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Permanent implants made from titanium are widely used and successfully implemented in medicine to address problems related to orthopedic and oral disorders. However, implants that interact in all cases optimally and durably with bone tissue have yet to be developed. Here, the authors suggest a phospholipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-ethanolamine (POPE) lipid coating to partially mimic the biological cell membrane. To improve the homogeneity of the POPE distribution on the metal surface, the lipids are applied by spray coating. It is shown that the spray coating leads to two types of multilamellar POPE structures. Our experimental results demonstrate that these coatings are stable in a liquid environment in the range of physiological temperatures due to the unique interbilayer interaction of POPE lipids. Additionally, the interaction of the POPE multilayer structure with human serum albumin is considered. A simultaneous analysis of the specular and off-specular data provides structural information necessary to assess the quality of the coating for future applications. [ABSTRACT FROM AUTHOR]

To improve nanoconfinement of LiBH 4 and MgH 2 in carbon aerogel scaffold (CAS), particle size reduction of MgH 2 by premilling technique before melt infiltration is proposed. MgH 2 is premilled for 5 h prior to milling with LiBH 4 and nanoconfinement in CAS to obtained nanoconfined 2LiBH 4 –premilled MgH 2 . Significant confinement of both LiBH 4 and MgH 2 in CAS, confirmed by SEM–EDS–mapping results, is achieved due to MgH 2 premilling. Due to effective nanoconfinement, enhancement of CAS:hydride composite weight ratio to 1:1, resulting in increase of hydrogen storage capacity, is possible. Nanoconfined 2LiBH 4 –premilled MgH 2 reveals a single–step dehydrogenation at 345 °C with no B 2 H 6 release, while dehydrogenation of nanoconfined sample without MgH 2 premilling performs in multiple steps at elevated temperatures (up to 430 °C) together with considerable amount of B 2 H 6 release. Activation energy ( E A ) for the main dehydrogenation of nanoconfined 2LiBH 4 –premilled MgH 2 is considerably lower than those of LiBH 4 and MgH 2 of bulk 2LiBH 4 –MgH 2 (Δ E A = 31.9 and 55.8 kJ/mol with respect to LiBH 4 and MgH 2 , respectively). Approximately twice faster dehydrogenation rate are accomplished after MgH 2 premilling. Three hydrogen release ( T = 320 °C, P (H 2 ) = 3–4 bar) and uptake ( T = 320–325 °C, P (H 2 ) = 84 bar) cycles of nanoconfined 2LiBH 4 –premilled MgH 2 reveal up to 4.96 wt. % H 2 (10 wt. % H 2 with respect to hydride composite content), while the 1st desorption of nanoconfined sample without MgH 2 premilling gives 4.30 wt. % of combined B 2 H 6 and H 2 gases. It should be remarked that not only kinetic improvement and B 2 H 6 suppression are obtained by MgH 2 premilling, but also the lowest dehydrogenation temperature ( T = 320 °C) among other modified 2LiBH 4 –MgH 2 systems is acquired. [ABSTRACT FROM AUTHOR]

Destabilization of LiBH4 by nanoconfinement in poly (methyl methacrylate)–co–butyl methacrylate (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 ∼80 °C (ΔT = 340 and 170 °C as compared with milled LiBH4 and nanoconfined LiBH4 in carbon aerogel, respectively). At 120 °C under vacuum, nano LiBH4–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, nano LiBH4–PMMA–co–BM can be rehydrogenated at the mildest condition (140 °C under 50 bar H2 for 12 h) among other modified LiBH4 reported in the previous literature. Due to the hydrophobicity of PMMA–co–BM host, deterioration of LiBH4 by oxygen and humidity in ambient condition is avoided after nanoconfinement. Although the interaction between LiBH4 and the pendant group of PMMA–co–BM leads to a reduced hydrogen storage capacity, significant destabilization of LiBH4 is accomplished. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]