INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2015
·
IF 3.313
Liuting Zhang,Jiaguang Zheng,Lixin Chen,Xuezhang Xiao,Teng Qin,Yiqun Jiang,Shouquan Li,Hongwei Ge,Qidong Wang
Mg(BH 4 ) 2 is considered as one of the most promising light metal complex hydrides because of its high volumetric and gravimetric hydrogen capacities and world-wide abundance. However, its higher major desorption temperatures (above 300 °C) and poor reaction kinetics have to be improved for the practical application. Herein, Mg(BH 4 ) 2 was successfully synthesized via wet-chemical technique and a significant enhancement in dehydrogenation performance of Mg(BH 4 ) 2 is achieved by the synergetic effect of fluorographite (FGi) and LiBH 4 . Under the effect of FGi, the hydrogen desorption of 6 Mg(BH 4 ) 2 -4FGi composite could be completed below 170 °C in seconds. However, the hydrogen released from 6 Mg(BH 4 ) 2 -4FGi suffers from impurities of B 2 H 6 and HF. More importantly, it is demonstrated that almost all the B 2 H 6 and HF impurities can be suppressed by synergetic modifying Mg(BH 4 ) 2 with FGi and LiBH 4 . The 3 Mg(BH 4 ) 2 –3LiBH 4 -4FGi composite exhibits a capacity over 8.0 wt% H 2 and starts to release hydrogen at 125.7 °C, which is 143.8 °C and 254.3 °C lower than that of pure Mg(BH 4 ) 2 and LiBH 4 , respectively. These significant improvements could be attributed to both the novel morphology that numerous nano-scale borohydride spots formed on the surface of FGi, and the formations of stable fluorides (MgF 2 and LiF) from the interaction between borohydrides and FGi.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Fuel Cells
·
2015
·Vol. 15
·期 2
·270-277
·
IF 2.08
G. R. Li,Q. Q. Wang,B. H. Liu,Z. P. Li
Our study explores the use of porous carbon as anode catalyst support to improve borohydride utilization in a direct borohydride fuel cell. Pt catalysts supported by carbon aerogel (CA) and macroporous carbon (MPC) are synthesized by template method. The pores in porous carbon materials catch hydrogen bubbles to regulate the contact of anolyte with catalytic sites, and this leads to the depression of hydrogen evolution during BH 4 − electrooxidation. However, the hydrogen bubbles in the pores simultaneously deteriorate charge carrier transport and thus increase anode polarization. The CA-supported Pt catalyst improves the coulombic efficiency of BH 4 − electrooxidation. However, the MPC-supported Pt catalyst performed better than the CA-supported Pt catalyst. MPC also has a good pore distribution, which improves the coulombic efficiency of BH 4 − electrooxidation without decreasing anode performance.
研究领域:
材料科学
·
能源技术
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Jinfu Ma,Jing Li,Shaolin Yang,Hui Lu,Limeng Liu,Ruipeng Wang
In direct borohydride fuel cell (DBFC), there is a contradiction between catalytic activity and specific discharge capacity (SDC) owing to the dual catalytic effects of most anode catalysts on both borohydride oxidation reaction (BOR) and borohydride hydrolysis reaction (BHR). To overcome this problem, a facile method to fabricate an ultrathin tin dioxide (SnO 2 ) supported cobalt oxide (Co 3 O 4 ) composite material (u-SnO 2 /Co 3 O 4 ) as DBFC anode catalyst was developed. Both catalytic ability for BOR and specific discharge capacity of the DBFC using the u-SnO 2 /Co 3 O 4 (DBFC-u-SnO 2 /Co 3 O 4 ) with 5–10 nm thick two-dimensional (2D) SnO 2 were improved. The maximum power density (52.5 mW cm −2 ) and SDC (1380 mAh g −1 ) of DBFC-u-SnO 2 /Co 3 O 4 were respectively increased by 105% and 1740% in comparison with those of DBFC with Co 3 O 4 as anode catalyst (DBFC-Co 3 O 4 ). The u-SnO 2 /Co 3 O 4 has higher specific surface area, electron donation ability, and the rate of desorption of intermediate product (such as BH 3 OH − , H ads ) which may account for the excellent catalytic performance of u-SnO 2 /Co 3 O 4 for BOR.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Baoying He,Shuxian Zhuang,Xuefeng Tai,Jinpeng Zhang,Ao Xie,Linting Cheng,Peng Song,Yang Tang,Yongmei Chen,Pingyu Wan
Sodium borohydride is a promising candidate as hydrogen storage material. The direct borohydride fuel cell (DBFC) as an energy conversation device has attracted intensive attention owing to the low theoretical potential of borohydride oxidation reaction (BOR, −1.24 V vs SHE) on the anode. In this paper, the hierarchical sea urchin-like NiMoN@NC coated by thin carbon layer with optimal BH4– adsorption characteristic was synthesized as a superior electrocatalyst toward BOR. In 1 M NaOH-0.05 M NaBH4, the BOR working potentials are only −55 and 44 mV at the current densities of 10 and 200 mA cm–2 on NiMoN@NC, respectively. Furthermore, the membrane-free DBFC using NiMoN@NC as anodic electrocatalyst shows a maximum power density of 67 mW cm–2 at room temperature with appreciative stability. This well-designed carbon coated and nitrogen doped transition-metal material with hierarchical nano/microstructure as a highly efficient electrocatalyst shows promising potential and bright prospects in electrocatalysis research and practical application for energy conversion systems of DBFC.
研究领域:
材料科学
·
电化学
·
能源转换系统
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Jinfu Ma,Xiangyu Gao,Dewei Wang,Tong Xue,Shaolin Yang
The fuel discharging efficiency of direct borohydride fuel cell (DBFC) depends on both the anodic catalyst activity and borohydride hydrolysis. In this paper, Co 3 O 4 anodic catalysts prepared from different cobalt sources used in DBFC have been investigated. It showed that the catalytic performance of Co 3 O 4 was associated with its microstructure that relied on the precursor. The maximum power densities obtained was 40, 62 and 28 mW cm −2 of DBFC with Co 3 O 4 catalyzed anode from CoCl 2 (marked DBFC-A), Co(NO 3 ) 2 (marked DBFC-B) and Co(CH 3 COO) 2 (marked DBFC-C), respectively. The Co 3 O 4 -A has the highest number of electron transfer ( n = 7.06 ) which is close to the theoretical value ( n = 8 ), and DBFC-A showed good voltage stability with specific capacity of 720 mAh.g −1 . A rapid voltage attenuation occurred in DBFC-B with the specific capacity of 330 mAh.g −1 because Co 3 O 4 from Co(NO 3 ) 2 has the higher catalytic activity for both borohydride oxidation reaction (BOR) and hydrolysis which lead to the lower fuel utilization efficiency.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2021
·Vol. 27
·期 35
·9087-9093
·
IF 5.236
Yongyang Zhu,Hao Zhong,Hui Wang,Liuzhang Ouyang,Jiangwen Liu,Zhenguo Huang,Min Zhu
Graphical A cost-effective way to produce NaBH 4 with high yield by ball milling hydrated borax (Na 2 B 4 O 7 ⋅ 10H 2 O) with cheap Al or Al 88 Si 12 at ambient condition is presented. An effective strategy was developed to facilitate mass transfer during the reaction by introducing NaH to enable the formation of loose NaAlO 2 instead of dense Al 2 O 3 on Al surface, and by using Si as a milling additive that prevents agglomeration and also breaks up passivation layers. A significant obstacle in the large-scale applications of sodium borohydride (NaBH 4 ) for hydrogen storage is its high cost. Herein, we report a new method to synthesize NaBH 4 by ball milling hydrated sodium tetraborate (Na 2 B 4 O 7 ⋅ 10H 2 O) with low-cost Al or Al 88 Si 12 , instead of Na, Mg or Ca. An effective strategy is developed to facilitate mass transfer during the reaction by introducing NaH to enable the formation of NaAlO 2 instead of dense Al 2 O 3 on Al surface, and by using Si as a milling additive to prevent agglomeration and also break up passivation layers. Another advantage of this process is that hydrogen in Na 2 B 4 O 7 ⋅ 10H 2 O serves as a hydrogen source for NaBH 4 generation. Considering the low cost of the starting materials and simplicity in operation, our studies demonstrate the potential of producing NaBH 4 in a more economical way than the commercial process.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF POWER SOURCES
·
2018
·
IF 6.945
Hao Zhong,Liuzhang Ouyang,Jiangwen Liu,Chenghong Peng,Xiaoke Zhu,Weiheng Zhu,Fang Fang,Min Zhu
Irreversibility negatively impacts the application of NaBH 4 hydrolysis for hydrogen generation . Byproduct regeneration is key to solving this issue. In this work, the direct byproduct of aqueous NaBH 4 hydrolysis, NaBO 2 ·4H 2 O, is reacted with Mg 2 Si to regenerate NaBH 4 via ball milling at room temperature under an argon atmosphere . In this process, the H − in NaBH 4 is exclusively from the H + in NaBO 2 ·4H 2 O. The regenerated NaBH 4 , with a maximum yield of 74%, has the same physicochemical properties as a commercial sample. We also demonstrate that Mg 2 Si reacts with NaBO 2 ·4H 2 O to generate NaBO 2 ·2H 2 O, followed by a direct reaction between the residual Mg 2 Si and NaBO 2 ·2H 2 O to produce NaBH 4 . The energy efficiency of this method is approximately 40%.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Xuelei Feng,Jianguang Yuan,Yujie Lv,Bogu Liu,Haixiang Huang,Bao Zhang,Youhua Yan,Shumin Han,Ying Wu
Magnesium borohydride (Mg(BH 4 ) 2 ) is an attractive materials for solid-state hydrogen storage due to its high hydrogen content (14.9 wt%). In the present work, the dehydrogenation performance of Mg(BH 4 ) 2 by adding different amounts (10, 20, 40, 60 wt%) of two-dimensional layered Ti 3 C 2 MXene is studied. The Mg(BH 4 ) 2 -40 wt% Ti 3 C 2 composite releases 7.5 wt% hydrogen at 260 °C, whereas the pristine Mg(BH 4 ) 2 only releases 2.9 wt% hydrogen under identical conditions, and the onset desorption temperature decreases from 210 °C to a relative lower temperature of 82 °C. The special layered structure of Ti 3 C 2 MXene and fluorine plays an important role in dehydrogenation process especially at temperatures below 200 °C. The main dehydrogenation reaction is divided into two steps, and activation energy of the Mg(BH 4 ) 2 -40 wt% Ti 3 C 2 composite is 151.3 kJ mol −1 and 178.0 kJ mol −1 , respectively, which is much lower than that of pure Mg(BH 4 ) 2 .
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2019
·
IF 4.084
Chenglei Qin,Liuzhang Ouyang,Hui Wang,Jiangwen Liu,Huaiyu Shao,Min Zhu
Sodium borohydride (NaBH 4 ) is considered to be an excellent hydrogen-generation material via hydrolysis. However, it remains challenge to regenerate it after hydrolysis in practical applications. Therefore, a low-cost regeneration method from hydrolysis by-products for recycling is the key issue. In this study, NaBH 4 was successfully regenerated by direct high-energy ball milling of magnesium alloy (Mg 17 Al 12 ) and hydrolysis by-product NaBO 2 ·2H 2 O with addition of a small amount of NaH. Notably, unlike traditional method, here there is no need of adding extra hydrogen and the H − in the regenerated NaBH 4 is mainly from the H + in the coordinated water. It was found that through adding a small amount of NaH, the highest yield may reach 57% after optimizing the regeneration process. In addition, it is the first time we found that not only Mg can participate in the reaction, but also Al; and the addition of NaH can promote the reaction. Furthermore, the regeneration mechanism of NaBH 4 was analyzed and the transition pattern [B(OH) 4 ] − /[BH 3 (OH)] − /[BH 4 ] − was successfully observed during the regeneration process. It is worth emphasizing that NaBH 4 can be regenerated through ball milling method, which is energy-saving and suitable for up-scaling in the future.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Frontiers in Chemistry
·
2020
·
IF 3.693
Xi Senliang,Wang Xiaojun,Wu Dan,Hu Xingtao,Zhou Shixue,Yu Hao
Phosphotungstic acid (HPW) as a polyoxometalate was selected as the active component of the catalyst. The activated carbon supported different percentage of HPW catalysts were prepared by impregnation and were characterized by X-ray diffraction (XRD), nitrogen adsorption, Fourier transform infrared (FTIR), and scanning electron microscope (SEM). The results showed that the HPW retained the original Keggin structure after being supported on activated carbon, the specific surface of the HPW/C was much bigger than that of pure HPW. The catalytic performance of HPW/C in the hydrogen generation reaction by hydrolysis of sodium borohydride in seawater and in deionized water were studied. 2.5 wt.% HPW/C showed the fastest hydrolysis reaction rate and the biggest volume of hydrogen generated. As for hydrolysis of sodium borohydride, catalytic effect of HPW/C was better in seawater than in distilled water. HPW dispersed on activated carbon is a real promising catalytic system for the development of hydrogen generation by hydrolysis of NaBH4 in seawater.
研究领域:
化学
·
材料科学
·
能源科学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Wenlong Chen,Yuting Chen,Runwei Mo,Jiannong Wang
To reduce the amount of carbon dioxide (CO 2 ) already emitted into the atmosphere, various carbon capture, utilization, and storage (CCUS) technologies have been developed for climate and economic reasons in recent years. However, the state of art CCUS techniques suffer from deficiencies such as high cost, low yield, and harsh and discontinuous production conditions. In this work, we report a new thermal reduction method for continuously conversing CO 2 to methane (CH 4 ) by introducing sodium borohydride (NaBH 4 ) as a reductant under catalyst-free conditions. Experimental results show that CO 2 can be fully captured and converted to CH 4 and carbon monoxide (CO) and the selectivity efficiency of CO 2 to CH 4 can be achieved to be as high as 90% with the optimization of experimental conditions. Such a result originates from the high activity of NaBH 4 and high selectivity of the thermal reduction of CO 2 . To demonstrate one of the potential usages of the reduction products, we integrated the thermal reduction of CO 2 with the production of carbon nanotubes (CNTs). As long as CO 2 is supplied at the source end, the reduction products can undergo catalytic decomposition to produce a CNT fiber or film continuously at the final end. The present technique is featured with simple equipment setup, low cost, and continuous thermal reduction, thus providing a new pathway for the large-scale conversion of CO 2 into high-valued products for wide applications.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2019
·Vol. 7
·期 17
·10723-10728
·
IF 10.733
Hao Zhong,Liuzhang Ouyang,Meiqin Zeng,Jiangwen Liu,Hui Wang,Huaiyu Shao,Michael Felderhoff,Min Zhu
The regeneration of sodium borohydride (NaBH4) is crucial to form a closed cycle after it either supplies hydrogen energy via a hydrolysis process or provides energy through electron transfer at the anode of direct borohydride fuel cells (DBFCs). In both of these cases, the spent fuels are NaB(OH)4 from NaBO2 aqueous solution. However, the current regeneration process from (NaB(OH)4)·xH2O to form NaBH4 by reduction reaction and calcination at high temperature with metal hydrides as reducing agents is very expensive. In this work, we developed a simple regeneration process via ball milling with Mg–Al alloys as the reducing agent for NaB(OH)4 under an argon atmosphere. Under optimized conditions, a high yield of about 72% of NaBH4 could be obtained. Mechanistic study showed that all the hydrogen atoms from NaB(OH)4 remain in NaBH4 and no additional hydrogen sources are needed for the reduction process. The inexpensive Mg–Al alloy works as a reducing agent transforming the H+ to H− in NaBH4. This approach demonstrates a ∼20-fold cost reduction compared with the method using metal hydrides. This opens the door to the commercial implementation of simple ball milling processes for the regeneration of spent NaBH4 from NaB(OH)4 with cheap reducing agents.
研究领域:
化学工程
·
能源材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）