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1.
《International Journal of Hydrogen Energy》2022,47(2):1026-1035
In the present study, monazite-type strontium chromate (SrCrO4) as a ternary metal oxide was prepared by the sol-gel method. Nitrogen and sulfur co-doped graphene decorated with SrCrO4 nanocrystals was synthesized successfully, and the electrochemical hydrogen storage performance of the SrCrO4 and its relative nanocomposites also were investigated by chronopotentiometry (CHP) technique. The effect of doped graphene as a substrate of the SrCrO4 sample on the improvement of the electrochemical hydrogen storage performance was considered as well. The SrCrO4-nitrogen and sulfur co-doped graphene (SrCrO4/NSG) displayed the highest discharge capacity in comparison to SrCrO4-reduced graphene oxide (SrCrO4/rGO), SrCrO4 calcined at 1000 °C (SrCrO4 (1000)) and SrCrO4 calcined at 800 °C (SrCrO4 (800)). Also, increasing the hydrogen storage capacity of the samples by repeating the cycles indicated the excellent cycle stability of the nanoparticles. In monazite-type structures, oxygen vacancies can be created by thermal treatment. Creating oxygen vacancies can improve redox reactions, which increase the conductivity of the samples and hydrogen storage capacity. 相似文献
2.
Pistacia Atlantica biomass was utilized as an activated carbon precursor for the preparation of copper oxide/activated carbon (CuO/AC) nanocomposites and the electrochemical hydrogen storage (EHS) capacities of copper oxide with different morphologies and provided nanocomposites were studied. Further, the influence of copper oxide pores size upon the EHS capacity was studied through chronopotentiometry system. Under 1 mA current, the discharge capacities of CuO nanoflowers (CuOnf), CuO nanoparticles (CuOnp), Pistacia Atlantica activated carbon (AC), copper oxide nanoflower/activated carbon (CuOnf/AC), and copper oxide nanoparticle/activated carbon (CuOnp/AC) were reached to 650, 850, 1200, 2000, and 3000 mAh/g after 25 cycles, respectively. Outcomes reveal that the coating of copper oxide upon the AC with different pores size leads to get better discharge capacity. Therefore, produced nanostructures with inexpensive and simple manner can be utilized for EHS and can be applied as Renew. Energy to reduce the use of fossil fuels. 相似文献
3.
《International Journal of Hydrogen Energy》2019,44(23):11979-11988
In this study, oak fruit as a biomass was used to prepare CuO/OBM nanocomposite and the electrochemical hydrogen storage (EHS) capacity of this nanocomposite was investigated. The product was characterized via energy dispersive X-ray analysis (EDX), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and X-ray diffraction (XRD). Then, the effect of CuO/OBM ratio on the electrochemical hydrogen storage was investigated via chronopotentiometry method. After 20 cycles, the discharge capacities of OBM and CuO/OBM nanocomposite under 1 mA current were achieved from 3490 to 5950 mAh/g, respectively. Results show that coating of CuO on the OBM leads to improve the discharge capacity, but by increasing the CuO/OBM ratio, the discharge capacity has been decreased. Results of this study show that produced nanocomposite can be hopeful in replacing of fossil fuel. 相似文献
4.
Fatemeh Sadat Sangsefidi Masoud Salavati-Niasari Mehdi Shabani-Nooshabadi 《International Journal of Hydrogen Energy》2018,43(31):14557-14568
This study proposes a p-type/n-type heterojunction system for electrochemically hydrogen storage. The electrochemical investigation was done as a simple method to evaluate storage capacity. The p-type NiO/n-type CeO2 mesoporous nanocomposites were prepared via a facile thermal decomposition way that is better than the carbohydrates as a green capping agent. For the first time, the electrochemical hydrogen storage behavior of this nanocomposite was evaluated by chronopotentiometry technique in a potassium hydroxide aqueous solution (6 M KOH) under 1 mA current. The electrochemical measurements display that the hydrogen storage capacity is largely dependent on the design of the nanostructures. Sample No. 2 with the plate-like architecture has higher hydrogen storage capacity than sample No. 1 having particle architecture. The plate-like architecture increases the storage capacity by reducing the diffusion pathway, increasing the surface area, and buffering the volume change during cycling. The hydrogen storage capacity for sample No. 1 and 2 was obtained ≈5500 and 6850 mAh/g, respectively. 相似文献
5.
MmMg12–Ni amorphous or nanocrystalline composites (Mm: Ce-rich mischmetal) were prepared through the ball-milling method, and their electrochemical hydrogen storage performance was investigated and compared with that of ball-milled CeMg12–Ni composites. It was found that the ball-milled MmMg12–Ni composites had larger initial discharge capacities and better high rate dischargeability. Analysis of electrochemical impedance spectra (EIS) shows that the reaction resistance and hydrogen diffusion resistance of the ball-milled MmMg12–Ni composites are lower as a result of the decrease in Ce content, and thus can contribute to the larger discharge capacity and better high rate dischargeability. Additionally, the cycle performance of the ball-milled MmMg12–Ni composites is better than those of the ball-milled CeMg12–Ni composites. This may be related to the formation of a Nd oxide or Nd(OH)3 film on surface of the MmMg12 alloys. 相似文献
6.
《International Journal of Hydrogen Energy》2020,45(1):401-411
Cupric chloride is used as oxidant to synthesize polypyrrole doped with inorganic mineral (ImDPpy). The formation of ImDPpy was confirmed by 1HNMR, BET, SEM, HRTEM, DSC, FTIR, Raman, XRD, UV–vis and XPS studies. The surface area calculated for ImDPpy is 36.671 m2/g. Surface area of IMDPpy is 4.671 m2/g higher than the reported value of Ppy in the literature. In DSC, ImDPpy display a peak at 88.07 °C (endothermic glass transition temperature, Tg), Tg of ImDPpy is almost identical to that of Ppy-MWCNT composite and is higher than Tg of undoped Ppy. Electrochemical analysis of ImDPpy in 0.01 M NaOH indicated the maximum charge stored in ImDPpy in the form of protons as 8090 mF/g. The maximum hydrogen storage capacity of ImDPpy is found to be 18mAh/g at an applied current density of 1 mA/cm2. The mineral doped in Ppy during polymerization is identified as [Cu2(OH)3Cl] from XPS and Raman analysis. 相似文献
7.
Rencheng Jin Yanbin Xu Guihua Li Junshen Liu Gang Chen 《International Journal of Hydrogen Energy》2013
Hierarchical chlorophytum-like Bi2S3 nanostructures are produced successfully on the large scale by a solvothermal method in the mixture of water and tetrahydrofuran. The crystal structure and morphology of the product are determined by X-ray diffraction (XRD) pattern, field emission scanning electron microscope (FESEM), and transmission electron microscopy (TEM). Time-dependent SEM observations indicate that the structure evolution of Bi2S3 contains self-assembly process and anisotropic growth mechanism. Furthermore, the electrochemical measurements present that the hierarchical Bi2S3 architectures display high electrochemical hydrogen storage and electrochemical Li intercalation performance. 相似文献
8.
《International Journal of Hydrogen Energy》2019,44(21):10713-10721
Novel nano biomass (NBM) was synthesized using a general and simple synthetic approach. In this process, the walnut shell is used as a green carbon source. According to the transmission electron microscopy and dynamic light scattering results, the average particle size of the produced activated carbon was 2.25 nm. The surface area of the NBM was around 420.5 m2/g totally. High pore volume, high internal surface area, lightweight as well as easy availability are some features that attract research interests on activated carbon as a solid-state hydrogen storage medium. Nano biomass was deposited directly on a copper substrate by the slurry-coating method. The electrochemical properties of nano biomass were investigated in a three-electrode electrolytic cell with 6 M KOH as the electrolyte by galvanostatic charging and discharging. Several parameters such as the impact of the number of charge and discharge cycles and discharge time are studied. Different experimental results show that Cu-NBM has 1596 mAh/g discharge capacity (corresponding to a hydrogen storage capacity of 5.66 wt%) after 16 cycles at room temperature and atmospheric conditions. Due to porosity of NBM particles, the nano biomass showed reversible hydrogen storage capacities that were better than those of previously reported porous carbons. 相似文献
9.
《International Journal of Hydrogen Energy》2019,44(43):24005-24016
In this study, DyMn2O5/Ba3Mn2O8 nanocomposites were prepared by hydrothermal route as potential hydrogen storage materials, for the first time. The effect of hydrothermal reaction time and calcination temperature was considered to achieve the optimum size and morphology. Although the knowledge of hydrogen energy propagated present days, the application of mixed metal oxide nanocomposites as a hydrogen sorbent has not been studied. The prepared nanocomposites with various sizes and morphologies were examined by scanning and transmission electron microscopies (SEM and TEM). X-ray diffraction (XRD), energy dispersive X-ray (EDX) and Fourier transform infrared (FT-IR) were carried out to consider purity and chemical compositions of nanocomposites. Amongst the hydrogen storage routes, electrochemical method is the best because of in situ hydrogen generation and storage at room pressure and temperature conditions. The electrochemical hydrogen storage performance of optimized nanocomposite was investigated in different currents of 0.5 and 1 mA. After 15 cycles, the discharging capacities of nanocomposite in currents of 0.5 and 1 mA were reported 760 and 1600 mAh.g−1, respectively. 相似文献
10.
Fei Liang Jing Lin Yaoming Wu Limin Wang 《International Journal of Hydrogen Energy》2017,42(21):14633-14640
The Ti1.4V0.6Ni doped with NaAlH4 composites were prepared by ball-milling method and the phase composition and electrochemical hydrogen storage properties of the composites were investigated. The phase contains icosahedral quasicrystalline (i-phase), Ti2Ni and V-based solid-solution phase primarily. The NaAlH4 phase is not evident for the composite, and the NaAlH4 phase should be decomposed to help form porous structure on the surface of the composites. The electrochemical hydrogen storage properties of composites has been enhanced with doped NaAlH4, and the maximum electrochemical hydrogen discharge capacity is 299.2 mAh/g, and keeps above 220 mAh/g after 80 cycles for 1 wt.% doping. The high-rate discharge ability of the composite electrode could achieve 79.8% at the discharge current density of 240 mA/g compared with that of 30 mA/g. The enhancement could be attributed to decoration of the composites surface, increase of entropy variation and improvement of H-kinetics on the strength of new porous structure in the composites. 相似文献
11.
Nanocrystalline face-centered cubic (FCC) Co powder encapsulated within graphite layers was fabricated by an arc discharge method. Its electrochemical hydrogenation properties were investigated and compared with those of the hexagonal close packed (HCP) structure. Both exhibited a similar stabilized discharge capacity of approximately 350 mAh/g that can be attributed to the CoHx/Co reaction. During the cyclic charge/discharge, transition between HCP-Co and FCC-Co took place. Graphite encapsulation was beneficial to the cycle stability of the FCC powder. 相似文献
12.
储氢技术作为氢气生产与使用之间的桥梁,至关重要。本文综述了目前常用的储氢技术,主要包括物理储氢、化学储氢与其它储氢。物理储氢主要包括高压气态储氢与低温液化储氢,具有低成本、易放氢、氢气浓度高等特点,但安全性较低。化学储氢包括有机液体储氢、液氨储氢、配位氢化物储氢、无机物储氢与甲醇储氢。其虽保证了安全性,但其放氢难,且易发生副反应,氢气浓度较低。其它储氢技术包括吸附储氢与水合物法储氢。吸附储氢技术的储氢效率受吸附剂的影响较大,且不同程度的存在放氢难、成本高、储氢密度不高等问题。水合物法储氢具有易脱氢、成本低、能耗低等特点,但其储氢密度较低。在此基础上,本文基于现状分析,简要展望了储氢技术今后的研究方向。 相似文献
13.
A layered double hydroxide [Ni4Al(OH)10]OH was doped with different amounts of Zn2+ by coprecipitation and subsequent hydrothermal treatment. The structures of the samples were investigated by XRD, which showed that all are layered double hydroxides with very similar lattice parameters; and samples treated hydrothermally have better crystallinity with ZnO phase. The ZnO exists in rods of several micrometers long, while the [Ni4Al(OH)10]OH in disks of various sizes as shown in SEM images. It has been found that samples treated hydrothermally have higher discharge capacity and better cyclic stability, the maximum discharge capacities are 315 mAh g−1 and 300 mAh g−1 at discharge current densities of 400 mA g−1 and 2000 mA g−1, respectively. 相似文献
14.
《International Journal of Hydrogen Energy》2020,45(3):2135-2144
The effective storage of H2 gas represents one of the major challenges in the wide spread adoption of hydrogen powered fuel cells for light vehicle transportation. Here, we investigate the merits of chemically hydrogenated graphene (graphane) as a means to store high-density hydrogen fuel for on demand delivery. In order to evaluate hydrogen storage at the macroscale, 75 g of hydrogenated graphene was synthesized using a scaled up Birch reduction, representing the largest reported synthesis of this material to date. Covalent hydrogenation of the material was characterized via Raman spectroscopy, X-ray diffraction (XRD), and thermogravimetric analysis (TGA). We go on to demonstrate the controlled release of H2 gas from the bulk material using a sealed pressure reactor heated to 600 °C, identifying a bulk hydrogen storage capacity of 3.2 wt%. Additionally, we demonstrate for the first time, the successful operation of a hydrogen fuel cell using chemically hydrogenated graphene as a power source. This work demonstrates the utility of chemically hydrogenated graphene as a high-density hydrogen storage medium, and will be useful in the design of prototype hydrogen storage systems moving forward. 相似文献
15.
Maryam Karami Mojgan Ghanbari Hassan Abbas Alshamsi Maryam Ghiyasiyan-Arani Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(36):19074-19084
Hydrogen storage is an essential technique for developing hydrogen technology and electrochemical cells in stable energy, transport, and portable power. Hydrogen holds the maximum specific power of all fuels; nevertheless, its low ambient temperature density occurs in a lower energy density; therefore, there is a need to develop advanced storage procedures that own the potential for greater energy density. Therefore, this research incorporates the fabrication of novel nanocomposite (CuI–PbI2) by the sonochemical method, architectural, morphological observations, and relevant electrochemical hydrogen storage features. The electrochemical features with different morphology have revealed 515 and 585 mAh/g discharge capacity for bulk and nano-sized samples after 15 cycles, respectively. 相似文献
16.
The effect of various acids treatment on the purification and electrochemical hydrogen storage of multi-walled carbon nanotubes 总被引:1,自引:0,他引:1
A. Reyhani S.Z. Mortazavi A. Nozad Golikand A.Z. Moshfegh S. Mirershadi 《Journal of power sources》2008,183(2):539-543
The effects of HCl, HNO3, H2SO4 and HF acids on the purification and the electrochemical hydrogen storage of multi-walled carbon nanotubes (MWCNTs) were studied. The MWCNTs were synthesized on Fe–Ni catalyst by thermal chemical vapor deposition method. The X-ray diffraction and thermal gravimetric analysis results indicated that the MWCNTs purified by HF acid had the highest impurities as compared with the other acids. The N2 adsorption results at 77 K indicated that all the samples were mainly mesoporous and the purified MWCNTs by HF acid had the highest surface area as compared with the other acids. The hydrogen storage capacities of the purified MWCNTs by the following acids were in ascending order as: H2SO4, HCl, HNO3 and HF. It was found that the 1–2 nm micropores in the MWCNTs are very important for hydrogen storage. Further, the presences of catalyst and defective sites in MWCNTs influence the hydrogen storage capacity. 相似文献
17.
《International Journal of Hydrogen Energy》2023,48(38):14378-14390
Under ultrasonic irradiation, the porous Tb3Fe5O12 (TFO) and Nickel Aluminum layer double hydroxide (NiAl-LDH) were synthesized by investigation the effect of sonication time. Synthesis of TFO was conducted in the presence of tetradentate Schiff-base ligand H2salophen, [N,N′-bis(salicylidene)-1,2-phenylenediamine] as complexing agent to size controlling and further growth prevention of crystals. The resultant nanocomposites of TFO/NiAl-LDH used as novel active compounds for applying in hydrogen storage strategies. Comprehensively, the hydrogen capacitance after 15 cycles was displayed on the pure NiAl-LDH and TFO materials about 115 and 334 mAhg−1 respectively. It demanded the maximum capacitance for Tb3Fe5O12/NiAl-LDH nanocomposites was 451 mAhg−1, which was higher than the initial NiAl-LDH structure. It was exposed from the spillover effect that; the endorsed electrochemical hydrogen storage (EHS) performance is ascribed to the reaction of the redox pair of Fe3+/Fe2+ at the active sites throughout the EHS procedure. This work delivers a novel plan and potential sorption electrode materials to progress the intrinsic action of layered compounds. 相似文献
18.
Pourya Mehdizadeh Maryam Masjedi-Arani Masoud Salavati-Niasari 《International Journal of Hydrogen Energy》2021,46(33):17253-17266
Nano-sized La–Fe–O (LFO) structures were fabricated via novel free-solvent and green solid-state route using La (acac)3. H2O and Fe (acac)3 complex precursors. Acetylacetonate (acac) in organometallic complex precursors control nucleation and growth of formed crystals with creation spatial barrier around the cations, and prevent nano-product agglomeration. The mechanism of role of acac has been explained in nanostructure formation. Changing of parameters in synthesis reaction consisting La:Fe molar ratio, calcination time and temperature in turn offer a virtuous control over the nanocomposites size and shape which various compositions of La2O3/LaFeO3, LaFeO3/La2O3 and LaFeO3/Fe2O3 obtained. The as-prepared La–Fe–O nano-products were characterized thorough Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), UV–Vis, BET and energy dispersive X-ray (EDX) analysis in terms of crystallinity structure, composition, porosity and morphology. Different formed La–Fe–O nanostructures were evaluated for electrochemical hydrogen storage capacity through chronopotentiometry technique in stable current (1 mA). The achieved La–Fe–O nanoparticles could be applied as a favorable candidate active material for electrochemical hydrogen storage. Optical, magnetic and reducible characteristics of La–Fe–O nanostructures have positive effect on electrochemical hydrogen storage capacity. It was found out that the LaFeO3/Fe2O3 nanocomposites have the best electrochemical hydrogen storage performance due to oxidation-reduction process of Fe2+/Fe3+ components which can help to charge-discharge process of hydrogen to increase the storage capability to 790 mAhg?1 after 20 cycles. Also, the mixed metal oxides illustrate advanced discharge capacity than other binary oxides. 相似文献
19.
《International Journal of Hydrogen Energy》2023,48(72):27944-27959
The world is moving rapidly to embrace renewable energy sources. One energy carrier, hydrogen, is a growing player in this field. This study was motivated by a desire to find alternative hydrogen storage mechanisms using processes that are cost effective with low environmental impact and good energy storage efficiency. This paper presents initial research findings on the novel approach of employing the patented RMIT Proton Battery to store atomic hydrogen in a multilayer graphene electrode using an acid electrolyte. This is a very different approach to conventional hydrogen energy storage systems. The paper reveals that one supplier's product achieves a 0.35 wt% reversible hydrogen storage in a multilayer graphene material with 0.35 nm layer separation and a specific surface area of 720 m2/g. 相似文献
20.
Ananta Kr. Sarkar Shubhanwita Saha Saibal Ganguly Dipali Banerjee Kajari Kargupta 《国际能源研究杂志》2014,38(14):1889-1895
Recently, graphene has received great attention as potential hydrogen storage media. Here, we report a new route to store/chemisorb high content of hydrogen on graphene by employing Benkeser reaction. Graphene nanosheets are produced via a soft chemistry synthetic route involving oxidation of graphite using Improved method, ultrasonic exfoliation, and chemical reduction by using hydrazine with overnight heat treatment. Graphene is hydrogenated by using lithium in ethylenediamine under Benkeser reaction at atmospheric pressure and 30 °C. Benkeser reaction overcomes the liquid ammonia handling and produced multiple layer of graphene attached to the hydrogen atoms. High‐resolution transmission electron microscopy and selected area electron diffraction analysis confirm the ordered graphite crystal structure of graphene and reveal the rough, corrugated hydrogenated graphene layers attached by hydrogen atoms. Fourier transformation infrared spectroscopy analysis confirms that hydrogen adsorption occurs at all the ortho, meta, and para positions of aromatic graphene. The degree of hydrogenation of graphene estimated by thermogravimetric analysis reveals 14.67% (weight %) hydrogen storage, which is considerably higher than the earlier reported values of percentage storage achieved using various physisorption and chemisorption techniques. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献