Electrochemical Hydrogen Storage Performances Research Articles

AB-type dual-phase high-entropy alloys as negative electrode of Ni-MH batteries: Impact of interphases on electrochemical performance

High-entropy alloys (HEAs) and their corresponding high-entropy hydrides are new potential candidates for negative electrode materials of nickel-metal hydride (Ni-MH) batteries. This study investigates the cyclic electrochemical hydrogen storage performance of two AB-type HEAs (A: hydride-forming elements, B: non-hydride-forming elements) in Ni-MH batteries. TiV2ZrCrMnFeNi with a dual-phase structure shows a fast activation and a low charge transfer impedance with a discharge capacity of 150 mAhg−1, while TiV1.5Zr1.5CrMnFeNi with a single phase shows a slow activation and a capacity of only 60 mAhg−1. The better electrochemical performance of TiV2ZrCrMnFeNi was attributed to its higher vanadium/zirconium ratio and abundant interphase boundaries, which act as hydrogen paths and heterogeneous hydride nucleation sites. These results suggest the high potential of dual-phase HEAs as new active electrode materials for Ni-MH batteries.

Preparation of Co/Ni nanoparticles doped g-C3N4 for improving the electrochemical hydrogen storage performance of Co0.9Cu0.1Si alloy

A facile liquid-phase reduction strategy was used to prepare cobalt and nickel nanoparticles doped graphitic carbon nitride (g-C3N4). Co0.9Cu0.1Si alloy was manufactured by mechanical alloying. Subsequently, a series of g-C3N4, Co-g-C3N4 and Ni-g-C3N4 modified Co0.9Cu0.1Si composites were fabricated via ball milling. The electrochemical hydrogen storage behaviors of metal doped g-C3N4/Co0.9Cu0.1Si composite electrodes were studied for the first time. Ultimately, Co0.9Cu0.1Si + Co-g-C3N4 and Co0.9Cu0.1Si + Ni-g-C3N4 revealed preferable discharge capacity of 575.8 mA h/g and 561.0 mA h/g than Co0.9Cu0.1Si + g-C3N4 and conventional Co0.9Cu0.1Si electrodes. The g-C3N4 offered more electrochemical active sites and beneficial interface for charge transfer. The metal particles within g-C3N4 further improved the electrocatalytic activity. The metal nanoparticles and g-C3N4 played synergistic effect in enhancing the hydrogen diffusion and electrochemical behavior of Co0.9Cu0.1Si alloy. Moreover, Co-g-C3N4 and Ni-g-C3N4 modified Co0.9Cu0.1Si also demonstrated better capacity retention, high-rate dischargeability (HRD) and kinetics properties. Accordingly, Co/Ni nanoparticles doped g-C3N4 can be considered as effective material for hydrogen storage alloy modification.

Achieving new insights on rational design and application of double perovskite Y2CrMnO6 nanostructures as potential materials for electrochemical hydrogen storage performance

Fossil fuel consumption and environmental concerns have long motivated the use of electric vehicles around the world. To meet the global energy demand, hydrogen has been proposed as a clean energy carrier with carbon-free combustion. There is, however, a great need for high-performance electrode materials in hydrogen storage applications in order to achieve the desired goals of long life and superior specific capacity. The purpose of our study is to investigate how novel double perovskite Y2CrMnO6 (YCMO) nanostructures can be used as highly active electrocatalysts in hydrogen storage activity by kinetics of redox and physisorption mechanisms. For the first time, spherical-shaped YCMO nanoparticles were fabricated via sol-gel auto-combustion using grape juice as fuel and complexing agent. A series of physic-chemical and electrochemical techniques was used to analyze the electrochemical performance of resultant YCMO samples based on their uniformity, size, and phase purity, including X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), Fourier-Transform Infrared Spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET), Cyclic Voltammetry (CV), chronopotentiometry, electrochemical impedance spectroscopy (EIS), and Tafel polarization. At a constant current of 1 mA in a three electrode set-up, the 15th profile of hydrogen storage capacity of YCMO-15, synthesized with 15 mL of grape juice, reached a maximum value of 465 mAh g−1 at a constant current of 1 mA, which is higher than that of YCMO-5 (355 mAh g−1) and YCMO-10 (350 mAh g−1). The results presented here can also lead to a new plan for developing Cr–Mn-based double perovskite oxides with hydrogen storage properties.

Hydrothermal architecture of Bi0.48Tb1.52Ti2O7/polyaniline nanocomposites to improve electrochemical hydrogen storage performance

Today, with the emergence of new technologies and the expansion of renewable energy infrastructure such as hydrogen, the discussion of energy security and the promotion of active materials for advanced hydrogen storage has an important place. For this purpose, in this research, an important strategy was designed to develop the electrochemical performance of electroactive materials Bi0.48Tb1.52Ti2O7 (BTTO) nanostructure was prepared through a hydrothermal route in the presence of fructose as a biotemplate agent. To achieve the desired chemical composition and to optimize the size and morphology, the reaction temperature was changed. The effect of polyaniline conductive polymer to improve hydrogen storage capacity was studied by introducing two composites. The structural characteristics, dimensions, and porosity of the products were investigated through Fourier transform infrared (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscope (FE-SEM), high-resolution transmission electron microscope (HR-TEM) and Brunauer-Emmett-Teller (BET). In the following, the potential of pristine Bi0.48Tb1.52Ti2O7 nanoparticles and Bi0.48Tb1.52Ti2O7/Polyaniline (BTTO/PANI) nanocomposites in the direction of hydrogen storage were evaluated through CV, EIS and CP techniques. BTTO/PANI nanocomposites showed a discharge capacity of 1223 mAhg−1 after 15 cycles. This study showed the potential effect of PANI in terms of improving conductivity and providing more charge transfer channels for hydrogen transfer.

Enhanced electrochemical hydrogen storage performance of Co9S8 material by doping with cobalt nanoparticles embedded hollow porous carbon nanofibers

Co-axial electrospinning has been regarded as an effective technology to fabricate hollow or core/shell nanofibers. Herein, co-axial electrospinning was carried out employing polymethyl methacrylate (PMMA) and polyacrylonitrile (PAN) as the core and shell components. Cobalt acetate was used as the cobalt source. The cobalt nanoparticles embedded hollow porous carbon fibers (Co/HCNF) were obtained after electrospinning and subsequent carbonization process. For comparison, the conventional carbon fibers (CNF), hollow carbon fibers (HCNF), and cobalt nanoparticles modified carbon fibers (Co/CNF) were also synthesized. Co9S8 material was manufactured via mechanical alloying. By adjusting the types of carbon fibers, a series of carbon fibers modified Co9S8 composites were obtained by ball milling and their electrochemical hydrogen storage properties were studied. As a result, the Co9S8 + Co/HCNF electrode showed the higher discharge capacity of 603.3 mAh/g than CNF, HCNF, Co/CNF modified Co9S8 and conventional Co9S8 electrodes. The Co nanoparticles within Co/HCNF provided high electrocatalytic activity. The special hollow porous structure and high specific surface area of Co/HCNF increased the conductivity, offered more electrochemical active sites and rapid channel for charge transfer. Moreover, Co9S8 + Co/HCNF also demonstrated improved high-rate dischargeability (HRD), capacity retention and kinetics properties. An advantageous solid-solid interface may be generated between Co9S8 and Co/HCNF, serving as a beneficial electron conduction path and facilitating the hydrogen diffusion, thereby enhancing the electrode performance of Co9S8 material.

Synthesis of MOF derived porous cobalt/N-doped carbon polyhedrons for enhancing the electrochemical hydrogen storage properties of Co–P material

Employing metal-organic framework ZIF-67 as the precursor, the porous cobalt/N-doped carbon polyhedron (Co–CN) was synthesized via a facile high temperature carbonization process. Co–P material was synthesized through mechanical alloying. By adjusting the content of Co–CN and milling time, a series of Co–P + Co–CN composite electrodes were prepared to enhance the electrochemical hydrogen storage performance of Co–P. Ultimately, the electrode of 5 wt% Co–CN modified Co–P milling for 5 min attained the best discharge capacity of 590.4 mAh/g. The special porous structure and high specific surface area (SSA) of Co–CN derived from ZIF-67 could provide more electrochemical active sites. The nitrogen-doped carbon could further improve the conductivity of Co–P. After Co–CN polyhedrons modification, the HRD, capacity retention and kinetics properties were also enhanced. The Co–CN porous framework can serve as the active additive for designing the high-performance hydrogen storage materials.

A study on electrochemical hydrogen storage performance of bituminous-derived mesoporous carbon/zinc oxide nanocomposite

A study on electrochemical hydrogen storage performance of bituminous-derived mesoporous carbon/zinc oxide nanocomposite

Enhanced electrochemical hydrogen storage performance of lanthanum zirconium oxide ceramic microstructures synthesized by a simple approach

Two rare-earth zirconate oxides RE2Zr2O7 (RE = La and Nd) with pyrochlore structures were fabricated, employing a simple and modified solid-state route. After confirmation of their microstructure, physicochemical features, and morphologies, the fabricated pyrochlores were applied for electrochemical hydrogen storage, and their capacity was compared in an alkaline medium. The La2Zr2O7 microstructure exhibited an enhanced electrochemical hydrogen storage performance (maximum discharge capacity = 2350 mAh/g) compared to the Nd2Zr2O7 structures. Having a higher specific surface, as well as a more favorable physical and chemical nature, could be responsible for this more suitable performance. Lanthanum zirconate ceramic microstructure could be introduced as an active material with an appropriate capacity for electrochemical hydrogen storage.

Effect of Nitrogen and Sulfur Co-Doped Graphene on the Electrochemical Hydrogen Storage Performance of Co0.9Cu0.1Si Alloy

Effect of Nitrogen and Sulfur Co-Doped Graphene on the Electrochemical Hydrogen Storage Performance of Co0.9Cu0.1Si Alloy

Enhanced hydrogen storage capacity of NiAl-layered double hydroxide modified with Tb3Fe5O12 nanostructures

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.

Evaluation of electrochemical hydrogen storage capability of graphene oxide multi-layer coating

Due to its unique physical and chemical properties, graphene oxide (GO) has excellent potential in energy-saving applications, especially in hydrogen storage materials such as bulk and layer coatings. A three-layer GO/Ni/GO coating was applied successfully on the Ni-foam through the hybrid coating process. GO was firstly synthesized by modified Hummers' method and then deposited on Ni-Foam using an electrophoretic deposition (EPD) method at 40, 60, and 80 V at various times (1 and 2 h). Furthermore, Ni-layer was applied on the first applied to GO layer using a Ni-electroplating bath at 3 V for 3 min. For evaluation of the electrochemical hydrogen storage performance, cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) were carried out in 1 M NaOH solution at room temperature. Obtained results showed a significant improvement in the amount of adsorbed hydrogen. The hydrogen storage capacity was increased from 88 to 741 F. g−1, and load transfer resistance decreased from 260 to 35 Ω for uncoated and coated porous substrates, respectively, which is due to the achieved high specific area. Based on the hydrogen storage capacity, the optimum EPD method is 60 V and 2 h.

Enhanced electrochemical hydrogen storage performance upon the Pt-Co nanoparticles decorated N-doped mesoporous carbon

Carbonaceous materials are proved to be the promising materials for storing hydrogen electrochemically. To enhance the performance, decorated Pt-Co bi-metallic nanoparticles onto the N-doped mesoporous carbon material were developed while Co enriched the capacity, and Pt was used to enhance the kinetic performance. Results showed that the hydrogen storage capacity of 2% Pt-Co@NMC material was over 360 mAh g−1 under a current density of 100 mA g−1, and the capacity retention was 53.6% under the 2000 mA g−1 rate over that at 100 mA g−1. Furthermore, it also carries low self-discharge and good cycling performance. First-principles calculations revealed that the adsorption of the H atom on the Pt (110) crystal plane is the most stable, which is mainly due to the hydrogen spillover effect to improve the kinetic performance of hydrogen intercalation.

Enhanced electrochemical hydrogen storage performance of titanate-based nanostructures synthesized by facile auto-combustion: Li2TiO3 nanostructures versus LaTiO3 nanoperovskites

Green energies are vital for near-future energy needs. Hydrogen is a promising secondary energy career that counted as a clean-burning fuel. However, hydrogen suffers from a low volumetric energy density at ambient temperature and pressure. This deficiency has been overcome by “solid-state hydrogen storage” technologies, where the hydrogen is adsorbed/absorbed - depending on the type of materials - on a solid surface. Mixed metal oxides (MMOs) particularly transition-based metal oxides have been recently developed for hydrogen adsorption with a superior affinity for hydrogen. Here, we demonstrated two nanosized-MMOs based on (mono-) perovskite structure, Li2TiO3, and LaTiO3. These two MMOs are successfully synthesized via the auto-combustion method in the presence of starch fuel. After confirmation of their structures and morphologies, the samples are used for electrochemical hydrogen storage in an alkaline medium. The average particle diameters of Li2TiO3 and LaTiO3 are calculated to be around 16.74 and 24.46 nm, respectively. The results indicate a higher discharge capacity of LaTiO3 nanoperovskites (1140 mAh/g) as compared to Li2TiO3 nanoparticles (680 mAh/g); as confirmed primarily by cyclic voltammetry (CV), with the theoretical hydrogen capacities of 4.1% and 2.4%, respectively. We believe that novel MMOs can be potentially fulfilled the requirements of future energy targets, arranged and reported by US-department of energy (DOE).

Preparation of carbon nanofiber supported Co nanoparticles for improving the electrochemical hydrogen storage properties of Co9S8 alloy

Co9S8 alloy was synthesized through mechanical ball milling, and cobalt/carbon nanofiber (Co/CNF) was prepared by the electrospinning process. The addition of Co and CNF increased the discharge capacity of Co9S8 to 563.4 mA/g. Furthermore, the composite electrode exhibited superior high-rate discharge capability, corrosion resistance, and other kinetic properties. CNF provides high conductivity and more reaction sites for Co nanoparticles. Co nanoparticles participate in redox reactions and show a catalytic effect. Moreover, the synergistic effect of CNF and Co also promotes the electrochemical hydrogen storage and kinetic performances of Co9S8 alloy.

Enhanced electrochemical hydrogen storage performance of Ti49Zr26Ni25 quasicrystal alloy by coating with ZIF-8 derived porous carbon/MoS2 composite

Ti 49 Zr 26 Ni 25 quasicrystal alloy is prepared via mechanical alloying and subsequent annealing. ZIF-8 derived porous carbon (ZIF-8-C) is obtained through thermal treatment of zinc-based MOF ZIF-8. The solvothermal method is used to fabricate the ZIF-8 derived carbon/MoS 2 (C/MoS 2 ) composite. Then, the C/MoS 2 hexahedral particles are coated on the Ti 49 Zr 26 Ni 25 surface by ball-milling. For comparison, the Ti 49 Zr 26 Ni 25 + ZIF-8-C and Ti 49 Zr 26 Ni 25 + MoS 2 composites are also prepared. The C/MoS 2 modified Ti 49 Zr 26 Ni 25 displays higher hydrogen storage capacity of 279.1 mAh/g than separate ZIF-8-C or MoS 2 coated alloy and original Ti 49 Zr 26 Ni 25 . The superior properties may be due to the synergistic effect between high conductive flexible ZIF-8-C porous carbon and active MoS 2 . The preferable oxidation/corrosion resistance and cyclic stability are also realized. Moreover, Ti 49 Zr 26 Ni 25 + C/MoS 2 electrode exhibits higher exchange current density I 0 , limiting current density I L , hydrogen diffusion coefficient D and lower charge-transfer resistance R ct . The distinctive structural feature of C/MoS 2 can serve a rapid passageway and accelerate the hydrogen diffusion, thus further improving the kinetic properties and electrochemical activity of Ti 49 Zr 26 Ni 25 alloy electrode. • A facile solvothermal method is used to prepare ZIF-8 derived carbon/MoS 2 composite. • Ti 49 Zr 26 Ni 25 quasicrystal alloy coated with C/MoS 2 is obtained via ball milling. • The hydrogen storage capacity, HRD and kinetics performance of electrodes are improved. • The synergistic effect of MoS 2 and ZIF-8-C is advantageous to the hydrogen diffusion.

Influence of structural and chemical environmental factors on electrochemical hydrogen storage in carbon materials

The influences of pore size, specific surface area, and surface chemistry of carbon material as well as the pH value of electrolyte solution on the electrochemical hydrogen storage performances are investigated. Three types of carbon materials carrying micro-, meso- and macro- pores, respectively, were either commercial available or synthesized through the hard template method. Their electrochemical hydrogen storage behaviors are studied in acidic, neutral, and alkaline solutions. The results indicate that microporous carbon with a high specific surface area has great advantages in hydrogen storage capacity, stability, and cycle performance. Moreover, nitrogen-doped porous carbon can not only improve hydrogen storage capacity but also both rate and hydrogen storage stability. The neutral electrolyte provides a larger voltage window while the alkaline media exhibits positive impacts on the hydrogen storage capacity. At the same time, regardless of the pH value of the electrolytes, the larger the specific surface area of the carbon material, the higher the hydrogen storage capacity.

Sonochemical synthesized BaMoO4/ZnO nanocomposites as electrode materials: A comparative study on GO and GQD employed in hydrogen storage

Due to poor rate proficiency and electrochemical capacity of transition metal oxides, production electrode materials as operative way to develop the electrochemical performance is a crucial strategy to make sure the great electroactive sites and fast electron/ion diffusion route. In order to solve this problem, carbon-based nanocomposites as conductive substrates are applied. The nanostructured BaMoO4/ZnO was produced by sonochemical method in the presence of tween 20 as stabilizing agent. Effect of graphene quantum dots (GQDs) and graphene oxide (GO) for developing hydrogen capacity of BaMoO4/ZnO was studied by providing representative composites of BaMoO4/ZnO-GQDs and BaMoO4/ZnO-GO. For this purpose, GQDs was synthesized using green source of Spiraea crenata and the GO provided by commercial company. The structural analysis shows preparation of scales-like morphology of BaMoO4/ZnO without any impurities through SEM, TEM, XRD, EDS and FT-IR characterization data. Also, the specific surface area for BaMoO4/ZnO-GQDs (11 m2/g) and BaMoO4/ZnO-GO (124 m2/g) nanocomposites increased by comparing to BaMoO4/ZnO (9.1 m2/g). The resultant nanocomposites used as new active compounds for applying in hydrogen storage strategies using cyclic voltammetry and chronopotentiometry tests. Comprehensively, the hydrogen capacitance after 15 cycles was demonstrated on the nanostructured BaMoO4/ZnO about 129 mAhg−1. It demanded the maximum capacitance for BaMoO4/ZnO-GQDs and BaMoO4/ZnO-GO nanocomposites were 284 and 213 mAhg−1 respectively, which was higher than the initial nanostructured BaMoO4/ZnO. It was exposed from the carbon based structured that; the endorsed electrochemical hydrogen storage (EHS) performance is ascribed to the reaction of the redox pair of Mo6+ /Mo5+ at the active sites throughout the EHS procedure. This study delivers a novel plan and potential sorption electrode materials to progress the intrinsic action of conductive compounds.

Insights into impacts of Co3O4-CeO2 nanocomposites on the electrochemical hydrogen storage performance of g-C3N4: Pechini preparation, structural design and comparative study

The present work reports one-pot modified Pechini synthesis of porous Co3O4-CeO2 (CC) nanostructures with the templating environment of succinic acid, and further it is decorated with graphitic carbon nitride (g-C3N4 or CN) substrate. Interfacial architecture of the multicomponent nanocomposites can promote the synergistic effect by adjusting the weight percent of CC guest (30%, 50% and 70%) into CN host. The consequent changes in the compositional, morphological features and porosity of the resulting composites are unraveled by a combination of XRD, Raman, FE-SEM, HR-TEM, and BET analyses. Remarkably, the redox reactivity and considerable electronic conductivity of nanostructured electrode materials ascertains by cyclic voltammetry (CV) and chronopotentiometry charge–discharge (CCD) techniques in 2.0 M KOH medium. Fabricated Co3O4–CeO2/g-C3N4 (CC-CNx%) nanocomposites proved as the energetic electrode materials for realizing hydrogen storage performance at current of 1 mA. It is demonstrated that the CC/Cu platforms can produce the discharge efficiency of 619.25 mAhg−1 after 15 cycles. However, among the various adding, the ternary nanocomposites with 50.0 wt% CC nanoparticles achieved the higher discharge capacity of about 1020.53 mAhg−1 in three electrode cell. The coupling effect of interfacial architecture presented here suggests alternative insights into constructing uniformly nanocomposites for highly efficient energy storage applications.

Phosphonic acid-functionalized carbon nanotubes/bismuth sulfide composite with efficient electrochemical hydrogen storage performance

In this work, phosphonic acid-functionalized carbon nanotubes/bismuth sulfide composite (PAFCN/BS) has been produced successfully by a facile solution reaction method, and it has been characterized by transmission electron microscope (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), Fourier Transform infrared spectroscopy (FT-IR) and X-ray powder diffraction (XRD). Because of the efficient synergistic effect of phosphonic acid functionalized-carbon nanotubes and bismuth sulfide, the composite displays excellent electrochemical hydrogen storage and stability performances. Furthermore, the as-synthesized composite exhibits very low charge transfer resistance which signifies fast electron transfer. Based on the facile synthesis of the composite and its excellent performance of electrochemical hydrogen storage, PAFCN/BS can stand out as a promising efficient electrode material in the field of electrochemical hydrogen storage.

Enhanced electrochemical hydrogen storage performance of organophosphonic carboxylic acid-modified multiwalled carbon nanotubes/Bi2S3 composite

Hydrogen energy, one of the recognized green energy sources, has many advantages, and electrochemical hydrogen storage has been regarded as one of the outstanding energy storage systems. The present research describes that the organophosphonic carboxylic acid-modified multiwalled carbon nanotubes/Bi2S3 composite (OPCAMCN/BS) has been produced successfully by a facile solution reaction method, and it has been characterized by Fourier transform infrared (FTIR), scanning electron microscope (SEM), energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), and porous structure analysis. Because of the efficient synergistic effect of organophosphonic carboxylic acid-functionalized multiwalled carbon nanotubes and bismuth sulfide, the composite displays excellent electrochemical hydrogen storage and stability performances. The electrochemical hydrogen storage performance of the OPCAMCN/BS electrodes has been measured, and its discharge capacity (950.9 mAh/g) greatly exceeds the relevant values of those two reference materials, and the cycle life of the OPCAMCN/BS electrodes is higher than that of Bi2S3 and MWCNTs/BS. Furthermore, the as-synthesized composite OPCAMCN/BS exhibits very low charge transfer resistance which signifies fast electron transfer. Therefore, OPCAMCN/BS is expected to be used as a kind of excellent electrochemical hydrogen storage material and can be applied in the areas of renewable energy to reduce the use of fossil fuels.