Nanoconfined 2LiBH4eMgH2eTiCl3 in carbon aerogel scaffold for reversible hydrogen storage

Nanoconfinement of 2LiBH4–MgH2–TiCl3 in resorcinol–formaldehyde carbon aerogel scaffold (RF–CAS) for reversible hydrogen storage applications is proposed. RF–CAS is encapsulated with approximately 1.6 wt. % TiCl3 by solution impregnation technique, and it is further nanoconfined with bulk 2LiBH4–MgH2 via melt infiltration. Faster dehydrogenation kinetics is obtained after TiCl3 impregnation, for example, nanoconfined 2LiBH4–MgH2–TiCl3 requires ∼1 and 4.5 h, respectively, to release 95% of the total hydrogen content during the 1st and 2nd cycles, while nanoconfined 2LiBH4–MgH2 (∼2.5 and 7 h, respectively) and bulk material (∼23 and 22 h, respectively) take considerably longer. Moreover, 95–98.6% of the theoretical H2 storage capacity (3.6–3.75 wt. % H2) is reproduced after four hydrogen release and uptake cycles of the nanoconfined 2LiBH4–MgH2–TiCl3. The reversibility of this hydrogen storage material is confirmed by the formation of LiBH4 and MgH2 after rehydrogenation using FTIR and SR-PXD techniques, respectively.Fil: Gosalawit Utke, Rapee. Helmholtz-Zentrum Geesthacht; Alemania. Suranaree University of Technology; TailandiaFil: Milanese, Chiara. Università degli studi di Pavia; ItaliaFil: Javadian, Payam. University Aarhus; DinamarcaFil: Jepsen, Julian. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Laipple, Daniel. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Karmi, Fahim. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz-Zentrum Geesthacht; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jensen, Torben R.. University Aarhus; DinamarcaFil: Marini, Amedeo. Università degli studi di Pavia; ItaliaFil: Klassen, Thomas. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Dornheim, Martin. Helmholtz-Zentrum Geesthacht; Alemani

Hydrogen sorption in the LiH-LiF-MgB2 system

A composite material in the LiH-LiF-MgB2 system has been synthesized by high-energy ball milling. Some peaks in addition to that of the binary 2LiH-MgB2 and 2LiF-MgB2 systems are observed for the composite material by high-pressure differential scanning calorimetry (HP-DSC), indicating the formation of intermediate phases. In situ synchrotron radiation powder X-ray diffraction (SR-PXD) performed at 60 bar of H-2 and 390 degrees C shows a superposition of both reaction pathways that are typical for 2LiH-MgB2 and 2LiF-MgB2. After hydrogen absorption of the LiH-LiF-MgB2 composite the vibrational modes of LiBH4 were observed by attenuated total reflection infrared (ATR-IR) spectroscopy. The F-19 MAS NMR spectrum of the LiF-LiBH4 sample after heat treatment in hydrogen is strongly dominated by the centerband and spinning sidebands from LiF; in addition, a low-intensity resonance, very similar to that of [BF4](-) ion, is identified

Sorption behavior of the MgH2-Mg2FeH6 hydride storage system synthesized by mechanical milling followed by sintering

The hydrogen sorption behavior of the Mg2FeH6eMgH2hydride system is investigated via in-situ synchrotron and laboratory powder X-ray diffraction (SR-PXD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), particle size distribution (PSD) and volumetric techniques. The Mg2FeH6eMgH2 hydride system is obtained by mechanical milling in argon atmosphere followed by sintering at high temperature and hydrogen pressure. In-situ SR-PXD results show that upon hydriding MgH2 is a precursor for Mg2FeH6 formation and remained as hydrided phase in the obtained material. Diffusion constraints preclude the further formation of Mg2FeH6. Upon dehydriding, our results suggest that MgH2 and Mg2FeH6 decompose independently in a narrow temperature range between 275 and 300 C. Moreover, the decomposition behavior of both hydrides in the Mg2FeH6eMgH2 hydride mixture is influenced by each other via dual synergetic-destabilizing effects. The final hydriding/dehydriding products and therefore the kinetic behavior of the Mg2FeH6eMgH2 hydride system exhibits a strong dependence on the temperature and pressure conditions.Fil: Puszkiel, Julián Atilio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Gennari, Fabiana Cristina. Comision Nacional de Energia Atomica. Gerencia de Area de Aplicaciones de la Tecnologia Nuclear. Gerencia de Investigacion Aplicada; . Universidad Nacional de Cuyo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arneodo Larochette, Pierre Paul. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comision Nacional de Energia Atomica. Gerencia de Area de Aplicaciones de la Tecnologia Nuclear. Gerencia de Investigacion Aplicada; . Universidad Nacional de Cuyo; ArgentinaFil: Karimi, Fahim. Materials Technology. Institute of Materials Research; AlemaniaFil: Pistidda, Claudio. Materials Technology. Institute of Materials Research; AlemaniaFil: Gosalawit Utke, Rapee. Materials Technology. Institute of Materials Research; Alemania. Suranaree University of Technology. Institute of Science, School of Chemistry; TailandiaFil: Jepsen, Julian. Materials Technology. Institute of Materials Research; AlemaniaFil: Jensen, Torben R.. University of Aarhu. Center for Energy Materials, iNANO and Department of Chemistry; DinamarcaFil: Gundlach, Carsten. Lund University. MAX-lab; SuizaFil: Bellosta von Colbe, José. Materials Technology. Institute of Materials Research; AlemaniaFil: Klassen, Thomas. Materials Technology. Institute of Materials Research; AlemaniaFil: Dornheim, Martin. Materials Technology. Institute of Materials Research; Alemani

Hydrogen Storage Materials for Mobile and Stationary Applications: Current State of the Art

One of the limitations to the widespread use of hydrogen as an energy carrier is its storage in a safe and compact form. Herein, recent developments in effective high-capacity hydrogen storage materials are reviewed, with a special emphasis on light compounds, including those based on organic porous structures, boron, nitrogen, and aluminum. These elements and their related compounds hold the promise of high, reversible, and practical hydrogen storage capacity for mobile applications, including vehicles and portable power equipment, but also for the large scale and distributed storage of energy for stationary applications. Current understanding of the fundamental principles that govern the interaction of hydrogen with these light compounds is summarized, as well as basic strategies to meet practical targets of hydrogen uptake and release. The limitation of these strategies and current understanding is also discussed and new directions proposed

Novel synthesis of porous Mg scaffold as a reactive containment vessel for LiBH4

A novel porous Mg scaffold was synthesised and melt-infiltrated with LiBH 4 to simultaneously act as both a confining framework and a destabilising agent for H 2 release from LiBH 4 . This porous Mg scaffold was synthesised by sintering a pellet of NaMgH 3 at 450 °C under dynamic vacuum. During the sintering process the multi-metal hydride, decomposed to Mg metal and molten Na. The vacuum applied in combination with the applied sintering temperature, created the ideal conditions for the Na to vaporise and to gradually exit the pellet. The pores of the scaffold were created by the removal of the H 2 and Na from the body of the NaMgH 3 pellet. The specific surface area of the porous Mg scaffold was determined by the Brunauer-Emmett-Teller (BET) method and from Small-Angle X-ray Scattering (SAXS) measurements, which was 26(1) and 39(5) m 2 g -1 respectively. The pore size distribution was analysed using the Barrett-Joyner-Halenda (BJH) method which revealed that the majority of the pores were macropores, with only a small amount of mesopores present in the scaffol d. The melt-infiltrated LiBH 4 was highly dispersed in the porous scaffold according to the morphological observation carried out by a Scanning Electron Microscope (SEM) and also catalysed the formation of MgH 2 as seen from the X-ray diffraction (XRD) patterns of the samples after the infiltration process. Temperature Programmed Desorption (TPD) experiments, which were conducted under various H 2 backpressures, revealed that the melt-infiltrated LiBH 4 samples exhibited a H 2 desorption onset temperature (T des ) at 100 °C which is 250 °C lower than the bulk LiBH 4 and 330 °C lower than the bulk 2LiBH 4 /MgH 2 composite. Moreover, the LiH formed during the decomposition of the LiBH 4 was itself observed to fully decompose at 550 °C. The as-synthesised porous Mg scaffold acted as a reactive containment vessel for LiBH 4 which not only confined the complex metal hydride but also destabilised it by significantly reducing the H 2 desorption temperature down to 100 °C

Nanoconfined 2LiBH4 - MgH2 in nanoporous carbon aerogel scaffolds for reversible hydrogen storage

Nanoconfined 2 LiBH4 - MgH2 is prepared with and without catalyst (TiCl3) by direct melt infiltration of bulk 2 LiBH4 - MgH2 into an inert carbon aerogel scaffold material. Homogeneous dispersion of MgH2, LiBH4 and TiCl3 in the nanoporous structure of carbon scaffold is assured by several means, such as SEM-EDS via focus ion beam technique, in situ synchrotron radiation powder X-Ray diffraction, and N2 adsorption-desorption. The nanoconfined 2LiBH4-MgH2 system with and without catalyst release 100% hydrogen storage capacity within 100 and 200 min respectively, while the time for the bulk material is 30 h. A reversible 10.8 wt % H2 with respect to the metal hydride content over 4 hydrogen release and uptake cycles is preserved from both the nanoconfined systems

Nanoconfined 2LiBH(4)-MgH2 Prepared by Direct Melt Infiltration into Nanoporous Materials

Nanoconfined 2LiBH(4)-MgH2 is prepared by direct melt infiltration of bulk 2LiBH(4)-MgH2 into an inert nanoporous resorcinol-formaldehyde carbon aerogel scaffold material. Scanning electron microscopy (SEM) micrographs and energy dispersive X-ray spectroscopy (EDS) mapping reveal homogeneous dispersion of Mg (from MgH2) and B (from LiBH4) inside the carbon aerogel scaffold. Moreover, nanoconfinement of LiBH4 in the carbon aerogel scaffold is confirmed by differential scanning calorimetry (DSC). The hydrogen desorption kinetics of the nanoconfined 2LiBH(4)-MgH2 is significantly improved as compared to bulk 2LiBH(4)-MgH2. For instance, the nanoconfined 2LiBH(4)-MgH2 releases 90% of the total hydrogen storage capacity within 90 mm, whereas the bulk material releases only 34% (at T = 425 degrees C and p(H-2) = 3.4 bar). A reversible gravimetric hydrogen storage capacity of 10.8 wt % H-2, calculated with respect to the metal hydride content, is preserved over four hydrogen release and uptake cycles

Destabilization of LiBH4 by Nanoconfinement in PMMA–co–BM Polymer Matrix for Reversible Hydrogen Storage

Destabilization of LiBH4 by nanoconfinement in poly (methyl methacrylate)-co-butyl meth-acrylate (PMMA-co-BM), denoted as nano LiBH4-PMMA-co-BM, is proposed for reversible hydrogen storage. The onset dehydrogenation temperature of nano LiBH4-PMMA-co-BM is reduced to 80C (DeltaT=340 and170 °C as compared with milled LiBH4 and nanoconfined LiBH4 in carbon aerogel,respectively).At120°C under vacuum,nanoLiBH4-PMMA-co-BM releases 8.8 wt.% H2 with respect to LiBH4 content within 4 h during the 1st dehydrogenation, while milled LiBH4 performs no dehydrogenation at the same temperature and pressure condition. Moreover,nanoLiBH4-PMMA-coBM can be rehydrogenated at the mildest condition(140°C under50 barH2 for12h) among other modifiedLiBH4 reportedinthepreviousliterature