YAG laser elements on temperature distribution and wavefront distortions during amplification using sub-kilowatt level diode pumping. A mathematical model is presented for the theoretical study of the amplification process in crystals with cubic crystal system. A detailed comparison of Yb:YAG active elements with different concentration profiles of Yb3+ ions is carried out. It is shown that increasing dopant concentration in the pump beam direction can optimize the temperature profile and reduce thermal-induced wavefront distortions.
Article
Biochemistry & Molecular Biology
Anastasia Dmitrieva, Oksana Kozlova, Victor Atuchin, Irina Milentieva, Anna Vesnina, Svetlana Ivanova, Lyudmila Asyakina, Alexander Prosekov
Summary: The antimicrobial properties of baicalin against H. pylori and several probiotic cultures were evaluated. Baicalin exhibited high antimicrobial activity against H. pylori and a stimulating effect on the growth of certain probiotic strains.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Materials Science, Multidisciplinary
Ana-Elena Tutueanu, Machteld E. Kamminga, Tim B. Tejsner, Henrik Jacobsen, Henriette W. Hansen, Monica-Elisabeta Lacatusu, Jacob Baas, Kira L. Eliasen, Jean -Claude Grivel, Yasmine Sassa, Niels Bech Christensen, Paul Steffens, Martin Boehm, Andrea Piovano, Kim Lefmann, Astrid T. Romer
Summary: We conducted triple-axis neutron scattering studies on strongly underdoped La2-xSrxCuO4 (x = 0.05, 0.06, and 0.07) and presented quantitative evidence for a direct competition between low-energy magnetic fluctuations and superconductivity. Three-dimensional superconductivity was found at x = 0.06 and x = 0.07, while only a weak signal of two-dimensional superconductivity in the CuO2 planes was detected at x = 0.05. Surprisingly, we observed a suppression of the low-energy fluctuations by an external magnetic field at all three doping levels, indicating a similar response of two-dimensional superconductivity to a magnetic field as that of a bulk superconductor. Our results provide direct evidence of a gradual onset of superconductivity in cuprates.
Article
Biotechnology & Applied Microbiology
Larisa Permyakova, Irina Sergeeva, Irina Dolgolyuk, Kseniya Starovoitova, Victor Atuchin, Alexander Vereshchagin, Vasiliy Romanenko, Sergey Lashitsky
Summary: This article investigates the impact of organic acids and ultrasound on the physiological and biochemical properties of yeast in order to obtain bioactive peptides. The study used brewer's yeast S. cerevisiae W-34/70 cultivated in 11% beer wort and activated with a mix of Krebs cycle acids. The ultrasound treatment significantly increased yeast fermentation activity and the activity of enzymes involved in metabolism and proteolysis. Additionally, it enhanced the synthesis of amino acids and proteins, making it easier to extract valuable components.
FERMENTATION-BASEL
(2023)
Article
Chemistry, Physical
Erhao Gao, Wenjing Feng, Qi Jin, Li Han, Yi He
Summary: The influence of K-doping on the reactive oxygen species and elementary reactions of HCHO catalytic oxidation was investigated using density functional theory (DFT). The introduction of K-doping changed the electronic structures of Ce and O, facilitating the adsorption and activation of HCHO and O2 molecules, enhancing lattice oxygen mobility, and reducing the energy barrier for HCHO oxidation. K-doping also promoted the formation of hydroxyl groups, facilitating HCHO adsorption and oxidation.
Article
Chemistry, Physical
Hao Fu, Zhangliang Xu
Summary: In this study, the adsorption mechanisms and detection performance of formaldehyde, ammonia, and sulfur dioxide on undoped and metal-doped ZnO surfaces were investigated using density functional theory. The results showed that formaldehyde and ammonia were physically adsorbed on the undoped ZnO surface, while sulfur dioxide was weakly chemisorbed. The adsorption energy was enhanced when ZnO was doped with metals. These findings provide theoretical guidance for the application of ZnO substrate materials in gas sensitivity research.
Article
Chemistry, Physical
Atsushi Nomura, Tohru Kurosawa, Migaku Oda, Satoshi Demura, Shogo Kuwahara, Sora Kobayashi, Hideaki Sakata
Summary: The study investigates the tunneling spectra of 1T-TiSe2 in the CDW state and the dip structure below the Fermi level, aiming to determine whether this dip is a CDW gap. The answer to this question is crucial for understanding the driving mechanism of CDW.
Article
Chemistry, Physical
A. S. Petrov, D. I. Rogilo, A. I. Vergules, V. G. Mansurov, D. V. Sheglov, A. V. Latyshev
Summary: This study investigates Si mass transport and morphological transformations on the Si(111) surface during (root 3 x root 3)-Sn reconstruction formation and Si homoepitaxy. The research shows that the formation of different Sn phases at different temperatures affects the Si island nucleation and monatomic step shift, which in turn impact the morphology of the Sn/Si(111) interface. Electromigration-induced drift of disordered Sn domains leads to enhanced noncompensated Si mass transport and surface roughening.
Article
Chemistry, Physical
D. V. Gruznev, L. V. Bondarenko, A. Y. Tupchaya, A. A. Yakovlev, A. N. Mihalyuk, A. V. Zotov, A. A. Saranin
Summary: Deposition of thallium (Tl) onto the Au/Si(111)5 x 2 reconstruction followed by annealing results in the formation of a surface structure with 4 x 2 periodicity. The immiscibility of Au and Tl leads to the migration of Tl atoms over the Si chains. Thallium donates electrons to the surface, converting the metallic surface into an insulating state and altering the inter-chain distance within the array of Au atomic wires.
Article
Chemistry, Physical
Simone Giusepponi, Francesco Buonocore, Barbara Ferrucci, Massimo Celino
Summary: Using ab-initio calculations, the interaction between lead adatom and both clean and doped iron (100) surfaces was investigated. It was found that the lead adatom prefers to adsorb in the hollow site, which is more stable compared to the top and bridge sites, and in this position, it is energetically favorable over the iron adatom. Moreover, lead adsorbed in the hollow site of the iron (100) surface doped with chromium was found to create a more stable system compared to nickel-doped surfaces with an iron adatom in the same position. The study also explored inter-layer distances, bonding mechanisms, magnetic behaviors, and charge density differences. The results provide insights into the role of doping in the interaction between lead adatom and iron surface, and have implications for the analysis of corrosion processes caused by liquid lead.
Article
Chemistry, Physical
Shuo Zhang, Jin-Ho Choi
Summary: The recent synthesis of two-dimensional layered WSi2N4 has attracted attention due to its potential applications. This study investigates the catalytic performance of WSi2N4 monolayers with nitrogen vacancies in the hydrogen evolution reaction using first-principles calculations. The results show that the defective WSi2N4 monolayers exhibit remarkably high catalytic activity comparable to platinum catalysts. Electronic structure calculations also reveal the emergence of spin-polarized states due to the introduction of nitrogen vacancies.
Article
Chemistry, Physical
Xiaoyan Yu, Xin Cao, Wei Kang, Shanhua Chen, Ao Jiang, Yuhao Luo, Wenwei Deng
Summary: First-principles calculations were used to investigate the electronic properties of a TiO2 heterostructure modified with Bi2Te3 co-catalyst. The study revealed that the Bi2Te3/TiO2 interface introduced optimal band offsets, effectively suppressing electron-hole recombination and enhancing the utilization efficiency of photo-generated carriers. Additionally, the Bi2Te3 co-catalyst introduced extra catalytic active sites, further boosting the photo-catalytic hydrogen evolution efficiency.
Article
Chemistry, Physical
Filippo Longo, Emanuel Billeter, Selim Kazaz, Alessia Cesarini, Marin Nikolic, Aarati Chacko, Patrik Schmutz, Zbynek Novotny, Andreas Borgschulte
Summary: Alkaline water electrolysis is a simple and efficient method for renewable hydrogen production, utilizing cheap and abundant transition metals. The catalytic properties of Ni materials are enhanced by the formation of oxidized compounds on the surface. The high electrocatalytic activity of Ni (oxy)-hydroxides is directly related to water intercalation in the passivation layer, supporting the hypothesis of a water mediated OH- diffusion mechanism. The self-organization of the surface structure during passivation layer formation enables high electrode performance.
Article
Chemistry, Physical
Mohan Kumar Kuntumalla, Miriam Fischer, Alon Hoffman
Summary: By investigating the bonding, retention, and thermal stability of nitrogen in H-Diamond (100), it was found that nitrogen can partially recover its bonding with carbon atoms after high-temperature annealing, indicating a high thermal stability of nitrogen in diamond.
Article
Chemistry, Physical
Dong Yue, Liangying Wen, Rong Chen, Jianxin Wang, Zhongqing Yang
Summary: The adsorption behavior of Cl2 molecules on the TiC surface and the formation and transfer of reaction products were studied using first-principles ab initio calculations. The results show that the Cl atoms bonded to the surface Ti atoms are more stable, and the TiCl3 intermediate is easier to form than the TiCl2 intermediate.
Article
Chemistry, Physical
Yatao Wang, Peng Zhang, Hongjuan Li, Qiuju Xu, Shujun Liu, Xiaopeng Liu, Xuehua Guo, Yitao Li, Jinzhang Liu, Sen Dong, Zhi Wei Seh, Qianfan Zhang
Summary: In this study, the adsorption performance of two types of metal-organic frameworks (MOFs) for thiophene and benzene was experimentally investigated. The results showed that IZE-1 exhibited high selectivity and superior adsorption capacity for thiophene, especially at low concentrations. First-principles calculations and molecular dynamics simulations provided insights into the mechanism of thiophene adsorption and the high selectivity observed. This research demonstrates the potential of MOFs for thiophene adsorption, particularly at high concentrations.
