Journal ArticleDOI
Pd clusters supported on amorphous, low-porosity carbon spheres for hydrogen production from formic acid.
Dmitri A. Bulushev,Dmitri A. Bulushev,Lyubov G. Bulusheva,Sergey Beloshapkin,Thomas Turner Pat O'connor,Alexander V. Okotrub,Kevin M. Ryan +6 more
TLDR
It is shown that boiling of the obtained spheres in 28 wt % HNO3 did not affect the shape and bulk structure of the spheres, but led to creation of a considerable amount of surface oxygen-containing functional groups and increase of the content of sp(2) hybridized carbon on the surface.Abstract:
Amorphous, low-porosity carbon spheres on the order of a few micrometers in size were prepared by carbonization of squalane (C30H62) in supercritical CO2 at 823 K. The spheres were characterized and used as catalysts’ supports for Pd. Near-edge X-ray absorption fine structure studies of the spheres revealed sp2 and sp3 hybridized carbon. To activate carbons for interaction with a metal precursor, often oxidative treatment of a support is needed. We showed that boiling of the obtained spheres in 28 wt % HNO3 did not affect the shape and bulk structure of the spheres, but led to creation of a considerable amount of surface oxygen-containing functional groups and increase of the content of sp2 hybridized carbon on the surface. This carbon was seen by scanning transmission electron microscopy in the form of waving graphene flakes. The H/C atomic ratio in the spheres was relatively high (0.4) and did not change with the HNO3 treatment. Palladium was deposited by impregnation with Pd acetate followed by reducti...read more
Citations
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Single Isolated Pd2+ Cations Supported on N-Doped Carbon as Active Sites for Hydrogen Production from Formic Acid Decomposition
Dmitri A. Bulushev,Monika Zacharska,Elena V. Shlyakhova,Andrey Chuvilin,Yina Guo,Sergey Beloshapkin,Alexander V. Okotrub,Lyubov G. Bulusheva +7 more
Abstract: Single-site heterogeneous catalysis with isolated Pd atoms was reported earlier, mainly for oxidation reactions and for Pd catalysts supported on oxide surfaces. In the present work, we show that single Pd atoms on nitrogen-functionalized mesoporous carbon, observed by aberration-corrected scanning transmission electron microscopy (ac STEM), contribute significantly to the catalytic activity for hydrogen production from vapor-phase formic acid decomposition, providing an increase by 2–3 times in comparison to Pd catalysts supported on nitrogen-free carbon or unsupported Pd powder. Some gain in selectivity was also achieved. According to X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure (NEXAFS) studies after ex situ reduction in hydrogen at 573 K, these species exist in a Pd2+ state coordinated by nitrogen species of the support. Extended density functional theory (DFT) calculations confirm that an isolated Pd atom can be the active site for the reaction, giving decompos...
Journal ArticleDOI
Anchoring IrPdAu Nanoparticles on NH2-SBA-15 for Fast Hydrogen Production from Formic Acid at Room Temperature.
TL;DR: The as-synthesized IrPdAu/NH2-SBA-15 possesses superior catalytic activity and 100% H2 selectivity with an initial turnover frequency (TOF) value comparable to the most effective heterogeneous catalysts ever published.
Journal ArticleDOI
Highly Stable Single-Atom Catalyst with Ionic Pd Active Sites Supported on N-Doped Carbon Nanotubes for Formic Acid Decomposition.
Olga Yu. Podyacheva,Dmitri A. Bulushev,Arina N. Suboch,Dmitry A. Svintsitskiy,A. S. Lisitsyn,Evgeny Modin,Andrey Chuvilin,Evgeny Yu. Gerasimov,Vladimir I. Sobolev,Valentin N. Parmon +9 more
TL;DR: The high stability of the single-atom Pd sites opens possibilities for using such catalysts in high-temperature reactions, and shows a high rate of gas-phase formic acid decomposition yielding hydrogen.
Journal ArticleDOI
Depositing CdS nanoclusters on carbon-modified NaYF4:Yb,Tm upconversion nanocrystals for NIR-light enhanced photocatalysis
TL;DR: A facile approach is presented to modify hydrophobic UCNs with a uniform carbon layer and enable them with hydrophilicity and surface functionalization and the products display good photocatalytic activity under visible light and obviously enhanced performance under Vis-NIR light.
Journal ArticleDOI
Factors Influencing the Performance of Pd/C Catalysts in the Green Production of Hydrogen from Formic Acid
Monika Zacharska,Lyubov G. Bulusheva,A. S. Lisitsyn,Sergey Beloshapkin,Yina Guo,Andrey Chuvilin,Elena V. Shlyakhova,Olga Yu. Podyacheva,James J. Leahy,Alexander V. Okotrub,Dmitri A. Bulushev +10 more
TL;DR: In all catalysts derived from Pd acetate, metal particles visible by conventional TEM had similar sizes, but the adsorption capacity towards CO responded strongly to N-doping of the carbon surface, and a decrease in the CO/Pd values was accompanied by a significant increase in the reaction rate.
References
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Journal ArticleDOI
Hydrogen production from formic acid decomposition at room temperature using a Ag-Pd core-shell nanocatalyst
Karaked Tedsree,Tong Li,Simon Jones,Chun Wong Aaron Chan,Kai Man Kerry Yu,Paul A. J. Bagot,Emmanuelle A. Marquis,George Davey Smith,Shik Chi Edman Tsang +8 more
TL;DR: It is reported that Ag nanoparticles coated with a thin layer of Pd atoms can significantly enhance the production of H₂ from formic acid at ambient temperature.
Journal ArticleDOI
Formic acid as a hydrogen source – recent developments and future trends
Martin Grasemann,Gábor Laurenczy +1 more
TL;DR: In this article, the state of research for heterogeneous and homogeneous formic acid dehydrogenation catalysts is reviewed in detail and an outlook on necessary development steps is presented.
Journal ArticleDOI
Tuning the acid/base properties of nanocarbons by functionalization via amination
Rosa Arrigo,Michael Hävecker,Sabine Wrabetz,Raoul Blume,Martin Lerch,James McGregor,Edward P. J. Parrott,J. Axel Zeitler,Lynn F. Gladden,Axel Knop-Gericke,Robert Schlögl,Dang Sheng Su +11 more
TL;DR: The functionalization procedure presented in this work allows high versatility and flexibility in tailoring the surface chemistry of nanocarbon material to specific needs in catalysis as well as electronic device materials.