Article
Materials Science, Multidisciplinary
Zhi-Nian Li, Hao-Chen Qiu, Xiu-Mei Guo, Jian-Hua Ye, Shu-Mao Wang, Li-Jun Jiang, Jun Du, Fermin Cuevas
Summary: Li-Mg-N-B-H/ZrCoH3 composites were synthesized by ball milling under different atmospheres. The composite synthesized under hydrogen atmosphere displayed the best hydrogen storage properties. The microstructures and elemental distributions were characterized and it was found that Mg underwent in situ hydrogenation and ZrCoH3 particles were homogeneously distributed. The activation energy of the composite was calculated and found to be lower with the addition of ZrCoH3. The weakening of N-H bond was analyzed and discussed.
Article
Chemistry, Physical
A. M. Lakhnik, I. M. Kirian, A. D. Rud
Summary: The Mg/MAX-phase composite materials were synthesized by reactive ball milling in a hydrogen gas atmosphere, and the phase composition and dehydrogenation performance of the composites were investigated. The Ti3AlC2 MAX-phase significantly reduces the dehydrogenation temperature of MgH2, and the highest hydrogen capacity achieved was 5.6 wt%. The kinetic mechanism of the dehydrogenation was investigated using the JMAK technique.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Karina Suarez-Alcantara, Nadia Isabel Flores-Jacobo, Mayara del Pilar Osorio-Garcia, Jose Gerardo Cabanas-Moreno
Summary: In this study, a mixture of Mg-15wt.% VCl3 was prepared by cryogenic ball milling and tested for hydrogen storage. The mixture displayed hydrogen uptake even at near room temperature and achieved about 5 wt.% hydrogen in 1 minute at elevated temperature and pressure. Cryomilling and VCl3 significantly improved the hydriding/dehydriding performance of Mg/MgH2.
Article
Chemistry, Physical
G. N. Churilov, N. S. Nikolaev, V. Elesina, G. A. Glushenko, V. G. Isakova, Ye Tomashevich
Summary: In this study, the change in properties of powders with a core-shell structure (magnesium-carbon and magnesium-carbon/palladium) during the process of hydrogenation/dehydrogenation was investigated. It was found that the decrease in hydrogen sorption capacity was mainly due to the formation of MgO and Mg(OH)2 phases, which hindered the diffusion of hydrogen. The carbon shell provided more complete hydrogenation, while the additional palladium shell increased resistance and lowered the temperature of hydrogenation/dehydrogenation processes.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Eli Grigorova, Pavel Markov, Boyko Tsyntsarski, Peter Tzvetkov, Ivanka Stoycheva
Summary: This study investigates the hydrogen sorption performance of materials based on 80 wt.% MgH2 with the addition of 15 wt.% Ni or V and 5 wt.% activated carbons synthesized from polyolefin wax, a waste product from polyethylene production (POW), walnut shells (CAN), and peach stones (CPS). The composition and performance of the samples are analyzed through milling, hydrogenation, X-ray diffraction, and TEM.
Article
Chemistry, Physical
Fei Song, Jiwei Yao, Hui Yong, Shuai Wang, Xianliu Xu, Yiwan Chen, Lin Zhang, Jifan Hu
Summary: By preparing Mg90Ce3Ni7 alloy through medium-frequency induction melting and mechanical ball-milling process, the study found that ball-milling improves the hydrogen storage performance of the alloy by changing its microstructure. The alloy milled for 20 hours can absorb over 3.5 wt % of hydrogen within 30 minutes at 100 degrees C, indicating its potential for practical applications.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
Yu Liu, Mark Paskevicius, Terry D. Humphries, Craig E. Buckley
Summary: This study demonstrates a one-step ball milling method using Mg2N3 as a reducing agent to regenerate sodium borohydride (NaBH4) from NaBO2$4H2O and produce ammonia gas. This simple process can generate two carbon-free hydrogen carriers suitable for energy export from renewable sources.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Yanshan Lu, Hyunjeong Kim, Keiko Jimura, Shigenobu Hayashi, Kouji Sakaki, Kohta Asano
Summary: This study demonstrates that utilizing the immiscible Mg-Cr system can improve the thermodynamic and kinetic properties of Mg hydrides/deuterides. The formation of nanometer-sized MgD2 domains embedded in a Cr matrix lowers the reaction temperature and reduces the activation energy for hydrogen desorption. This novel strategy of nanostructuring MgH2 by an immiscible matrix shows promise in altering the thermodynamic and kinetic properties for solid-state hydrogen storage applications.
JOURNAL OF POWER SOURCES
(2021)
Review
Energy & Fuels
Adam Revesz, Marcell Gajdics
Summary: Research on hydrogen storage in magnesium-based composites has made significant progress in the past 5 years, with successful applications of various additives and exploration of different catalyst combinations. Ball milling remains a common and effective method in the fabrication process. Enhancements in desorption reactions and hydrogen absorption performance have been achieved, with promising prospects for future research.
Article
Chemistry, Multidisciplinary
Yan Qi, Xin Zhang, Wei Zhang, Jun Li, Zeming Yuan, Shihai Guo, Yanghuang Zhang
Summary: In this study, a quaternary alloy La7Sm3Mg80Ni10 was prepared using casting and ball milling procedures, and the structural changes during hydrogen sorption and desorption were investigated. The results showed that ball milling reduced the grain and particle size and altered their surface properties. Compared to the as-cast alloy, the as-milled alloy absorbed 4 wt% H2 in shorter times at different temperatures. The as-milled and as-cast alloys exhibited similar dehydrogenation enthalpy change (ΔH) and apparent activation energies for dehydrogenation (Ede).
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Chemistry, Physical
F. Khodabakhshi, O. Ekrt, M. Abdi, A. P. Gerlich, M. Mottaghi, R. Ebrahimi, M. Nosko, G. Wilde
Summary: An advanced SPD method called accumulative fold-forging was used to produce layered nanostructured MgNi alloys with superior hydrogen storage capacity. Adjusting the structure can control hydrogen uptake and release characteristics, while refining the grain structure to the nano-scale range can further enhance hydrogen absorption capacity.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
N. N. Sulaiman, M. Ismail, A. H. A. Rashid, N. A. Ali, N. A. Sazelee, S. N. Timmiati
Summary: The hydrogen sorption performances of the 4MgH(2) + LiAlH4 system destabilized with 5 wt% Al2TiO5 showed significantly improved dehydrogenation temperature and kinetics. The introduction of Al2TiO5 resulted in earlier hydrogen liberation and enhanced absorption and desorption kinetics, indicating a synergistic effect on hydrogen storage behavior.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Multidisciplinary
Yan Qi, Peng Sheng, Jun Li, Xin Zhang, Wei Zhang, Shihai Guo, Yanghuan Zhang
Summary: Reducing particle size and modifying surface state by ball milling are effective methods to improve hydrogen absorption kinetics of Mg-based alloys. In this study, ball milling was used to process the as-cast La7Ce3Mg80Ni10 alloy ingot in order to obtain amorphous and nanocrystalline structures. The effects of ball milling time on the structures and the thermodynamics and kinetics of hydrogen absorption/desorption were investigated. The results show that the 10 h-milled alloy exhibits the optimal activation performance and hydrogen absorption/desorption kinetics.
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
(2023)
Article
Energy & Fuels
Nurul Nafiqah Itam Sulaiman, Muhammad Syarifuddin Yahya, Noratiqah Sazelee, Nurul Amirah Ali, Nurul Shafikah Mustafa, Muhammad Firdaus Asyraf Abdul Halim Yap, Mohammad Ismail
Summary: The addition of SrTiO3 significantly improves the hydrogen sorption performance of the 4MgH(2)-Li3AlH6 composite, mainly due to the alteration of its microstructure and pulverization effect. SrTiO3 demonstrates a good catalytic ability to the 4MgH(2)-Li3AlH6 system, reducing the onset decomposition temperature and enhancing rehydrogenation kinetics performance.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Physical
Jiri Cermak, Lubomir Kral, Pavla Roupcova
Summary: The study investigates the effect of the chemical composition of Mg-xCu based alloys modified by KCl on their hydrogen storage performance. It was found that an unknown Cu-rich phase exhibited a catalytic effect on desorption, and the activation energy of hydrogen desorption decreased with increasing Cu content x.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Materials Science, Multidisciplinary
E. M. Paschalidou, F. Celegato, F. Scaglione, P. Rizzi, L. Battezzati, A. Gebert, S. Oswald, U. Wolff, L. Mihaylov, T. Spassov
Article
Pharmacology & Pharmacy
Stiliyana Pereva, Tsveta Sarafska, Svetla Bogdanova, Tony Spassov
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
(2016)
Article
Materials Science, Ceramics
Tony Spassov, Stoyko Gyurov, Georgi Stefanov, Antoan Rangelov, Lyudmil Drenchev, Krassimir Russew
JOURNAL OF NON-CRYSTALLINE SOLIDS
(2016)
Article
Chemistry, Applied
Colin Specht, Robert W. Cattrall, Tony G. Spassov, Maya I. Spassova, Spas D. Kolev
REACTIVE & FUNCTIONAL POLYMERS
(2018)
Article
Nanoscience & Nanotechnology
Stanislava Todorova, Vesselina Rangelova, Veronika Koleva, Tony Spassov
JOURNAL OF NANOMATERIALS
(2019)
Article
Materials Science, Multidisciplinary
Ludmil Drenchev, Tony Spassov, Georgi Stefanov, Akihisa Inoue, Stoyko Gyurov
Article
Chemistry, Physical
Stanislava Todorova, Borislav Abrashev, Vesselina Rangelova, Lyuben Mihaylov, Evelina Vassileva, Konstantin Petrov, Tony Spassov
Summary: The study compared the hydriding/dehydriding properties of LaNi5 based alloys using hydrogen gas phase and electrochemical methods, showing that LaNi4.3Co0.4Al0.3 and LaNi4.8Sn0.2 have higher hydrogen absorption capacities compared to other compositions. Additionally, activated alloys exhibit significantly improved hydriding kinetics, with LaNi4.3Co0.4Al0.3 and LaNi4.8Sn0.2 demonstrating superior performance in electrochemical hydriding/dehydriding behavior.
Article
Chemistry, Physical
Eli Grigorova, Petar Tzvetkov, Stanislava Todorova, Pavel Markov, Tony Spassov
Summary: The composites based on Mg2Ni with 5% activated carbon from apricot stones (ACAP) were prepared by ball milling and subsequent annealing in hydrogen atmosphere. The composites showed relatively high hydrogen storage capacity and fast hydriding/dehydriding kinetics, making them promising materials for hydrogen storage applications.
Article
Thermodynamics
L. Lyubenova, V. Rangelova, M. Spassova, T. Spassov
Summary: A series of Zr-based glasses were obtained by rapid melt quenching and their thermal characteristics were determined. Glass forming ability criteria were applied to predict the glass forming ability of the alloys and study its dependence on the alloy composition. The variation in the glass forming ability was mainly due to difficulties in the crystallization process rather than the stability of the melts.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Electrochemistry
Borislav Abrashev, Valentin Terziev, Stanislava Todorova, Tony Spassov
Summary: This study demonstrates the promising performance of LaNi4.5Co0.4Al0.1 metal hydride electrode, prepared by induction melting and hydrogen-induced decrepitation. The composition and microstructure of the electrode material contribute to its reliable hydrogen capacity and cycle stability. Additionally, the addition of Co3O4 enhances its capacity, making it a suitable electrode material for Ni/MH batteries.
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
(2023)
Article
Polymer Science
Dimitar Shandurkov, Nina Danchova, Tony Spassov, Vesselin Petrov, Roumen Tsekov, Stoyan Gutzov
Summary: A one-pot sol-gel method was developed to incorporate reproducible gold nanoparticles (AuNPs) with sizes of 20-40 nm into SiO2 gels. The AuNPs' chemical composition, optical properties, and size distribution in the gels were affected by variations in the preparation conditions. Organic dopants such as oleic acid, acetic acid, or dodecanethiol were used to modify the composite material and control the reduction and growth rate of the AuNPs in the gels. The synthesized samples were characterized using various methods, including UV/Vis/NIR spectroscopy, X-ray diffraction, transmission electron microscopy, thermal conductivity measurements, and DTA/TG measurements. The incorporation of AuNPs led to an increase in the thermal conductivity of the silica gels. The optimal process involved using NaOH as a gelation catalyst and oleic acid as an organic modifier to disperse 20 nm AuNPs in the silica matrix.
Article
Chemistry, Inorganic & Nuclear
R. I. Tomov, L. Mihaylov, L. R. Bird, Ev. Vassileva, R. V. Kumar, M. Chhowalla, T. Spassov
Summary: A binder- and carbon-free electrode for lithium-ion batteries was prepared using a hierarchically porous Ag-based current collector. The electrode exhibited excellent cycling and rate properties, maintaining high cycling stability even at relatively high current rates.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Inorganic & Nuclear
L. Mihaylov, T. Boyadzhieva, R. Tomov, V Kumar, V Koleva, R. Stoyanova, T. Spassov
DALTON TRANSACTIONS
(2019)
Article
Chemistry, Physical
George Tzvetkov, Nina Kaneva, Tny Spassov
APPLIED SURFACE SCIENCE
(2017)
Article
Multidisciplinary Sciences
Hristina Stoyadinova, Zlatina Zlatanova, Maya Spassova, Vesselina Rangelova, Tony Spassov
COMPTES RENDUS DE L ACADEMIE BULGARE DES SCIENCES
(2016)
Article
Chemistry, Physical
J. Zamora, T. Bautista, N. S. Portillo-Velez, A. Reyes-Montero, H. Pfeiffer, F. Sanchez-Ochoa, H. A. Lara-Garcia
Summary: Experimental and DFT studies were conducted on the structural, magnetic, and optical properties of RFeO3 perovskites. The perovskites exhibited an orthorhombic crystal structure and weak ferromagnetic behavior. They were confirmed to be semiconductors with a bandgap of approximately 2.1 eV.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xianxiang Lv, Jing Jin, Weiguang Yang
Summary: By depositing TiN and TiO2 surface layers on AlSi films, the electrochemical performance of silicon-based anodes can be significantly improved, suppressing volume expansion and promoting the formation of a stable SEI layer.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Sharafat Ali, Haider Ali, Syedul Hasnain Bakhtiar, Sajjad Ali, Muhammad Zahid, Ahmed Ismail, Pir Muhammad Ismail, Amir Zada, Imran Khan, Huahai Shen, Rizwan Ullah, Habib Khan, Mohamed Bououdina, Xiaoqiang Wu, Fazal Raziq, Liang Qiao
Summary: The construction and optimization of redox-heterojunctions using a bifunctional phosphate as an electron-bridge demonstrated significant improvements in photo catalytic activity, including enhanced dispersion, reduced interfacial migration resistance, and increased abundance of active-sites.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ren-Ni Luan, Na Xu, Chao-Ran Li, Zhi-Jie Zhang, Yu-Sheng Zhang, Jun Nan, Shu-Tao Wang, Yong-Ming Chai, Bin Dong
Summary: Extensive research has revealed that oxygen evolution reaction (OER) in alkaline conditions involves dynamic surface restructuring. The development and design of sulfide/oxide pre-catalysts can reasonably adjust the composition and structure after surface reconstruction, which is crucial for OER. This study utilized a simple two-step hydrothermal method to achieve in situ S leaching and doping, inducing the composition change and structure reconstruction of CoFe oxides. The transformed FeOOH and CoOOH exhibited excellent OER activity and could be easily mass-produced using low-cost iron based materials and simple methods.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jun'an Lai, Daofu Wu, Peng He, Kang An, Yijia Wang, Peng Feng, WeiWei Chen, Zixian Wang, Linfeng Guo, Xiaosheng Tang
Summary: Zero-dimensional organic-inorganic metal halides (OMHs) are gaining attention in the fabrication of light-emitting diodes due to their broad emission band and high photoluminescence quantum yield. This work synthesized a zero-dimensional organic tetraphenylphosphonium bismuth chloride (TBC) that showed efficient blue light emission, with the emission mechanism attributed to the transition of Bi3+ ions. White light-emitting diodes (WLEDs) were fabricated using TBC, along with green-emitting and red-emitting single crystals, achieving single-component white emissions. These findings demonstrate the different emission mechanism of ns2 ions-based OMHs and highlight the potential of bismuth-based OMHs in WLEDs applications.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xuewei Liang, Yunhai Su, Taisen Yang, Zhiyong Dai, Yingdi Wang, Xingping Yong
Summary: The revolutionary design concept of high-entropy alloys has brought new opportunities and challenges to the development of advanced metal materials. In this work, AlCrCuFe2NiTix high-entropy flux cored wires were prepared by combining the design idea of a high-entropy alloy with the characteristics of flux cored wire. AlCr-CuFe2NiTix high-entropy surfacing alloys were prepared using gas metal arc welding technology. The wear properties of the alloys were analyzed, and the phase composition, microstructure, strengthening mechanism, and wear mechanism were discussed. The results show that the alloys exhibit a dendritic microstructure with BCC/B2 + FCC phases. Increasing Ti content leads to the precipitation of Laves phase. The alloys show improved microhardness and wear resistance due to the precipitation of coherent B2 and Laves phases. However, excessive Ti addition results in the increase of Laves phase and reduced wear resistance of the alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
M. Vadivel, M. Senthil Pandian, P. Ramasamy, Qiang Jing, Bo Liu
Summary: This work presents the enhanced photocatalytic and electrochemical performance of g-C3N4 assisted PAA on CoFe2O4 ternary nanocomposites. The incorporation of PAA and g-C3N4 improves the separation efficiency of photogenerated charge carriers, resulting in superior photocatalytic degradation and high specific capacitance values.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Vibhu T. Sivanandan, Ramany Revathy, Arun S. Prasad
Summary: In this study, pure and doped cobalt ferrite nanoparticles were prepared using the sol-gel auto-combustion method with the aid of lemon juice as eco-fuel. The crystal structure, lattice parameter, crystallite size, microstrain, optical parameters, and room temperature magnetic properties of the samples were analyzed. The effect of doping on the magnetic properties was also investigated.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qing Guo, Bowen Zhang, Benzhe Sun, Yang Qi
Summary: This study prepared ZnO films with various nonpolar preferred orientations using conventional chemical bath deposition method and characterized their growth process and mechanism. It was found that the type and concentration of nitrate could control the preferred orientation and surface roughness of ZnO films. Additionally, ZnO films with different preferred orientations exhibited different optical properties.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Chong Zhang, Yan Liu, Zhaoyan Wang, Hang Yang
Summary: In this study, six bimetallic FeCo particles were synthesized via the hydrothermal method at different Fe:Co ratios. The Fe:Co ratio not only modulates the composition of the particles but also influences their structure and magnetic properties. The FeCo alloys showed a transformation from an Fe-based structure to a Co-based structure with increasing Co content. The Fe:Co ratio of 1:1 and 3:1 resulted in particles with the highest and lowest saturation magnetization, respectively.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Jianning Zhang, Jing Li, Yiren Wang, Xiaodong Mao, Yong Jiang
Summary: We conducted a study on the formation of ultra-fine Y-Ti-Ta-O nano-oxides in Ta+B micro-alloyed 13CrWTi-ODS alloys using electron microscopy and first-principles calculations. The Y-Ti-Ta-O nano-oxides were found to be mainly Y2(Ti,Ta)2O7, with an average size of 7 nm and a number density of 6.8 x 1023 m-3. Excess boron was found to enhance the adhesion of some low-sigma grain boundaries but weaken the Fe/Y2Ti2O7 interface, while excess tantalum enhanced the Fe/Y2Ti2O7 interface but caused serious degradation of grain boundaries.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Yirong Fang, Pei Cheng, Hang Yuan, Hao Zhao, Lishu Zhang
Summary: A new composite system of nitrogen-doped reduced graphene oxide and black phosphorus quantum dots has been developed for tumor therapy, showing improved electrochemical properties and stability. The system generates hydrogen peroxide and hydroxyl radical to effectively kill tumor cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Xiufang Qin, Yuanli Ma, Hui Zhang, Ting Zhang, Fang Wang, Xiaohong Xu
Summary: The structure and magnetism of cobalt ferrites after Mn2+-Tb3+ co-doping were studied. Co-doped samples exhibited cubic spinel structure and spherical shape of ferrite nanoparticles. The redistribution of Co2+ and Fe3+ ions between octahedral and tetrahedral sites was observed due to Mn2+-Tb3+ co-doping. The coercivity and magnetization saturation of co-doped samples were significantly improved, leading to a maximum energy product that is 190% higher than that of the un-doped sample.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Ho Yeon Lee, Wonjong Yu, Yoon Ho Lee
Summary: Recently, there has been an increasing interest in developing ultra-fine nanostructured electrodes with extensive reaction areas to enhance the performance and low-temperature operation of solid oxide fuel cells. The use of a refined approach involving co-sputtering metal alloys and oxide targets has demonstrated the feasibility of nano-columnar structures in perovskite-based electrodes, expanding the temperature range of thin film electrodes. This study systematically examines the effects of chamber pressure control in the co-sputtering process and identifies the intricate relationship between sputtering pressure and film structure. By fine-tuning the columnar growth in the electrode, significant improvements in performance and thermo-mechanical properties were achieved, resulting in high-performance all-sputtered solid oxide fuel cells.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)
Article
Chemistry, Physical
Qianyun Bai, Xiaoxiao Yan, Da Liu, Kang Xiang, Xin Tu, Yanhui Guo, Renbing Wu
Summary: This study proposes a simple method to develop a non-precious transition metal-based electrocatalyst with high catalytic activity and robustness for the hydrogen evolution reaction. The as-synthesized electrode exhibits a low overpotential and high current density, indicating its potential in energy conversion.
JOURNAL OF ALLOYS AND COMPOUNDS
(2024)