Article
Chemistry, Physical
Burcu Kiren, Nezihe Ayas
Summary: Hydrogen is expected to play a crucial role as an environmentally friendly and flexible energy carrier in future energy systems. This study investigates the effects of catalyst composition and reaction conditions on hydrogen yield in the hydrolysis of NaBH4, and identifies that a catalyst with 40 wt% Ni content exhibits the best performance under specific conditions.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Valentina G. Minkina, Stanislav I. Shabunya, Vladimir I. Kalinin, Vladimir V. Martynenko
Summary: This study investigated the catalytic hydrolysis of aqueous NaBH4 solutions and found that the catalyst used showed stable catalytic activity. It was also observed that conducting the hydrolysis under near adiabatic conditions significantly reduced the hydrolysis time.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Wenkai Huang, Fuhua Xu, Xiang Liu
Summary: Adding nonprecious metal Co or Ni to Ru enhances the H2 generation efficiency synergistically, while alloying with Fe or Cu impedes it. Among them, Co-Ru/C exhibits the highest catalytic activity for H2 generation, with a TOF of 117.69 mol(H2)•molRu-1•min-1, significantly higher than Ru/C's 57.08 mol(H2)•molRu-1•min-1. Moreover, Co-Ru/C shows a TOF of 436.51 mol(H2)•molRu-1•min-1 (96.7 L(H2)•gRu-1•min-1) in the presence of NaOH.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
O. V. Netskina, E. S. Tayban, V. A. Rogov, A. M. Ozerova, S. A. Mukha, V. I. Simagina, O. V. Komova
Summary: In the study, it was found that cobalt catalysts are more active than nickel catalysts in the hydrolysis of sodium borohydride. One reason for the lower activity of nickel catalysts is the presence of hydrogen on its surface, which interferes with reactant adsorption. The addition of cobalt to nickel catalysts can enhance hydrogen generation rate.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Multidisciplinary
Yuqian Yu, Li Kang, Lixian Sun, Fen Xu, Hongge Pan, Zhen Sang, Chenchen Zhang, Xinlei Jia, Qingli Sui, Yiting Bu, Dan Cai, Yongpeng Xia, Kexiang Zhang, Bin Li
Summary: In this study, a porous titanium oxide cage (PTOC) catalyst was successfully synthesized, and its synergistic effect with PtNi alloy particles resulted in a high hydrogen generation rate and low activation energy. The robust porous structure of PTOC effectively prevented agglomeration issues and ensured the long-term stability of the catalyst.
Article
Energy & Fuels
Xiaoteng Min, Dan Chai, Kunpeng Ding, Rui Li, Xiongwen Zhang
Summary: This paper studied the hydrogen generation from the hydrolysis of solid sodium borohydride. A NiCoP/RC catalyst was prepared to accelerate the hydrolysis process. The hydrogen generation rate, reaction temperature, hydrogen output, and water-hydrogen ratio were recorded. Compared to the commonly used cobalt chloride catalyst, the NiCoP/RC catalyst showed superior catalytic activity. The study also discussed the use of citric acid to neutralize alkaline by-products and proposed intermittent water feeding to improve both hydrogen output and water utilization.
Article
Chemistry, Physical
Jifeng Deng, Kurbannisa Kadeer, Chaoyuan Hu, Zewei Xie, Yu Shi, Xiao Liu, Lei Xie, Jinrong Xu, Jie Zheng, Xingguo Li
Summary: In this study, a sponge catalyst for hydrogen generation from liquid hydrogen carriers was developed. The commercial melamine formaldehyde (MF) sponge was modified by grafting polyvinyl alcohol (PVA) through acid-catalyzed acetalization with formaldehyde. The resulting polyvinyl formal/MF (PVF/MF) composite sponge exhibited excellent characteristics as a catalyst, including high activity, high hydrogen storage density, easy catalyst recycling, and quasi-solid state behavior during H-2 generation, as demonstrated in the applications of NaBH4 solution and thermal dehydrogenation of perhydro N-ethylcarbazole.
JOURNAL OF POWER SOURCES
(2023)
Article
Engineering, Environmental
Geo Jong Kim, Hyun Tae Hwang
Summary: Hydrogen from sodium borohydride can be generated by thermolysis or hydrolysis, but both methods have drawbacks such as high temperatures required or safety concerns. A new process, thermal hydrolysis of SBH, is proposed to address these issues and achieve efficient hydrogen production.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Physical
Neslihan Erat, Gamze Bozkurt, Abdulkadir Ozer
Summary: This paper presents the catalytic effect of Co doping on different oxide supports (single, bimetallic, and trimetallic) for the hydrolysis of NaBH4 aqueous solutions. The Co/CuO-NiO-Al2O3 catalyst shows high reaction activity at 25 degrees C and exhibits good reusability.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Minoo Bagheri, Yeganeh Amidi, Mohammad Yaser Masoomi
Summary: In this study, quasi-ZIF-67 (Q-ZIF-67) with large-scale structural defects was synthesized via controlled thermal partial deligandation. Q-ZIF-67 exhibited enhanced catalytic activity for hydrolysis of NaBH4, generating hydrogen at a high rate under mild conditions. Mechanistic studies revealed the importance of strong acidity for efficient hydrogen generation.
Article
Energy & Fuels
Chao Tang, Guolang Zhou, Jianmei Chen, Jingzhou Yin, Yuxin Li, Cheng Liu, Qiaoqi Li, Tianshi Wang, Ziqiang Wang, Shizheng Wen, Benlin Dai, Feihu Mu, Lili Zhang
Summary: Developing nonprecious metal catalysts with fast charge transferability, abundant active sites, and easy recovery is important for hydrogen production from sodium borohydride hydrolysis in alkaline solutions. The magnetically separated nitrogen-doped carbon-supported cobalt oxide (Co x O y @NC) nanoparticles were successfully prepared by converting pyrazine-based covalent organic frameworks (COFs). The Co x O y @NC catalyst exhibited good conductivity and charge transfer ability due to its porous structure and nitrogen-rich characteristics. The H-2 generation rate reached a maximum of 2082.13 mL/min/g from NaBH4, and the catalyst also exhibited good magnetic separation capability.
Review
Chemistry, Physical
Dongyan Xu, Yan Zhang, Qingjie Guo
Summary: This review summarizes recent advances in metallic and nonmetallic catalysts for the alcoholysis of NaBH4, discusses the advantages and disadvantages of various catalysts, and explores the catalytic mechanisms related to NaBH4 methanolysis.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Mohammad Hassan Loghmani, Mona Jalali Rad
Summary: In this study, the use of extracted Glucomannan from Orchis Mascula as a matrix for stable cobalt catalysts in the hydrolysis of sodium borohydride for hydrogen generation was explored. The size, morphology, and activity of Co-glucomannan powders were studied by varying MAA/MBA ratios, with characterization done using XRD, XPS, FE-SEM, and TEM techniques. The catalytic activity of Co-glucomannan was tested on the hydrolysis of sodium borohydride, and kinetic studies were used to determine the partial order respect to catalyst dosage and initial concentration of sodium borohydride. The activation energy of the reaction was calculated using the Arrhenius equation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Thermodynamics
Jae Seon Koh, Do Hoon Kim, Se Hyeok Lee, Min Soo Kim
Summary: The aim of this study was to produce sufficient hydrogen for high-power fuel cell applications through acid-accelerated hydrolysis of sodium borohydride (SBH) with liquid water. The experimental results showed that the conversion of SBH was >= 95%, and a maximum of 6.71 wt% gravimetric hydrogen density was achieved. It was also found that the rate of hydrogen generation could be controlled through the feed injection rate, and the reactant temperature and excess stoichiometric number had significant effects on the hydrogen production.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Chemistry, Physical
Jing Jiang, Shiyu Yang, Huili Lei, Lunhong Ai
Summary: Porous carbon nanostructures as supports can stabilize highly dispersed metal nanoparticles and facilitate mass transfer in reactions; catalytically active porous structures were synthesized and characterized for the efficient catalytic hydrolysis of NaBH4; the prepared Co@NC-600 sample shows high activity due to the catalytically active metallic Co and suitable support effect of N-doped carbon.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Serdar Akbayrak, Gulhan Cakmak, Tayfur Ozturk, Saim Ozkar
Summary: Magnetic isolable ruthenium(0), rhodium(0), and palladium(0) nanoparticles supported on carbon-coated iron particles were synthesized and used as catalysts for hydrolysis of ammonia borane. The catalysts demonstrated high reactivity and turnover frequency at room temperature, showing great potential for industrial applications.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Abhijeet Lale, Maira Debarba Mallmann, Shotaro Tada, Alina Bruma, Saim Ozkar, Ravi Kumar, Masaaki Haneda, Ricardo Antonio Francisco Machado, Yuji Iwamoto, Umit B. Demirci, Samuel Bernard
APPLIED CATALYSIS B-ENVIRONMENTAL
(2020)
Article
Chemistry, Physical
Serdar Akbayrak, Yalcin Tonbul, Saim Ozkar
Summary: The study demonstrates that Rh0/WO3 (0.5% wt. Rh) catalyst shows high catalytic activity in the hydrolysis of ammonia borane, mainly attributed to its reducible nature as the support. Additionally, compared to colloidal(0) nanoparticles, Rh0/WO3 (0.5% wt. Rh) catalyst exhibits better performance in terms of activity, recyclability, and reusability.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Review
Chemistry, Physical
Saim Ozkar
Summary: This review summarizes recent studies on the preparation and use of magnetically separable transition metal nanoparticles (TMNs) as reusable catalysts for the hydrolytic dehydrogenation of ammonia borane (AB). Research includes intrinsically magnetic TMNs, core-shell multimetallic nanoparticles, and TMNs supported on various materials.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Nanoscience & Nanotechnology
Serdar Akbayrak, Saim Ozkar
Summary: The development of a new platinum nanocatalyst with superb catalytic activity and excellent reusability for hydrogen generation from ammonia borane has been reported. The catalyst shows the highest turnover frequency among reported platinum nanocatalysts developed for this purpose.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
Serdar Akbayrak, Saim Ozkar
Summary: In this study, magnetically separable Pt-0/CoFe2O4 nanoparticles were prepared and found to exhibit high catalytic activity and outstanding reusability in the hydrolysis of ammonia borane.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2021)
Article
Chemistry, Physical
Enis Oguzhan Eren, Saim Ozkar
Summary: This review provides an overview of recent advances in developing highly efficient heterogeneous catalysts for the selective electroreduction of CO2 to CO, considering mechanistic investigations and basic catalytic requirements. It compares the efficiency of different combinations of transition metals with various supporting materials, and addresses the current challenges in designing future research in this field.
JOURNAL OF POWER SOURCES
(2021)
Article
Energy & Fuels
Saim Ozkar
Summary: This article reports on how to increase the overall catalytic performance of precious platinum nanocatalysts in the hydrolytic dehydrogenation of ammonia borane. The approaches mentioned include the use of colloidal nanoparticles, supporting the nanoparticles on large surface area materials, selecting suitable oxide support, downsizing the nanoparticles, and using magnetic powder materials as support. These methods can enhance the utilization efficiency and performance of platinum nanocatalysts.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Chemistry, Physical
Berna Sezgin, Yilser Devrim, Tayfur Ozturk, Inci Eroglu
Summary: The most critical development in conventional underwater applications in recent years is the use of hydrogen energy systems, particularly Air Independent Propulsion (AIP) systems powered by Proton Exchange Membrane (PEM) fuel cells. These systems have gained worldwide interest due to their advantages in terms of longer endurance time, silent operation, environmental friendliness, high efficiency, and low thermal dissipation. However, the storage of hydrogen presents a significant challenge in terms of quality, weight, and volume. Different hydrogen storage techniques are required for unmanned underwater vehicles with varying volume and weight requirements.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Chemistry, Physical
Serdar Akbayrak, Saim oezkar
Summary: A new palladium(0) nanocatalyst has been developed to enhance the catalytic efficiency of precious metal catalysts in hydrogen generation from the hydrolytic dehydrogenation of ammonia borane. The catalyst exhibits high activity and superb stability, and has magnetically isolable properties.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Article
Chemistry, Physical
Saim O''zkar, Luke T. Machale, Richard G. Finke
Summary: Synthetic conditions have been discovered to produce massive submicron-sized yet near-uniform Ir-0 particles for the first time. The deliberate addition of Bu3N plays a crucial role in the formation of these particles.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Review
Chemistry, Multidisciplinary
Dogan Akbulut, Saim Ozkar
Summary: This article reviews the catalytic conversion of glycerol to lactic acid in an alkaline medium, discussing the reaction conditions, catalytic activity, and selectivity. The use of different homogeneous and heterogeneous catalysts is discussed, along with proposed mechanisms for glycerol oxidation and the formation of side products.
Review
Chemistry, Inorganic & Nuclear
Saim Ozkar
Summary: This review discusses the progress in developing highly efficient platinum nanocatalysts for the hydrolytic dehydrogenation of ammonia borane, covering various types of platinum-based catalysts and important parameters used in the process, with the ultimate goal of reducing costs and increasing efficiency through future research.
DALTON TRANSACTIONS
(2021)
Review
Materials Science, Multidisciplinary
Christopher B. Whitehead, Saim Ozkar, Richard G. Finke
Summary: The review examines the 1950 model proposing the formation of monodisperse particles and analyzes the experimental support for the concepts of burst/instantaneous nucleation and diffusion-controlled growth. Through a critical look at 164 papers that cited the model since 1950, the review questions the validity of the model's assumptions over the past 70 years.
MATERIALS ADVANCES
(2021)
Article
Electrochemistry
Elif Demir Arabaci, Ahmet M. Onal, Saim Ozkar
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2020)
