Limits...
Advances in Pd Nanoparticle Size Decoration of Mesoporous Carbon Spheres for Energy Application.

Zielinska B, Michalkiewicz B, Mijowska E, Kalenczuk RJ - Nanoscale Res Lett (2015)

Bottom Line: Pd nanoparticles with different sizes and diameter distributions were successfully deposited on the surface of disordered mesoporous carbon spheres (DMHCS).Two methods of synthesis (reflux and impregnation) and two Pd precursors (palladium (II) acetyloacetonate (Pd(acac) 2) and palladium (II) acetate (Pd(OAc)2)) were investigated and compared for the preparation of Pd-decorated DMHCS.It was found that the Pd nanoparticle content, size, and diameter distribution have a noticeable influence on H2 storage capacity.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical and Environment Engineering, West Pomeranian University of Technology, Szczecin, Pułaskiego 10, 70-322, Szczecin, Poland. bzielinska@zut.edu.pl.

ABSTRACT
Pd nanoparticles with different sizes and diameter distributions were successfully deposited on the surface of disordered mesoporous carbon spheres (DMHCS). The size and diameter distribution of the Pd particles were controlled by the application of different experimental conditions. Two methods of synthesis (reflux and impregnation) and two Pd precursors (palladium (II) acetyloacetonate (Pd(acac) 2) and palladium (II) acetate (Pd(OAc)2)) were investigated and compared for the preparation of Pd-decorated DMHCS. The hydrogen storage properties of the pristine DMHCS and Pd-modified DMHCS at 40 °C and a pressure range of 0-45 bar were studied. The results showed that Pd-supported carbon samples synthesized in the presence of Pd(OAc)2 exhibited enhanced hydrogen storage capacity in respect to the pristine DMHCS. The maximum hydrogen storage of 0.38 wt.% exhibited the sample with the Pd nanoparticle diameter distribution of 2-14 nm and the average Pd crystallite size of 7.6 nm. It was found that the Pd nanoparticle content, size, and diameter distribution have a noticeable influence on H2 storage capacity.

No MeSH data available.


Related in: MedlinePlus

XRD patterns (upper panel) and Raman spectra (bottom panel) for a DMHCS, b Pd-I1, c Pd-R1, d Pd-I2, and e Pd-R2
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4627970&req=5

Fig3: XRD patterns (upper panel) and Raman spectra (bottom panel) for a DMHCS, b Pd-I1, c Pd-R1, d Pd-I2, and e Pd-R2

Mentions: The crystallographic composition of the synthesized samples was studied via X-ray diffraction (XRD). Figure 3 (upper panel) shows the XRD patterns of the pristine DMHCS (pattern a) and Pd nanoparticle-decorated DMHCS (patterns: b Pd-I1, c Pd-R1, d Pd-I2, e Pd-R2). XRD pattern of DMHCS shows two broad diffraction peaks at 2θ value of 25° and 45° corresponding to the (002) and (100) planes of graphitic carbon, respectively [18]. No diffraction peaks corresponding to the new phase of palladium are found for Pd-I1. The absence of the reflections for palladium could result from the low concentration of Pd nanoparticles deposited on DMHCS (below the detection limit of XRD). It indicates that using Pd(acac)2 as the precursor together with impregnation method did not induce the deposition of Pd nanoparticles on the surface of DMHCS. For Pd-R1, Pd-I2, and Pd-R2 samples, intense peaks at 2θ value of 40°, 46°, 68°, 82°, and 87° are observed. All those reflections are characteristic to the palladium phase (JCPDS card no. 50-0681) and correspond to the (111), (200), (220), (311), and (222) planes, respectively [19]. Here, it is clearly seen that the intensity of the Pd reflections increases in the following order: Pd-R1 > Pd-I2 > Pd-R2, indicating increased crystallinity. The calculated average Pd crystallite size is about 5.3 nm (Pd-R1), 6.4 nm (Pd-I2), and 7.6 nm (Pd-R2). These results are consistent with the TEM analysis of the samples.Fig. 3


Advances in Pd Nanoparticle Size Decoration of Mesoporous Carbon Spheres for Energy Application.

Zielinska B, Michalkiewicz B, Mijowska E, Kalenczuk RJ - Nanoscale Res Lett (2015)

XRD patterns (upper panel) and Raman spectra (bottom panel) for a DMHCS, b Pd-I1, c Pd-R1, d Pd-I2, and e Pd-R2
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4627970&req=5

Fig3: XRD patterns (upper panel) and Raman spectra (bottom panel) for a DMHCS, b Pd-I1, c Pd-R1, d Pd-I2, and e Pd-R2
Mentions: The crystallographic composition of the synthesized samples was studied via X-ray diffraction (XRD). Figure 3 (upper panel) shows the XRD patterns of the pristine DMHCS (pattern a) and Pd nanoparticle-decorated DMHCS (patterns: b Pd-I1, c Pd-R1, d Pd-I2, e Pd-R2). XRD pattern of DMHCS shows two broad diffraction peaks at 2θ value of 25° and 45° corresponding to the (002) and (100) planes of graphitic carbon, respectively [18]. No diffraction peaks corresponding to the new phase of palladium are found for Pd-I1. The absence of the reflections for palladium could result from the low concentration of Pd nanoparticles deposited on DMHCS (below the detection limit of XRD). It indicates that using Pd(acac)2 as the precursor together with impregnation method did not induce the deposition of Pd nanoparticles on the surface of DMHCS. For Pd-R1, Pd-I2, and Pd-R2 samples, intense peaks at 2θ value of 40°, 46°, 68°, 82°, and 87° are observed. All those reflections are characteristic to the palladium phase (JCPDS card no. 50-0681) and correspond to the (111), (200), (220), (311), and (222) planes, respectively [19]. Here, it is clearly seen that the intensity of the Pd reflections increases in the following order: Pd-R1 > Pd-I2 > Pd-R2, indicating increased crystallinity. The calculated average Pd crystallite size is about 5.3 nm (Pd-R1), 6.4 nm (Pd-I2), and 7.6 nm (Pd-R2). These results are consistent with the TEM analysis of the samples.Fig. 3

Bottom Line: Pd nanoparticles with different sizes and diameter distributions were successfully deposited on the surface of disordered mesoporous carbon spheres (DMHCS).Two methods of synthesis (reflux and impregnation) and two Pd precursors (palladium (II) acetyloacetonate (Pd(acac) 2) and palladium (II) acetate (Pd(OAc)2)) were investigated and compared for the preparation of Pd-decorated DMHCS.It was found that the Pd nanoparticle content, size, and diameter distribution have a noticeable influence on H2 storage capacity.

View Article: PubMed Central - PubMed

Affiliation: Institute of Chemical and Environment Engineering, West Pomeranian University of Technology, Szczecin, Pułaskiego 10, 70-322, Szczecin, Poland. bzielinska@zut.edu.pl.

ABSTRACT
Pd nanoparticles with different sizes and diameter distributions were successfully deposited on the surface of disordered mesoporous carbon spheres (DMHCS). The size and diameter distribution of the Pd particles were controlled by the application of different experimental conditions. Two methods of synthesis (reflux and impregnation) and two Pd precursors (palladium (II) acetyloacetonate (Pd(acac) 2) and palladium (II) acetate (Pd(OAc)2)) were investigated and compared for the preparation of Pd-decorated DMHCS. The hydrogen storage properties of the pristine DMHCS and Pd-modified DMHCS at 40 °C and a pressure range of 0-45 bar were studied. The results showed that Pd-supported carbon samples synthesized in the presence of Pd(OAc)2 exhibited enhanced hydrogen storage capacity in respect to the pristine DMHCS. The maximum hydrogen storage of 0.38 wt.% exhibited the sample with the Pd nanoparticle diameter distribution of 2-14 nm and the average Pd crystallite size of 7.6 nm. It was found that the Pd nanoparticle content, size, and diameter distribution have a noticeable influence on H2 storage capacity.

No MeSH data available.


Related in: MedlinePlus