INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Xuancheng Wang,Xuezhang Xiao,Jiaguang Zheng,Xu Huang,Man Chen,Lixin Chen
The solvent-free amorphous Mg(BH 4 ) 2 composite was in-situ synthesized by ball milling LiBH 4 and MgCl 2 . It is found that the onset dehydrogenation temperature of the as-synthesized composite is 126.9 °C, which is roughly 156 °C lower than that of pristine Mg(BH 4 ) 2 . The activation energy of the amorphous Mg(BH 4 ) 2 and pristine Mg(BH 4 ) 2 for the first dehydrogenation step was calculated as 120.01 kJ/mol and 487.99 kJ/mol, respectively. Hence the kinetics improvement is certified by the lower E a value of the dehydrogenation process. When adding NbF 5 into the composite, the catalyzed composite exhibits better hydrogen storage properties compared to pristine and amorphous Mg(BH 4 ) 2 . The catalyzed composite starts to release hydrogen at proximately 120 °C with a total capacity of 10.04 wt%. The reversibility of the catalyzed composite is also improved. The capacity of the catalyzed composite at the second cycle is 5.5 wt%. For the third and fourth cycles the catalyzed composite can still liberate 4 wt% H 2 . Besides, the onset hydrogen desorption temperature during four cycles are extremely lower than those of pristine and amorphous Mg(BH 4 ) 2 . The peaks of the intermediate MgB 12 H 12 is detected by FTIR as the regenerated hydrogenation product in the catalyzed composite. It can be speculated from the detailed analysis that there are mainly three reasons for the improved properties. Firstly, the additive NbF 5 is favorable to enhance the hydrogen storage properties by modifying the dehydrogenation path and producing MgF 2 and NbB 2 as new products. Secondly, the in-situ formation of amorphous Mg(BH 4 ) 2 is likely to improve the dehydrogenation properties of the samples due to its different reactivity comparing to crystal ones. Finally, LiCl can serve as buffer in the composite and thus improve the dehydrogenation properties.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
iScience
·
2023
·
IF 5.8
Fuhua Xu,Jiaying Yan,Yanlan Wang,Xiang Liu
Sodium formate (SF) is regarded as a technological additive to improve H 2 generation upon HCOOH dehydrogenation. The development of SF as a hydrogen storage material is still a challenge. Herein, we report the design and synthesis of carbon nanosphere-stabilized Pd nanoparticles (Pd/CNS) for the direct H 2 generation upon SF hydrolysis in the presence of Fe 3+ . The tandem reaction, isotopic mass spectrometry, and gas chromatograms result confirmed that SF hydrolysis generates H 2 with one H atom provided by SF and other H by H 2 O. The kinetic study and detailed mechanistic investigations have demonstrated that the concerted process between the cleavage of O-H bond in H 2 O and -O 2 C-H bond oxidative addition is the rate-controlling step in SF hydrolysis. This work offers a new chemical hydrogen storage material (HCOONa) for the high-efficiency generation, transport, and storage of H 2 .
研究领域:
化学
·
能源科学
·
催化科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2019
·
IF 7.723
Weiming Wu,Xiao-Yuan Wu,Sa-Sa Wang,Can-Zhong Lu
H 2 and O 2 were produced at separate times from water electrolysis by using silicotungstic acid as an electron-coupled-proton buffer. It was found that the redox property of silicotungstic acid in water could be regulate by the introduction of organic solvents (acetonitrile, DMF and ethanol). The redox wave of silicotungstic acid at ∼0.02 V vs. RHE moved in the negative direction, which was good for the production of hydrogen. A high yield of hydrogen (∼85%) was obtained in a water-ethanol system (V/V = 1:1), which was higher than that in water (∼45%). And the introduction of ethanol didn’t affect the rate of hydrogen evolution. Moreover, the semihydrogenation of organic compounds could be achieved in the present system under mild conditions. The conversion of phenylacetylene and acetophenone are 97% and 80% under optimum reaction conditions, while the selectivity of styrene and 1-phenylethanol are 80% and 82%, respectively.
研究领域:
化学
·
催化科学
·
能源科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 17
·9996-10005
·
IF 3.119
Xueying Qiu,Jiaxi Liu,Pengru Huang,Shujun Qiu,Chaoming Weng,Hailiang Chu,Yongjin Zou,Cuili Xiang,Fen Xu,Lixian Sun
Ammonia borane (AB, NH3BH3) with extremely high hydrogen content (19.6 wt%) is considered to be one of the most promising chemical hydrides for storing hydrogen. According to the starting materials of AB and H2O, a hydrogen capacity of 7.8 wt% is achieved for the AB hydrolytic dehydrogenation system with the presence of a highly efficient catalyst. In this work, ruthenium nanoparticles supported on magnesium–aluminum layered double hydroxides (Ru/MgAl-LDHs) were successfully synthesized via a simple method, i.e., chemical reduction. The effect of Mg/Al molar ratios in MgAl-LDHs on the catalytic performance for AB hydrolytic dehydrogenation was systematically investigated. Catalyzed by the as-synthesized Ru/Mg1Al1-LDHs catalyst, it took about 130 s at room temperature to complete the hydrolysis reaction of AB, which achieved a rate of hydrogen production of about 740 ml s−1 g−1. Furthermore, a relatively high activity (TOF = 137.1 molH2 molRu−1 min−1), low activation energy (Ea = 30.8 kJ mol−1) and fairly good recyclability of the Ru/Mg1Al1-LDHs catalyst in ten cycles were achieved toward AB hydrolysis for hydrogen generation. More importantly, the mechanism of AB hydrolysis catalyzed by Ru/MgAl-LDHs was simulated via density functional theory. The facile preparation and high catalytic performance of Ru/MgAl-LDHs make it an efficient catalyst for hydrolytic dehydrogenation of AB.
研究领域:
化学
·
材料科学
·
催化
✓ 已验证
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2022
·Vol. 135
·期 5
·2533-2550
·
IF 1.843
Chen Wei,Bao Zhichang,Zhou Zhiming
A series of non-precious bimetallic NiM x /SiO 2 (M = Zn or Co) catalysts with a fixed Ni loading of 5 wt% and different molar ratios of M/Ni (0.004–1.97) were prepared by glucose pyrolysis and applied to the selective hydrogenation of phenylacetylene. The properties of the catalysts were characterized by N 2 physisorption, CO chemisorption, ICP-OES, TGA, XRD, HRTEM, XPS, and DRIFTS. The activity and selectivity of the bimetallic catalysts could be tuned by varying the Zn/Ni and Co/Ni molar ratios, which were almost independent of the metal particle size (with a similar size of 4.1–5.5 nm), but predominantly determined by the geometric and/or electronic effects of the catalysts. Among all the catalysts studied, NiZn 0.05 /SiO 2 and NiCo 0.09 /SiO 2 presented higher selectivity to styrene (86.3% and 88.0%, respectively) at above 99% conversion of phenylacetylene. The high selectivity of the former was attributed to the geometric and electronic effects of the Ni–Zn alloy, while the latter was due to the geometric effect caused by the addition of Co. The activity and selectivity of NiCo 0.09 /SiO 2 were maintained during six consecutive cycles, indicating its good stability in the selective hydrogenation of phenylacetylene.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2020
·Vol. 49
·期 11
·3495-3502
·
IF 4.174
Yu Wang,Zhenmin Ding,Xinjun Li,Shuqin Ren,Shuhua Zhou,Hongming Zhang,Yuan Li,Shumin Han
Magnesium hydride is considered to be one of the most desirable hydrogen storage materials due to its high weight capacity (7.6 wt% H2) and low price. However, its relatively high operating temperatures and slow dynamics have always hampered its commercial applications. In this paper, nano-nickel particle coated nitrogen-doped carbon spheres (Ni@NCS) were synthesized by a chemical reduction method and then introduced into Mg to form an MgH2–Ni@NCS composite via hydriding combustion and subsequent high-energy ball milling processes. The results showed that the MgH2–Ni@NCS composite possessed high hydrogen storage capacity and fast absorbing/desorbing kinetics, absorbing 5.7 wt% H2 and desorbing 4.3 wt% H2 within 8 min at 623 K. Moreover, the capacity shows negligible degradation after 10 cycles, indicating that the MgH2–Ni@NCS composite has good cycling stability. Even at relatively low temperature (373 K), the MgH2–Ni@NCS composite still absorbed 4.2 wt% H2 within 60 min compared to 0.9 wt% H2 for milled MgH2. The improvement in hydrogen storage properties is ascribed to the in situ formed Mg2NiH4 induced dehydrogenation of MgH2 and effective prevention of the agglomeration of magnesium during the hydriding/dehydriding reaction by the carbon material.
研究领域:
材料科学
·
能源化学
·
纳米催化
·
储氢技术
✓ 已验证
DOI
高影响因子
Progress in Natural Science-Materials International
·
2018
·Vol. 28
·期 4
·529-533
·
IF 2.572
Zhenmin Ding,Yufei Ma,Dandan Peng,Lu Zhang,Yumeng Zhao,Yuan Li,Shumin Han
In this work, LiBH 4 –20 wt% PP composite was prepared by ball-milling with as-synthesized hierarchical pyrolysis polyaniline (PP) and LiBH 4 , and the hydrogen sorption performance as well as catalytic mechanism of the composite was studied. It is found that the onset desorption temperature of the composite decreases to 75 °C, almost 235 °C lower than that of the milled LiBH 4 . Moreover, the composite could release 4.1 wt% H 2 and rehydrogenate a total of 4.4 wt% H 2 when the temperature raiseds up to 400 °C, showing an outstanding reversibility, which even 3.9 wt% H 2 can be kept after five cycles. Through scanning electron microscopy (SEM) observation and X-ray diffraction (XRD) analysis, we found that the PP surface forms some nanoholes after hydrogenation-dehydrogenation cycles, which leads to the confinement of some LiBH 4 in the PP nanoporous structure, therefore, the hydrogen sorption kinetics and reversibility are significantly enhanced. In addition, we also found the oxygenic groups of the PP can react with LiBH 4 forming LiBO 2 and Li 3 BO 3 , where the containing Li–B–O bonds loaded in the porous structure of the PP catalyze the hydrogenation reaction of LiBH 4 .
研究领域:
材料科学
·
能源化学
·
纳米材料
·
固态储氢
·
催化化学
✓ 已验证
DOI
高影响因子
Reaction Chemistry & Engineering
·
2019
·Vol. 5
·期 1
·87-100
·
IF 3.935
Chaoquan Hu,Mingyuan Shao,Maoqiao Xiang,Shaofu Li,Shuanghao Xu
Hydrogenation of 1,3-butadiene over supported Pt particles has long been known as a structure sensitive reaction, yet the nature of this phenomenon has not been well understood. We have previously addressed the reaction pathway for 1,3-butadiene hydrogenation over ∼22 nm Pt particles. In this study, the behaviors of SiO2 supported ∼2.9 nm Pt particles towards 1,3-butadiene hydrogenation have been investigated with the aim of providing a fundamental explanation for the structure sensitivity of this reaction. Interestingly, it was found that the product distribution for the present catalyst towards 1,3-butadiene hydrogenation was sensitive to temperature. However, the evolution of 1,3-butadiene hydrogenation over the catalyst with temperature was not captured by in situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. The detected carbonaceous species on the Pt surface are more likely to be spectators rather than reaction intermediates for the formation of butenes and n-butane. To understand the behaviors of the catalyst, density functional theory (DFT) calculations were employed to explore the pathways for the formation of the products with low activation barriers. The results show that the coverage and the location of the hydrogen atom are the two key factors for the interpretation of the behavior of Pt particles towards 1,3-butadiene hydrogenation.
研究领域:
催化化学
·
材料科学
·
理论计算化学
✓ 已验证
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Jin Zhang,Mengting Gao,Pengqi Zhu,Yunwei Wang,Ruiyi Wang,Zhanfeng Zheng
The design of efficient photocatalyst for selective hydrogenation of α,β -unsaturated aldehydes to unsaturated alcohols is changeling. In this study, oxygen vacancy enriched MgAl-layered double hydroxide (MgAl-LDH) supported Co 3 O 4 nanoparticle photocatalysts are developed taking the advantage of the semi-memory effect of CoMgAl-LDH. Excellent photocatalytic performance was achieved with a 99 % cinnamaldehyde conversion and 98 % cinnamyl alcohol selectivity at 100 °C under visible light irradiation. The electron enriched Co 3 O 4 nanoparticles facilitated the activation of isopropanol to provide active H species under light irradiation. In situ DRIFTS and DFT calculation results suggest the oxygen vacancies of MgAl-LDH were beneficial to the terminal O adsorption of –C O group in cinnamaldehyde and ensure the high selectivity of cinnamyl alcohol. This study demonstrated a novel synthesis strategy of Co 3 O 4 nano-photocatalyst for the efficient selective hydrogenation under visible light irradiation.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Hui Liang,Hao Zhang,Yi Zong,Heng Xu,Jun Luo,Xijun Liu,Jie Xu
Doping engineering is an effective strategy to improve the hydrogen storage capacity of magnesium-based materials. Here, we report a magnesium composite containing trace amounts of nickel catalyst (Ni-Mg), in which Ni and Mg layers form a new structural phase. The test shows that Ni-Mg composite has a hydrogen storage capacity of 7.5 wt%, with rapid absorption/desorption kinetics and stable reversible absorption/desorption performance on cycling. Ni-Mg exhibits a superior hydrogen storage performance as compared to the MgNi alloys and Mg-based materials previously reported in the literature. We conclude that a new MgNi phase and MgNi 2 intermetallic compound are formed during the H 2 adsorption process . Based on the theoretical calculations, we show that Ni facilitates hydrogenation by accelerating the dissociation of H 2 molecules into the H atoms, while the MgNi phase formed during the hydrogenation is conducive to the subsequent dehydrogenation, promoting H atoms diffusion between the subsurface and the surface. This work provides a guidance for the development of the efficient hydrogen storage materials .
研究领域:
材料科学
·
能源研究
✓ 已验证
DOI
高影响因子
Energy Technology
·
2018
·Vol. 7
·期 3
·1800533
·
IF 3.175
Shiliang Zhang,Qilu Yao,Qingyang Li,Gang Feng,Zhang-Hui Lu
The synthesis of noble-metal-free recyclable catalysts with prominent catalytic performance for the complete hydrogen production from hydrazine borane (N 2 H 4 BH 3 , HB) is of great significance in achieving a hydrogen economy-based society. Herein, Raney Ni is synthesized using a rapidly quenched aluminum–nickel alloy under a typical alkali leaching condition and is used to catalytically convert hydrogen of N 2 H 4 BH 3 to H 2 via hydrolyzing BH 3 groups and decomposing the N 2 H 4 moiety in alkaline conditions. It is the first report of a noble-metal-free catalyst achieving a complete production of hydrogen from N 2 H 4 BH 3 at room temperature. This noble-metal-free catalyst might tremendously broaden the actual utilization of HB as a promising chemical hydrogen storage material. In addition, such a simple strategy can also be expanded to design and synthesize other porous metals for more applications.
研究领域:
能源化学
·
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS
·
2018
·
IF 1.707
Xiaolu Fan,Yao Zhang,Yunfeng Zhu,Xinli Guo,Jian Chen,Liquan Li
Our previous work found that Li 1.3 Na 1.7 AlH 6 possesses the lowest dehydrogenation onset temperature and the most favorable dehydrogenation thermal stability among Li-Na-Al-H compounds (Fan et al., 2017). In this work, additional Ti 3 C 2 was introduced into Li 1.3 Na 1.7 AlH 6 by ball milling to further enhance its dehydrogenation performances. According to the volumetric release curves, the initial dehydrogenation temperature of the sample Li 1.3 Na 1.7 AlH 6 + 5 wt.%Ti 3 C 2 was lowered by 35 K from that of the pristine Li 1.3 Na 1.7 AlH 6 . The dehydrogenation enthalpy values of Li 1.3 Na 1.7 AlH 6 + 5 wt.%Ti 3 C 2 (46.9 KJ mol H 2 −1 ) was also slightly lower than that of pristine Li 1.3 Na 1.7 AlH 6 (49.7 KJ mol H 2 −1 ). It means that the doped Ti 3 C 2 was actively involved in the reaction with Li 1.3 Na 1.7 AlH 6 during the dehydrogenation process. The investigation by X-ray photoelectron spectroscopy (XPS) demonstrated that the reaction between Ti element and Li 1.3 Na 1.7 AlH 6 was definitely carried out in which the zero valence of Ti was transformed into Ti 3+ .
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）