Improving hydrogen storage in modified carbon materials

Jiménez, Vicente; Ramírez-Lucas, Ana; Sánchez, Paula; Valverde, J.L.; Romero, Amaya

doi:10.1016/j.ijhydene.2011.11.106

Cited by 43 publications

(32 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, CNFs, cylindrical graphitic nanostructures in which the graphene layers are aligned at an angle to the fiber axis, show highly ordered graphene sheets and consequently exhibit high electrical conductivity and chemical stability . In general, the functionalization process involves a reduction of the surface area and the micropore and mesopore volume due to partial pore blockage, which is related to the formation of functionalized oxygen groups . Compared with other carbonaceous materials, Carbon Vulcan XC‐72 presents a lower pore size and thus contains micropores where Pd nanoparticles can sink, reducing the number of active sites in the catalytic structure .…”

Section: Resultsmentioning

confidence: 84%

“…Palladium‐based anodic catalysts, denoted as Pd/X (where X refers to the different carbonaceous supports), were synthetized according to the sodium borohydride (NaBH 4 ) reduction method . Firstly 1600 mg of the selected support (functionalized low‐surface nanofibers (CNF f‐LS) or graphene flakes (GF), which were synthetized in our laboratory, or non‐functionalized low‐density nanofibers (CNF LS), commercially supplied by (Graphenano SL, Murcia, Spain) was dissolved in 200 mL of deionized water and stirred for 6 h. Then a PdN 2 O 7 · x H 2 O (1102.53 mg in 22.05 mL of deionized water) solution was added to the support‐suspended solution and kept under vigorous stirring for 12 h. The solvent was subsequently evaporated from the slurry sample on a Rotavapor R‐210 (Buchi, Flawil, Switzerland) at 60 °C. The resulting product was dried in an oven (Nabertherm) at 80 °C for 12 h. Finally a 0.2 mol L −1 solution of NaBH 4 was added dropwise to the solid sample (NaBH 4 /precursor molar ratio of 10) to reduce the metal ions to the active phase.…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Optimization of the catalytic support and membrane for the electrochemical reforming of ethanol in alkaline media

Calcerrada

Osa

Romero

et al. 2019

J of Chemical Tech & Biotech

Self Cite

View full text Add to dashboard Cite

BACKGROUND: In this work, the influence of the anodic catalyst carbonaceous support and the membrane on the electrochemical reforming of ethanol for hydrogen production in alkaline media has been studied. Physicochemical characterization and electrochemical activity measurements were performed for different palladium-based anodic catalysts. The best anodic catalyst was scaled up to two different membrane electrode assemblies (MEAs) based on anion exchange membranes (AEMs): Tokuyama and KOH-doped polybenzimidazole (PBI) membranes. In both systems, the influence of the temperature and the stability were evaluated for the electrochemical reforming of ethanol. RESULTS: Among the different investigated catalysts, palladium supported on non-functionalized low-surface nanofibers was the best anodic catalyst for the electrochemical reforming of ethanol in alkaline media, which was attributed to the specific physicochemical and textural properties of this material. In addition, the use of a Tokuyama membrane allowed to obtain the highest electrocatalytic activity in hydrogen production together with a suitable stability behavior. Under the optimized conditions, current density values up to 120 mA cm −2 at 1.4 V were obtained, leading to lower energy values for hydrogen production compared with those of water electrolysis in commercial alkaline electrolyzers. CONCLUSION: The choice of palladium supported on non-functionalized nanofibers as anodic catalyst and a Tokuyama membrane allows to obtain the best MEA configuration for the electrochemical reforming of ethanol for hydrogen production.

show abstract

Section: Resultsmentioning

confidence: 84%

Section: Methodsmentioning

confidence: 99%

Optimization of the catalytic support and membrane for the electrochemical reforming of ethanol in alkaline media

Calcerrada

Osa

Romero

et al. 2019

J of Chemical Tech & Biotech

Self Cite

View full text Add to dashboard Cite

show abstract

“…Nanodiamonds have a unique structure that allows the use of the material as an adsorbent. There have been a large number of works devoted to the study of the sorption properties of carbon materials published in recent decades [ 3 , 4 , 5 , 6 , 7 , 8 ].…”

Section: Introductionmentioning

confidence: 99%

Positron Spectroscopy of Nanodiamonds after Hydrogen Sorption

et al. 2018

View full text Add to dashboard Cite

The structure and defects of nanodiamonds influence the hydrogen sorption capacity. Positronium can be used as a sensor for detecting places with the most efficient capture of hydrogen atoms. Hydrogenation of carbon materials was performed from gas atmosphere. The concentration of hydrogen absorbed by the sample depends on the temperature and pressure. The concentration 1.2 wt % is achieved at the temperature of 243 K and the pressure of 0.6 MPa. The hydrogen saturation of nanodiamonds changes the positron lifetime. Increase of sorption cycle numbers effects the positron lifetime, as well as the parameters of the Doppler broadening of annihilation line. The electron-positron annihilation being a sensitive method, it allows detecting the electron density fluctuation of the carbon material after hydrogen saturation.

show abstract

“…In order to find an effective and economical way of storing hydrogen, an ideal material with high hydrogen storage capacity should be given higher priority [8]. Previous research has shown that the hydrogen adsorption capacity can increase by Ni-modified materials [9]. The effect of each parameter during the feeding process should be taken into consideration and understood carefully in order to maintain safety and to improve the efficiency of hydrogen storage.…”

Section: Introductionmentioning

confidence: 99%