Article
Chemistry, Physical
Hang Che, Yuhao Wu, Xinhua Wang, Haizhen Liu, Mi Yan
Summary: In this work, Li3VO4@LiVO2 was introduced into the Mg(NH2)2-2LiH system to enhance the hydrogen absorption and desorption kinetic characteristics. The addition of 10 wt% Li3VO4@LiVO2 greatly improved the hydrogen storage properties, with significant increase in hydrogen absorption and desorption rates, and decrease in the activation energy of hydrogen desorption. Moreover, Li3VO4@LiVO2 also increased the hydrogen absorption and desorption capacities of the sample.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Luis F. Contreras Vasquez, Yinzhe Liu, David Book
Summary: The synthesis, thermodynamic destabilisation, and hydrogen sorption properties of the M0.2Ca0.8MgH4 hydride system (where M = Na or Li) were investigated in this study. Substitution of Li and Na into Ca-Mg-H ternary hydride caused diffraction peaks to shift to higher angles, and different endothermic reactions were observed.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Chaitanya Gend, Ajay Chaudhari
Summary: Multiple Ti and Li atom doped carbon nanorings were studied for hydrogen storage using density functional theory. The results showed that both Ti and Li doped carbon nanorings were thermodynamically stable and more stable than undoped carbon nanorings. Metal clustering, which reduces hydrogen storage capacity, was not observed in the doped nanorings. The Ti doped carbon nanoring was found to be suitable for hydrogen storage at low temperatures and high pressures, while the Li doped carbon nanoring was not suitable. The hydrogen desorption temperatures for the Ti and Li doped nanorings were 450 K and 113 K respectively, indicating stronger interaction between H2 molecules and Ti doped carbon nanoring.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Chemistry, Physical
V. V. Berezovets, R. Denys, I. Yu Zavaliy, Yu Kosarchyn
Summary: MgH2-based nanocomposites were synthesized using reactive ball milling and various catalytic additives. The additives improved the hydrogen absorption-desorption kinetics and stability of the composites. Nano-Ti showed the most stable hydrogen absorption-desorption characteristics compared to TiO2 and Ti4Fe2Ox additives.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Jingjing Liu, Jie Xu, Salma Sleiman, Xiangyu Chen, Shuai Zhu, Honghui Cheng, Jacques Huot
Summary: The study found that high entropy promotes the formation of BCC phase while large atomic difference has the opposite effect. Among the alloys investigated, V35Ti30Cr25Mn10 showed the highest hydrogen absorption capacity and V35Ti30Cr26Fe5Mn5 exhibited the highest reversible capacity.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
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
Pawan K. Soni, A. Bhatnagar, V Shukla, M. A. Shaz
Summary: Graphene templated Ti-Ni-Fe nanoparticles (TieNieFe@Gr) exhibit excellent catalytic effect on the de/re-hydrogenation characteristics of MgH2, lowering the onset desorption temperature and improving cycling performance. Analysis suggests possible electronic exchange between the catalyst and Mg/MgH2. Anchoring on the graphene template prevents agglomeration that would be detrimental to cycling performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Praphatsorn Plerdsranoy, Palmarin Dansirima, Torben R. Jensen, Rapee Utke
Summary: This study proposes the improvement of de/rehydrogenation kinetics and reversibility of the LiNH2-LiH system by substituting F for H in LiNH2. By combining LiNH2 with excess LiH and compaction, NH3 emission and degradation of hydrogen capacity can be prevented. The formation of LiNH(2-x)Fx achieved from F substitution significantly enhances kinetic properties, and good kinetics and reversibility are preserved even after multiple de/absorption cycles.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Nanoscience & Nanotechnology
Polina Metalnikov, Dan Eliezer, Guy Ben-Hamu
Summary: This study found that the susceptibility to hydrogen embrittlement (HE) differs significantly between Ti?6Al?4V alloys prepared by selective laser melting (SLM) and electron beam melting (EBM). The degradation of SLM Ti?6Al?4V in a hydrogen containing environment is likely to occur through hydride formation and cleavage mechanism, while Ti?6Al?4V prepared by EBM is more likely to degrade through hydrogen enhanced localized plasticity (HELP) mechanism.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
Jorge Montero, Gustav Ek, Martin Sahlberg, Claudia Zlotea
Summary: A novel high entropy alloy containing Mg and refractory elements was prepared through mechanochemical synthesis, showing fast hydrogen absorption and stable cycling properties at room temperature. The addition of Mg significantly enhanced the cycling stability and hydrogen absorption capacity of the alloy, providing important insights for the design of novel high entropy alloys with improved hydrogen storage performance in the future.
SCRIPTA MATERIALIA
(2021)
Review
Chemistry, Physical
Zhi-Xian Wu, Guan-Wen Hu, Yu-Xin Luan
Summary: This review comprehensively summarizes the development of N-hydroxy catalysts, with a special focus on the relationship between structure and performance.
Article
Chemistry, Multidisciplinary
Reshma Babu, Subarna Sukanya Padhy, Rohit Kumar, Ekambaram Balaraman
Summary: Sustainable chemical production requires the development of coherent and robust catalytic systems based on earth-abundant transition metals. This study explores a novel tandem reaction that converts cyclic and acyclic diazo compounds into valuable amines using a single-site molecular manganese complex as the catalyst. The reaction involves dehydrogenation, transfer hydrogenation, and borrowing hydrogenation strategies, and utilizes renewable feedstocks such as alcohols. The synthetic application of this approach in pharmaceutical synthesis and the production of N-CH3/CD3 derivatives is also demonstrated.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Physics, Applied
Mingjie Nie, Yan Ge, Ziyi Liu, Zhicheng Miao, Jiayi Zou, Jiangyi Ding, Zhihong Yang, Huazhong Su, Gang Yan, Yunhui Wang, Lan Bi
Summary: The hydrogen storage performance of Sc (Ti, Li)-modified psi-graphene (psi-g) was investigated using density functional theory. The results show that Sc and Ti can be stably adsorbed on psi-g with high binding energies. In addition, Sc and Ti-modified psi-g can adsorb up to ten and eight hydrogen molecules, respectively, reaching high hydrogen gravimetric storage capacities. Li atoms attached on B-doped psi-g can also adsorb up to eight hydrogen molecules with a high hydrogen gravimetric storage capacity.
INTERNATIONAL JOURNAL OF MODERN PHYSICS B
(2022)
Article
Chemistry, Physical
Md Habibur Rahaman, Usman Yaqoob, Md Mayen Uddin, Hyeon Cheol Kim
Summary: The highly catalytic hydrogen sensing properties of nano percolated Pd/Mg/Ti nanoparticles layers on Si substrate have been investigated. The sensing device shows increased resistance in the presence of hydrogen gas, with a fast response time and stable performance. The sensor has a broad sensing range, fast response time, and good selectivity, making it ideal for hydrogen sensing applications.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Xin Liu, Yang Luo, Hong Ma, Shujing Zhang, Penghua Che, Meiyun Zhang, Jin Gao, Jie Xu
Summary: The study quantitatively characterized hydrogen bonds (HBs) on solid surfaces by measuring the standard Gibbs free energy change (ΔG(0)) using NMR. The research focused on the HB-accepting ability of the surface by comparing ΔG(0) values on a series of Co-N-C-n catalysts with adjustable electron-rich nitrogen-doped contents using the model biomass platform 5-hydroxymethylfurfural. Decreasing ΔG(0) was found to improve the HB-accepting ability of the nitrogen-doped surface, leading to accelerated reaction kinetics and higher turnover frequency (TOF) for oxidation compared to non-noble-metal catalysts.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Materials Science, Multidisciplinary
Jyoti Yadav, M. D. Anoop, Rini Singh, Nisha Yadav, N. Srinivasa Rao, Fouran Singh, Ankur Jain, Takayuki Ichikawa, Kamlendra Awasthi, Manoj Kumar
Summary: In this study, precise and controlled tuning of strain in BiSbTe3 thin films was achieved by Fe ion implantation. The influence of Fe ions on the electronic band structure of BiSbTe3 and the tunability of Fermi level were confirmed by changes in resistivity. The observed reversible tuning of the Fermi level suggests potential device control applications.
Article
Chemistry, Physical
Kentaro Tagawa, Hiroyuki Gi, Keita Shinzato, Hiroki Miyaoka, Takayuki Ichikawa
Summary: This study investigates the reaction properties of ammonia synthesis via the chemical looping process of lithium hydride and proposes a kinetic improvement. The use of lithium oxide as a scaffold significantly improves the reaction kinetics by suppressing product agglomeration. The reaction between lithium hydride and nitrogen can be completed in just 20 minutes with the addition of lithium oxide, compared to more than 1000 minutes without it. Ammonia can be generated at ambient pressure through successive reactions of lithium hydride with nitrogen and hydrogen, which are exothermic processes. The kinetics of the reactions can be controlled by using scaffolds.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Physical
Keita Shinzato, Yuki Nakagawa, Subing Yang, Shigehito Isobe, Tamaki Shibayama, Hiroki Miyaoka, Takayuki Ichikawa
Summary: In this study, hexagonal boron nitride (h-BN) was used for the surface modification of titanium (Ti) to achieve high reactivity for hydrogen (H-2) absorption. The Ti modified by h-BN could absorb approximately 3 wt % of H-2 at 40 degrees C within 10 min and the functional surface was maintained even after dehydrogenation at high temperatures.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Chemistry, Physical
Shashi Sharma, Rini Singh, Takayuki Ichikawa, Ankur Jain, Shivani Agarwal
Summary: Hydrogen as an energy carrier has great potential for future energy infrastructure. The storage of hydrogen in solid state materials, such as KSiH3, has been proposed as a safe method. In this study, vanadium-based catalysts, particularly V2O5, were added to enhance the kinetics and reduce the activation energy of the KSiH3 system. The addition of V2O5 catalyst enabled hydrogen desorption at lower temperatures and achieved a high weight loss close to the theoretical value, indicating improved reversibility and hydrogen storage capacity.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Pratibha Pal, Shivani Agarwal, Ajay Tiwari, Takayuki Ichikawa, Ankur Jain, Ambesh Dixit
Summary: The catalytic effects of exfoliated graphite and graphene nanoballs on the dehydrogenation kinetics of magnesium hydride were investigated. The results showed that the addition of catalysts significantly improved the dehydrogenation kinetics and reduced the activation energy. Graphene nanoballs modified magnesium hydride system exhibited the lowest onset dehydrogenation temperature, indicating better dehydrogenation performance compared to pure magnesium hydride.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Fangqin Guo, Hikaru Oyama, Hiroyuki Gi, Kyohei Yamamoto, Shigehito Isobe, Tomoyuki Ichikawa, Hiroki Miyaoka, Takayuki Ichikawa
Summary: The corrosion of carbide/nitride/oxide-based reactor materials was investigated to address the corrosion problems in sodium redox reactions for thermochemical hydrogen production. Different types of materials were evaluated for their corrosion resistance, and it was found that AlN exhibited the highest resistance among all the nitrides.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
Keita Shinzato, Kentaro Tagawa, Koki Tsunematsu, Hiroyuki Gi, Pankaj Kumar Singh, Takayuki Ichikawa, Hiroki Miyaoka
Summary: The pseudo-catalytic properties of lithium-based alloys with group 14 elements were investigated for ammonia synthesis. The reaction temperature and the formation of products depend on the composition of the alloy, and the metallic feature of lithium species plays a significant role in the reaction. Furthermore, ammonia synthesis can also be achieved at lower temperatures through a catalytic process using a mixture of hydrogen and nitrogen.
ACS APPLIED ENERGY MATERIALS
(2022)
Article
Biochemistry & Molecular Biology
Pranjal Pathak, Kriti Shrivastava, Takayuki Ichikawa, Ankur Jain, Rini Singh
Summary: This paper investigates the issues of solid-state hydrogen absorption systems in hydrogen storage technology, and finds that combining LiNH2 with KH and NaH can lower the hydrogenation temperature. Through thermal and morphological studies, the eutectic phenomenon is observed and a phase diagram is constructed.
Article
Energy & Fuels
Yu Jin, Hongliang Luo, Gengxin Zhang, Chang Zhai, Yoichi Ogata, Yukihiko Matsumura, Takayuki Ichikawa, Yutaka Nakashimada, Wookyung Kim, Keiya Nishida
Summary: Nowadays, reducing carbon emissions is a global concern. To achieve carbon neutrality by the mid-21st century, a regional energy system has been designed to develop a carbon recycling system using fermented gaseous fuels for electricity generation. Hydrogen (H-2) addition is commonly used to improve the efficiency of methane (CH4) combustion in engines. However, the varying ignition timings for maximum brake torque (MBT) and brake thermal efficiency (BTE) have not received much attention. This study examines the effect of ignition timing on CH4 combustion with H-2 addition using experiments conducted on a spark ignition engine. The results show that advancing the ignition timing can achieve higher efficiency when using CH4 alone at higher air ratios (lambda). However, when H-2 is added, retarding the ignition timing results in higher BTE from 10% to 50% H-2 addition. The study also maps the working and optimal regions for the co-combustion of H-2 and CH4 under various conditions.
Article
Chemistry, Physical
Anish Tiwari, Shivani Agarwal, Kriti Shrivastava, Takayuki Ichikawa, Ankur Jain, Rini Singh
Summary: The KSiH3 system has superior hydrogen storage properties, making it a potential material for practical hydrogen storage. However, the activation barrier of the reaction restricts its reversible absorption and desorption of hydrogen at elevated temperatures. Catalysts can be used to enhance its kinetic properties, and in this work, Zr-based catalysts were used to reduce the activation energy.
Article
Chemistry, Physical
Hiroyuki Gi, Yuki Kashiwara, Yuki Itoh, Khushbu Sharma, Norio Ogita, Hiroki Miyaoka, Tomofumi Ogawa, Marolop Simanullang, Laurent Prost, Takayuki Ichikawa
Summary: A systematic study was conducted on the cryogenic H2 adsorption properties below the critical point of H2 on various adsorbents, comparing the density of adsorbed H2 and its temperature dependence with liquid H2. While most studies focus on new porous materials for H2 storage, this study investigated the density of adsorbed H2 below the critical point for metal-organic frameworks, super-activated carbon, and graphene nanoplatelets. It was found that the adsorption of superdense H2 in a monolayer state had a much higher density than liquid H2.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Engineering, Electrical & Electronic
Jyoti Yadav, M. D. Anoop, Nisha Yadav, N. Srinivasa Rao, Fouran Singh, Takayuki Ichikawa, Ankur Jain, Kamlendra Awasthi, Rini Singh, Manoj Kumar
Summary: The effects of Ni7+ ion irradiation on Bi2Te3 thin films synthesized by e-beam evaporation were investigated. The films exhibited a polycrystalline rhombohedral structure. Irradiation caused a decrease in crystallite size and an increase in lattice strain. Raman spectra showed changes in A(1u)(1) modes with ion fluence. Surface roughness decreased due to the formation of nanocrystallites. XPS analysis confirmed the near stoichiometric composition of the films. The resistivity increased with ion fluence, resulting in a crossover behavior from n to p-type carriers. Compensation of bulk charge carriers was observed in the ion-irradiated films by adjusting the Fermi level.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Masakuni Yamaguchi, Tomoyuki Ichikawa, Yoshitsugu Kojima, Hiroki Miyaoka
Summary: In this study, the equilibrium pressure of zirconium phosphate during ammonia ab/desorption was measured using cavity ring-down spectroscopy (CRDS). Two-step equilibrium plateau pressure was observed during the ammonia desorption. Hysteresis in zirconium phosphate at different equilibrium pressures during ammonia desorption and absorption was also observed.
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
Materials Science, Multidisciplinary
Yingtong Lv, Xiang Zhang, Wei Chen, Shunlong Ju, Zhenhua Liu, Guanglin Xia, Takayuki Ichikawa, Tengfei Zhang, Xuebin Yu
Summary: Nano-crystallization of MgH2 as an anode in all-solid-state lithium-ion batteries (ASSLIBs) using LiBH4 as a solid-state electrolyte is applied to improve cycling stability. The self-assembly designed MgH2 electrode on graphene effectively alleviates volume expansion, prevents agglomeration of active substances, improves electron transfer, and enhances electrochemical performance. The study demonstrates reversible capacity of 1214 mAh g-1 after 50 cycles and significantly enhanced cycle life with a capacity of 597 mAh g-1 after 200 cycles at a current density of 400 mA g-1. Full cell investigation also shows great application potential for ASSLIBs.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
