Journal of Materials Chemistry A
·
2013
·Vol. 1
·期 12
·3983-3991
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IF 0
Lina Chong,Jianxin Zou,Xiaoqin Zeng,Wenjiang Ding
In this work, a reversible hydrogen storage composite, 3NaBH4/NdF3, has been prepared using a mechanical milling method. The de-/rehydrogenation properties as well as the mechanisms of reversible hydrogen sorption in the composite were carefully investigated. Based on the pressure–temperature–composition measurements, the de-/rehydrogenation enthalpies of the 3NaBH4/NdF3 composite are determined to be 86.4 kJ mol−1 H2 and −13.2 kJ mol−1 H2, respectively. The onset dehydriding temperature of the composite is determined to be 413 °C in 0.1 MPa Ar atmosphere and can be as low as 80 °C under vacuum conditions. Analyses revealed that NdB6, Nd2H5 and NaF were formed after the decomposition of the composite, which can be hydrogenated to produce NaBH4 and NaNdF4. The formation of NaNdF4 instead of NdF3 in the hydrogenated products is believed to be responsible for the reduced hydrogen storage capacity, while the intermediate formation of B, Nd and NdB4 during dehydrogenation accounts for the asymmetric hydriding/dehydriding behaviors in the 3NaBH4/NdF3 composite.
研究领域:
材料科学
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化学工程
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DOI
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Jinlin Song,Ran Li,Hua Dong
Numerous catalysts have been widely investigated for accelerating hydrogen production from NaBH 4 hydrolysis. However, these catalysts are usually complicated in structures, costly in fabrication, and hazardous for environment. In this work, cheap and environment-friendly acetic acid, CH 3 COOH, is employed to promote NaBH 4 hydrolysis to produce hydrogen in a considerable rate. The experimental results demonstrate that the addition of suitable amount of CH 3 COOH into NaBH 4 solutions stabilized with NaOH could dramatically accelerate the hydrolysis reaction . Additionally, the start/stop of NaBH 4 hydrolysis could be controlled by adding acid or base into the solution to realize “go-as-you-please” on-site hydrogen production.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Senliang Xi,Xiaojun Wang,Kudzaishe Caren Tome,Tonghuan Zhang,Zongying Han,Meng Gao,Shixue Zhou,Hao Yu
In this work, NaBH 4 +2MgH 2 doped by ZrF 4 was prepared by the ball-milling method. The structure and the morphology of different systems were characterized by X-ray diffraction and scanning electron microscopy. The thermodynamic properties of hydrogen release were determined by temperature-programmed desorption and differential scanning calorimetry . Hydrogen desorption kinetic properties and hydrogen content were investigated by pressure composition isothermal method. The main objective of this work was to study the relationship between the heat of hydrogen release and the quantity of hydrogen released by In-situ calorimetry measurement. The NaBH 4 +2MgH 2 +0.1ZrF 4 can release about 7.4 wt.% H 2 by two steps. Firstly, the heat of hydrogen release of the first and the second steps were lower by 480.82 J·g −1 and 430.8 J·g −1 than that of NaBH 4 +2MgH 2 , respectively. And the dehydrogenation enthalpy of NaBH 4 +2MgH 2 went from −243.81 kJ·mol −1 to −191.2 kJ·mol −1 . Secondly, the addition of ZrF 4 can improve the hydrogen release kinetic property of NaBH 4 +2MgH 2 , which can release 5 wt.% H 2 in 2.5 h at 385 °C under 0.01 MPa hydrogen pressure. Therefore, NaBH 4 +2MgH 2 +0.1ZrF 4 will be a potential candidate as a fuel cell hydrogen supply system.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2024
·
IF 3.2
Shuang Hou,Min Ma,Chun Wang,Peifang Wang,Zhe Ji,Shufang Tian,Mingxue Li
The generation of oxygen vacancies assumes a pivotal role in the photocatalytic degradation of antibiotics. Surface oxygen vacancies serve as deterrents to the recombination of photogenerated carriers, thereby augmenting photocatalytic efficiency. In this work, the NaBH 4 reduction technique was adopted to introduce oxygen vacancies onto the surface of Ta 2 O 5-x , thus enhancing its photocatalytic powers. Remarkably, the photocatalytic activity of the modified Ta 2 O 5-x -0.5 M samples exhibited significant improvement upon treatment with NaBH 4 solution at varied concentrations. Characterization of the modified Ta 2 O 5-x samples was conducted using a suite of techniques including XRD, FT-IR, UV–vis DRS, ESR, XPS, and EPR. Notably, the EPR spectrum provided compelling evidence of the presence of oxygen vacancies, affirming their existence on the surface of the modified Ta 2 O 5-x samples. To further corroborate the formation of oxygen vacancies, tetracycline (TC) solution was employed as a simulated pollutant, revealing a marked enhancement in visible light catalytic activity through experimental observations. The findings elucidate that the defect sites engendered by oxygen vacancies primarily enhance the efficiency of electron-hole pair separation and facilitate greater absorption of visible light, thereby amplifying photocatalytic activity. The modification of Ta 2 O 5-x samples by NaBH 4 reduction predominantly facilitates the introduction of oxygen vacancies on the surface, consequently bolstering photocatalytic performance. This exemplifies a noteworthy approach for significantly enhancing the photocatalytic activity of Ta 2 O 5-x , providing valuable insights for future design strategies.
研究领域:
材料科学
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环境科学
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化学
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DOI
高影响因子
Inorganic Chemistry Frontiers
·
2021
·Vol. 9
·期 2
·370-378
·
IF 6.569
Yongyang Zhu,Hao Zhong,Liuzhang Ouyang,Jiangwen Liu,Hui Wang,Huaiyu Shao,Min Zhu
In this work, we reported an energy-saving and cost-efficient process for the (re)generation of NaBH4 by ball milling hydrated borax (Na2B4O7·10H2O) with a Mg–Al alloy under ambient conditions. The introduction of abundant and readily available Al can increase air stability of the reducing agent. A high yield up to 85.2% could be achieved by using Mg17Al12 because of its hardness and brittleness.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Chong Lu,Jianxin Zou,Xiaoqin Zeng,Wenjiang Ding,Huaiyu Shao
To improve the hydrogen sorption properties of Mg, an arc plasma method with a vacuum vapor deposition technique was used to synthesize a core-shell like structured Mg@NaBH 4 composite. Homogeneously distributed nanoscale NaBH 4 particles can be observed on the surface of Mg matrix according to bright-field scanning transmission electron microscope (BF-STEM) and high-resolution transmission electron microscopy (HRTEM) techniques. A solid solution of Na in Mg might form according to the results of XRD and energy dispersive X-Ray analysis (EDX)-STEM technique. The hydrogenation activation energy ( E a = 60.1 kJ/mol H 2 ) of the Mg in the composite and the onset dehydrogenation temperature for the hydrogenated composite measured from temperature programmed desorption (TPD) (245 °C) were lower than those of pure MgH 2 . The improvement can be ascribed to the core-shell like structure which induces more sufficient contacts between catalysts and Mg, thus providing more nucleation sites for hydrogen sorption. In addition, the formation of MgB 2 and the substitution of Na atoms might support more grain boundaries and cause the changes of electronic structure of Mg/MgH 2 , which can significantly improve the hydrogen sorption properties of Mg. This study implies a novel structure design approach for development of future hydrogen absorption materials.
研究领域:
材料科学
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能源科学
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DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2024
·
IF 3.7
Yunfei Zhao,Hang Sheng,Jiashun Xi,Tingting Jiang,Dong Wang,Jian Zhang,Zheng Li,Bing Wang,Xiaohui Xu,Haifeng Zhang,Bo Yuan,Runlong Hao,Yi Zhao,Tianhao Wang
In the reaction system with NaBH 4 as a hydrogen donor, inhibiting the formation of hydrogen is the key to promote the efficient catalytic hydrogenation of CO 2 . In this study, nanoscale zero-valent nickel supported on carbon nanofibers (Ni 0 /CNFs) was fabricated as a catalyst for CO 2 hydrogenation in aqueous NaBH 4 solution. The characteristics of Ni 0 /CNFs were examined. By SEM, it was observed that spherical nickel nanoparticles were distributed homogeneously on the surface of strip-shaped carbon nanofibers. EDS mappings indicated that elements were evenly distributed on the catalyst, which might contribute to the uniform exposure of active sites. Via XRD, it was determined that all the diffraction peaks corresponded to the crystal face of nickel metal and that the absence of diffraction peaks of carbon nanofibers indicated that the crystallinity of the carrier was low. XPS study showed that nickel existed on the catalyst surface in two forms: zero valence metal and oxidation state. The effects of catalyst addition amount, NaBH 4 concentration, NaOH dosage, stirring rate on the yield of formate and hydrogen generation rate (HGR) were investigated. By optimizing the above parameters, the concentration of formate reached 150 mmol/L and the hydrogen production rate was 10.55 mL/min. Compared with the non-catalytic conditions, the concentration of formate increased by 57 % and the HGR decreased by 78 %. Moreover, the relationship between CO 2 hydrogenation and NaBH 4 hydrolysis was clarified. This research could enhance comprehension of CO 2 hydrogenation in aqueous NaBH 4 solution and contribute to the development of CO 2 capture and utilization storage technology. The significance of this study lies in clarifying the connection between CO 2 hydrogenation and borohydride hydrolysis in CO 2 catalytic hydrogenation technology.
研究领域:
化学工程
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环境科学
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材料科学
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2024
·
IF 5.1
M.O. Abdel-Salam,Youngsoo Kim,Yasser M. Moustafa,Taeho Yoon
Green hydrogen is a crucial element in the hydrogen value chain, encompassing hydrogen production, transportation, storage, and application. The production of green hydrogen via NaBH 4 hydrolysis (SBH) entails a high cost. However, the fast kinetics of this process with a catalyst compensate for the substantial cost, especially in specific applications, such as local or intermittent use. Silver is known for its excellent catalytic properties. Its high catalytic activity is a key factor in achieving efficient hydrogen generation from (SBH). In this study, a nanocomposite catalyst composed of silver nanoparticles (AgNPs), CoFe 2 O 4 , and carbon nanotubes (CNT) was investigated to demonstrate an effective catalyst design approach to achieve enhanced hydrogen generation performance. The H 2 production rate in the presence of Ag-based/CoFe 2 O 4 –CNT was 320 mL min −1 g −1 , and the apparent activation energy was 14.7 kJ mol −1 , superior to that of Ag-based catalysts reported in the literature. Analyses of the observed outcomes revealed that the CNT was decorated with well-dispersed AgNPs and CoFe 2 O 4 nanoparticles. The synergistic effects of AgNPs, CoFe 2 O 4 , and CNT were demonstrated by analyzing the kinetic behaviour of each component based on systematic comparisons. Furthermore, the paramagnetic property of CoFe 2 O 4 enables harvesting of the catalyst using an external magnetic field, and it was verified that the reactivity of the collected catalyst was maintained throughout seven successive cycles. The outstanding catalytic performance of Ag/CoFe 2 O 4 – CNT should be attributed to the uniform dispersion of nanoparticles on the CNT surface. Furthermore, our key approach for developing efficient Ag-based carbon advanced catalysts for SBH in the future is to ensure their suitability for industrial applications.
研究领域:
材料科学
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催化化学
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能源科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Jiale Shen,Danyun Xu,Jian Ji,Qicheng Zhang,Xiaobin Fan
Sodium borohydride (NaBH 4 ) has been proposed to be a realizable hydrogen supplier for proton-exchange membrane fuel cell. Cobalt boride (CoB) is one of the most promising non-precious metal-based catalysts toward NaBH 4 hydrolysis. In this work, we develop a facile method to synthesize defects-rich TiO 2 supported CoB nanoparticles (CoB/TiO 2- x ). In this CoB/TiO 2- x , an electronic metal-support interaction is induced by transferring electrons from the defective TiO 2 to CoB to form electron-rich CoB particles, facilitating the hydrolysis of NaBH 4 . The as-synthesized CoB/TiO 2- x catalyst shows a good catalytic performance with hydrogen generation rate of 3070 mL min −1 g Co −1 and activation energy of 57.03 kJ mol −1 .
研究领域:
材料科学
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催化化学
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DOI
高影响因子
MOLECULES
·
2013
·Vol. 18
·期 10
·12609-12620
·
IF 2.428
Chao Lin,Kai Tao,Dayin Hua,Zhen Ma,Shenghu Zhou
Gold nanoparticles (Au NPs) were prepared by reducing HAuCl4with NaBH4. Their average particle sizes could be tuned in the range of 1.7 and 8.2 nm, by adjusting the amount of NaBH4used during synthesis. The obtained Au NPs (colloids) were then loaded onto a commercial Al2O3support to prepare Au/Al2O3catalysts with tunable Au particle sizes. An optimal pH value (5.9) of the Au colloid solution was found to be essential for loading Au NPs onto Al2O3while avoiding the growth of Au NPs. Au NPs and Au/Al2O3catalysts were tested in the reduction ofp-nitrophenol with NaBH4. Interestingly, the catalytic activity depended on the size of Au NPs, being the highest when the average size was 3.4 nm. Relevant characterization by UV-Vis, TEM, and XRD was conducted.
研究领域:
化学
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材料科学
·
催化
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DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2024
·
IF 3.7
Yugang Shu,Jiaguang Zheng,Chengguo Yan,Ao Xia,Meiling Lv,Zhenxuan Ma,Zhendong Yao
NaBH 4 was widely regarded as a low-cost hydrogen storage material due to its high-mass hydrogen capacity of approximately 10.8% (mass) and high volumetric hydrogen capacity of around 115 g·L –1 . However, it exhibits strong stability and requires temperatures above 500 °C for hydrogen release in practical applications. In this study, two polyhydric alcohols, xylitol and erythritol (XE), were prepared as a binary eutectic sugar alcohol through a grinding-melting method. This binary eutectic sugar alcohol was used as a proton-hydrogen carrier to destabilize NaBH 4 . The 19NaBH 4 -16XE composite material prepared by ball milling could start releasing hydrogen at 57.5 °C, and the total hydrogen release can reach over 88.8% (4.45% (mass)) of the theoretical capacity. When the 19NaBH 4 -16XE composite was pressed into solid blocks, the volumetric hydrogen capacity of the block-shaped composite could reach 67.2 g·L –1 . By controlling the temperature, the hydrogen desorption capacity of the NaBH 4 -XE composite material was controllable, which has great potential for achieving solid-state hydrogen production from NaBH 4 .
研究领域:
材料科学
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化学工程
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DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 28
·9714-9720
·
IF 4
Sirui Liu,Yuxin Shi,Lingling Xu,Weican Zhan,Meixi Chen,Xiaoyue Pan,Yuqing Yao,Jiajie Cai,Mingyi Zhang,Xinzhi Ma
Designing an excellent OER catalyst in an alkaline environment is severe yet essential for industrial H2 application under the electrochemical technique. This study has achieved multiple modifications on CoN nanowires, the classic OER catalyst, via a facile room-temperature NaBH4 spontaneous hydrolysis. This facile process simultaneously generates oxygen vacancies and robust BN species. It wraps hydrophilic BOx motifs on the OER response CoN nanowires, producing OER active Co–N–B species, increasing active numbers and guaranteeing structural stability. It suggests that a low NaBH4 concentration (0.1 mol L−1) treatment endows CoNNWAs/CC with excellent OER performance and robust structure, which can drive a current density of 50 mA cm−2 with only 325 mV overpotentials with more than 24 hours’ durability. Even, the catalyst can drive 1000 mA cm−2 around 480 mV overpotential. This study allows a novel strategy for designing high-performance OER catalysts.
研究领域:
材料科学
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电化学
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催化反应
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DOI
PubMed
高影响因子
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