HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS最新文献

{"title":"Mg-based composites as effective materials for storage and generation of hydrogen for FC applications","authors":"D. Korablev, A. Bezdorozhev, V. Yartys, J. Solonin","doi":"10.15407/materials2021.053","DOIUrl":"https://doi.org/10.15407/materials2021.053","url":null,"abstract":"Today, hydrogen is considered as an ideal choice for storing and carrying energy produced by renewable power sources since it is renewable, eco-friendly and has a high energy density. However, due to the low hydrogen storage capacity, high cost and safety issues of the conventional storage methods, several challenges need to be resolved to effectively use hydrogen in mobile applications. Solid-state hydrogen storage in atomic form in hydrides is a promising method of storage for this purpose, particularly because a double amount of hydrogen can be produced via hydrolysis reaction of chemically active hydrides. Among the metal hydrides, magnesium hydride (MgH2) is considered to be one of the most attractive candidates. However, the hydrolysis reaction is rapidly hindered by the passivation layer formed on the surface of MgH2. In order to improve MgH2 hydrolysis efficiency various approaches have been applied. This paper reviews recent progress on the modifications of MgH2-based materials by adding different type of additives, including metals, oxides, hydroxides, halides and surfactants. The introduced additives possess different catalytic properties due to their intrinsic physical and chemical characteristics, and therefore can strongly influence the hydrolysis reaction of MgH2. The most promising results were obtained for various salt additives showing that the reaction rate depends mostly on the additive type rather than on concentration. The effect of preparation technique on the hydrolysis of MgH2 – MgCl2 composites was studied in detail. The obtained results indicate that efficient hydrolysis performance can be achieved by ball milling of the freshly synthesized MgH2 with 5 wt.% MgCl2 and 1 wt.% TiC–2TiB2 additives. The combination of the applied approaches exhibited a notable synergistic effect on the hydrogen generation.","PeriodicalId":367009,"journal":{"name":"HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115071594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogen generation by hydrolysis of metals and hydrides for portable energy supply","authors":"A. Kutsyi, A. Kytsya, V. Yartys, I. Zavaliy, Yuriy Pirskyy, J. Solonin, V. Berezovets, F. Manilevich, Yu. V. Verbovytskyy","doi":"10.15407/materials2021.015","DOIUrl":"https://doi.org/10.15407/materials2021.015","url":null,"abstract":"NATO project G 5233 “Portable energy supply” was executed by 4 teams (Institute for Energy Technology, Norway and 3 Institutes of the National Academy of Sciences of Ukraine). G5233 Project was focused on the development of hydrogen fueled portable energy supply systems integrating hydrogen generation and storage units based on use of light metals, metal and complex hydride materials and portable fuel cells. The weight efficient energy supply device was developed by using these selected materials and performance-optimised NaBH4 complex hydride. Besides, various new relevant units of equipment for the samples preparation and characterization were ordered and accommodated in the participants labs and the program of training of young scientists at IFE, Norway was accomplished. Different types of materials for hydrogen generation were synthesized and characterized (activated aluminium alloys, Mg-Al alloys, MgH2 and their composites, NaBH4 with catalytic additives). The challenging objective of reaching a completeness of the hydrolysis of MgH2 was achieved; the reaction conditions were optimized and the particular focus applications integrating efficient hydrogen generation systems were identified. The mechanism and the kinetics model of the hydrolysis process of MgH2 in water solutions have been proposed which successfully describe the experimental data. In parallel with the hydrolysis reaction resulting in hydrogen generation and formation of Mg(OH)2 , the process involves passivation of the MgH2 surface by the formed Mg(OH)2 precipitate followed by its re-passivation with the rate constants of these processes being established. Increase of the concentration of MgCl2 leads to just a minor increase in the rate constant of the interaction of MgH2 with water but leads to a sharp increase of the rate constant of the repassivation of MgH2 surface. To achieve efficient hydrolysis of NaBH4 , different types of catalysts (heterogeneous on the basis of Pt and \"homogeneous\" - salts of Ni+2 and Co+2) were studied and optimized. Several systems were selected as candidates to provide the required hydrogen flow to operate a 30 W fuel cell over a given time exceeding 1 hour, based on a use of inexpensive and affordable hydrogen-containing materials and catalytic additives. 3 individual hydrolysis workstations (1 in Norway and 2 in Ukraine) were built, tested and optimized. The plan of the work to reach the objectives of the Project G5233 “Portable energy supply” is completely accomplished, all the milestones are successfully fulfilled and the overall goal of the Project is reached.","PeriodicalId":367009,"journal":{"name":"HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129393655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ni-, Co- and Pt-based nanocatalysts for hydrogen generation via hydrolysis of NaBH4","authors":"V. Yartys, I. Zavaliy, A. Kytsya, V. Berezovets, Yuriy Pirskyy, F. Manilevich, Yu. V. Verbovytskyy, P. Lyutyy","doi":"10.15407/materials2021.094","DOIUrl":"https://doi.org/10.15407/materials2021.094","url":null,"abstract":"Ni-, Co- and Pt-based nanostructures were prepared via different physical-chemical methods and tested as the catalysts of hydrolysis of NaBH4. Ni-Co bimetallic nanoparticles with different Ni-Co ratios were synthesized by the modified polyol method via the reduction of in situ precipitated slurries of Ni and Co hydroxides by hydrazine in ethylene glycol solutions. It was found that a Ni- Co nanoparticles with the equal Ni/Co content and mean size of 130 nm are a more active catalyst as compared to Ni75Co25 and Ni25Co75 nanopowders and provide a constant rate of hydrogen evolution up to the full conversion of NaBH4. Zeolite supported Ni- and Co-based nanostructures (Ni-Z and Co-Z) as a convenient in use alternative to the metallic nanoparticles were synthesized via two-stage procedure consisted of adsorption of Ni2+ or Co2+ ions by zeolite from the aqueous solutions followed by the reduction of the adsorbed cations by NaBH4. Using SEM and EDX it was found that such method of synthesis provide the uniform distribution of 50 – 100 nm metallic nanopaticles both on the surface and in the bulk of the carrier due to the high cation-exchange capacity of the aluminosilicates. It was found that Co-Z catalyst is more active compared to Ni-Z and in studied conditions provides the H2 evolution rate close to 1450 mL/min per 1 g of precipitated metal. Various Pt-based nanocomposites were obtained by polyol synthesis and subsequently deposited on the carriers (carbon cloth or cordierite) as well as via a platinum electrodeposition on the titanium crump. It was found that the most efficient catalyst of the hydrolysis of NaBH4 is a cordierite-supported nanodispersed Pt which is able to maintain operation of a 30 W battery of fuel cells for 9-10 hours when using for the hydrolysis 1.1 L of 10 % NaBH4 solution.","PeriodicalId":367009,"journal":{"name":"HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129718311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activated aluminum for hydrogen generation from water","authors":"F. Manilevich, Yuriy Pirskyy, A. Kutsyi, V. Berezovets, V. Yartys","doi":"10.15407/materials2021.081","DOIUrl":"https://doi.org/10.15407/materials2021.081","url":null,"abstract":"Al-based alloys and mechanochemically activated aluminum powders were prepared in this study, and the regularities of their hydrolysis reaction with water were studied. Aluminum alloys were prepared by melting aluminum with additions of Ga–In–Sn eutectic (5 wt.%), bismuth (3 wt.%), antimony (3 wt.%), or zinc (3 wt.%). The temperature-dependent kinetics of their hydrolysis in a temperature range 25–70 °C was studied by using a volumetric technique. The most efficient activation of the hydrolysis process was achieved for the Al–Ga– In–Sn-Zn alloy, particularly at low temperatures (5 and 25° C). The addition of bismuth to the Al–Ga–In–Sn alloy significantly decreases the hydrolysis rate, whereas the addition of antimony has only a weak effect on the process, despite the fact that the standard electrode potentials of bismuth and antimony have rather close values. Commercially available aluminum PA-4 and ASD-1 powders were mechanochemically activated by Ga–In–Sn or Ga–In–Sn–Zn eutectic alloys (5 wt.%) and graphite (1–3 wt.%) in a mixer type ball mill. Subsequently, they were pressed (P = 4 MPa) into the pellets, which were used to generate hydrogen from water via the hydrolysis process. X-ray diffraction study of the milled PA-4 powder revealed the presence of four phases, including aluminum, graphite, and two In–Sn intermetallic compounds (In3Sn and In1–xSnx, were x ≈ 0.04). The quantitative analysis by EDX showed a uniform distribution of the activating additives over the pellet surface, while the graphite was partly aggregated. Studies on the hydrolysis kinetics when utilizing Al-based pellets demonstrated that the process readily proceeds at temperatures ≥ 5° C. At the same time, the efficiency of hydrogen generation depends on the amount of the added graphite, particle size of aluminum powders, duration and medium of their mechanochemical treatment, and the hydrolysis temperature.","PeriodicalId":367009,"journal":{"name":"HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126515117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrolysis of MgH2 in MgCl2 solutions as an effective way for hydrogen generation","authors":"V. Berezovets, A. Kytsya, Yu. V. Verbovytskyy, I. Zavaliy, V. Yartys","doi":"10.15407/materials2021.038","DOIUrl":"https://doi.org/10.15407/materials2021.038","url":null,"abstract":"Magnesium hydride (MgH2) has a high hydrogen storage capacity (7.6 wt%) and the Mg element is abundant on the earth. Due to its strong reduction ability, even at room temperature it can provide the hydrogen yield reaching 15.2 wt% H (1703 mL/g) when interacting with water, which makes it very attractive for the application in supplying hydrogen for autonomous H energy systems. However, the hydrolysis reaction is rapidly inhibited by the Mg(OH)2 passivation layer formed on the surface of MgH2. In order to remove the passivation film and improve the efficiency of the MgH2 hydrolysis process, several methods including alloying, ball milling, changing the aqueous solution, have been successfully utilized. In this paper the process of hydrolysis of magnesium hydride in aqueous solutions of MgCl2 used as a promotor of the interaction has been studied in detail. It was found that the initial hydrolysis rate, pH of the reaction mixture, and overall reaction yield are all linearly dependent of the logarithm of MgCl2 concentration. It has been shown that pH of the reaction mixture in the presence of MgCl2 is well described by considering a system “weak base and its salt with strong acid” type buffer solution. Reference data for this hydrolysis reaction were also carefully analyzed. The mechanism and the kinetic model of the process of MgH2 hydrolysis in water solutions involved passivation of the MgH2 surface by the formed Mg(OH)2 precipitate followed by its repassivation have been proposed. The obtained after the hydrolysis reactions precipitates were studied using XRD and EDS. It was found also that the final products of reaction consist of Mg(OH)2 (brucsite type) and remaining MgH2. This fact shows that the formation of solid species such as MgCl2 xMgO yH2O at the studied conditions is unlikely and decreasing of pH the reaction mixture has a different nature.","PeriodicalId":367009,"journal":{"name":"HYDROGEN BASED ENERGY STORAGE: STATUS AND RECENT DEVELOPMENTS","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116450137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}