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The present study aims to develop an electroanalytical method to determine one of the most significant antineoplastic agents, topotecan (TPT), using a novel and selective molecular imprinted polymer (MIP) method for the first time. The MIP was synthesized using the electropolymerization method using TPT as a template molecule and pyrrole (Pyr) as the functional monomer on a metal-organic framework decorated with chitosan-stabilized gold nanoparticles (Au-CH@MOF-5). The materials' morphological and physical characteristics were characterized using various physical techniques. The analytical characteristics of the obtained sensors were examined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). After all characterizations and optimizing the experimental conditions, MIP-Au-CH@MOF-5 and NIP-Au-CH@MOF-5 were evaluated on the glassy carbon electrode (GCE). MIP-Au-CH@MOF-5/GCE indicated a wide linear response of 0.4-70.0 nM and a low detection limit (LOD) of 0.298 nM. The developed sensor also showed excellent recovery in human plasma and nasal samples with recoveries of 94.41-106.16 % and 95.1-107.0 %, respectively, confirming its potential for future on-site monitoring of TPT in real samples. This methodology offers a different approach to electroanalytical procedures using MIP methods. Moreover, the high sensitivity and selectivity of the developed sensor were illustrated by the ability to recognize TPT over potentially interfering agents. Hence, it can be speculated that the fabricated MIP-Au-CH@MOF-5/GCE may be utilized in a multitude of areas, including public health and food quality., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Hydrazine borane (HB; N 2 H 4 BH 3 ) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni 0.22 @Ir 0.78 /OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h -1 at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni 0.22 @Ir 0.78 /OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni 0.22 @Ir 0.78 /OMS-2-catalyzed dehydrogenation of HB.

We reported the improved catalytic property of Pd (0) nanoparticles decorated on amine-functionalized graphene nanosheets (Pd/GNS-NH 2 ) for the hydrogenation of nitrophenol derivatives in the presence of NaBH 4 at moderate conditions. Pd/GNS-NH 2 nanocatalyst was synthesized by the deposition-reduction method. Sundry techniques such as ICP-OES, P-XRD, XPS, TEM, HR-TEM and EDX have been applied to explain the structure and morphology of the Pd/GNS-NH 2 nanocatalyst. The results show that the Pd (0) nanoparticles are perfectly dispersed on the surface of the GNS-NH 2 support material (d mean  = 1.38-2.63 nm). The catalytic activity of the Pd/GNS-NH 2 nanocatalyst was tested in the hydrogenation of nitrophenol derivatives in water in the presence of NaBH 4 as reductant and the excellent activity of nanocatalyst have been detected against 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol derivatives with 116.8, 65.9, 42.8 and 11.4 min -1 initial TOF values, respectively. Another important point is that the nanocatalyst has very high reusability performance (at 5th reuse between 71.5 and 91.5%) for the hydrogenation of nitrophenols. Finally, catalytic studies have been carried out at various temperatures to calculate the E a , ΔH ≠ and ΔS ≠ ., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We report the fabrication of a novel and highly active nanocatalyst system comprising electrospun carbon nanofiber (CNF)-supported ruthenium nanoparticles (NPs) (Ru@CNF), which can reproducibly be prepared by the ozone-assisted atomic layer deposition (ALD) of Ru NPs on electrospun CNFs. Polyacrylonitrile (PAN) was electropsun into bead-free one-dimensional (1D) nanofibers by electrospinning. The electrospun PAN nanofibers were converted into well-defined 1D CNFs by a two-step carbonization process. We took advantage of an ozone-assisted ALD technique to uniformly decorate the CNF support by highly monodisperse Ru NPs of 3.4 ± 0.4 nm size. The Ru@CNF nanocatalyst system catalyzes the hydrolytic dehydrogenation of methylamine borane (CH 3 NH 2 BH 3 ), which has been considered as one of the attractive materials for the efficient chemical hydrogen storage, with a record turnover frequency of 563 mol H 2 /mol Ru × min and an excellent conversion (>99%) under air at room temperature with the activation energy ( E a ) of 30.1 kJ/mol. Moreover, Ru@CNF demonstrated remarkable reusability performance and conserved 72% of its inherent catalytic activity even at the fifth recycle.

Herein we show that a previously unappreciated combination of CrAuPd alloy nanoparticles and amine-grafted silica support facilitates the liberation of CO-free H2 from dehydrogenation of formic acid with record activity in the absence of any additives at room temperature. Furthermore, their excellent catalytic stability makes them isolable and reusable heterogeneous catalysts in the formic acid dehydrogenation.

Intensive efforts have been devoted to the development of new materials for safe and efficient hydrogen storage. Among them, ammonia-borane appears to be a promising candidate due to its high gravimetric hydrogen storage capacity. Ammonia-borane can release hydrogen on hydrolysis in aqueous solution under mild conditions in the presence of a suitable catalyst. Herein, we report the synthesis of ruthenium(0) nanoparticles stabilized by dihydrogenphosphate anions with an average particle size of 2.9 ± 0.9 nm acting as a water-dispersible nanocatalyst in the hydrolysis of ammonia-borane. They provide an initial turnover frequency (TOF) value of 80 min -1 in hydrogen generation from the hydrolysis of ammonia-borane at room temperature. Moreover, the high stability of these ruthenium(0) nanoparticles makes them long-lived and reusable nanocatalysts for the hydrolysis of ammonia-borane. They provide 56,800 total turnovers and retain ~80% of their initial activity even at the fifth catalytic run in the hydrolysis of ammonia-borane at room temperature.

Today, the synthesis of well-defined metal nanoparticles stabilized by the metal-organic frameworks (MOFs), which provide high specific surface areas, tunable pore sizes, and guest interactable organic linkers, and the discovery of their unique properties are still challenging goals. The chemically robust zeolitic imidazole framework (ZIF) is a subclass of MOF. In this study, the microporous sodalite-like ZIF-8 (Zn(MeIM); MeIM = 2-methylimidazole) was selected as host matrix to stabilize guest iridium nanoparticles (IrNPs). The iridium loading was achieved via gas phase infiltration of Ir(COD)(MeCp) (methylcyclopentadienyl)(1,5-cyclooctadiene)iridium(i)) precursor followed by hydrogenolysis of the inclusion compound Ir(COD)(MeCp)@ZIF-8 to form the IrNPs@ZIF-8. The characterization of IrNPs@ZIF-8 by ICP-MS, P-XRD, XPS, (13)C MAS NMR, TEM, HRTEM, STEM, STEM-EDX, HAADF-STEM, DR-UV-vis, EA analyses and N(2)-adsorption-desorption techniques reveal the formation of well-dispersed iridium nanoparticles (3.3 ± 1.7 nm) within the framework of ZIF-8 (IrNPs@ZIF-8) by keeping the host framework intact. The catalytic application of IrNPs@ZIF-8 in terms of activity, selectivity, reusability and durability was demonstrated in the hydrogenation of cyclohexene and phenylacetylene under mild conditions, in which they were found to be highly active catalysts. Moreover, they show great durability against sintering and leaching throughout the catalytic runs that make them highly reusable catalysts. They retain their inherent catalytic activity even at the fifth catalytic run in the hydrogenation of cyclohexene and phenylacetylene.

Herein we report the development of a new and cost-effective nanocomposite catalyst for the hydrolysis of ammonia-borane (NH(3)BH(3)), which is considered to be one of the most promising solid hydrogen carriers because of its high gravimetric hydrogen storage capacity (19.6% wt) and low molecular weight. The new catalyst system consisting of copper nanoparticles supported on magnetic SiO(2)/CoFe(2)O(4) particles was reproducibly prepared by wet-impregnation of Cu(II) ions on SiO(2)/CoFe(2)O(4) followed by in situ reduction of the Cu(II) ions on the surface of magnetic support during the hydrolysis of NH(3)BH(3) and characterized by ICP-MS, XRD, XPS, TEM, HR-TEM and N(2) adsorption-desorption technique. Copper nanoparticles supported on silica coated cobalt(II) ferrite SiO(2)/CoFe(2)O(4) (CuNPs@SCF) act as highly active catalyst in the hydrolysis of ammonia-borane, providing an initial turnover frequency of TOF = 2400 h(-1) at room temperature, which is not only higher than all the non-noble metal catalysts but also higher than the majority of the noble metal based homogeneous and heterogeneous catalysts employed in the same reaction. More importantly, they were easily recovered by using a permanent magnet in the reactor wall and reused for up to 10 recycles without losing their inherent catalytic activity significantly, which demonstrates the exceptional reusability of the CuNPs@SCF catalyst.

Herein we report the discovery of an in situ generated, highly active nanocatalyst for the room temperature dehydrogenation of dimethylamine-borane in water. The new catalyst system consisting of ruthenium(0) nanoparticles stabilized by the hydrogenphosphate anion can readily and reproducibly be formed under in situ conditions from the dimethylamine-borane reduction of a ruthenium(III) precatalyst in tetrabutylammonium dihydrogenphosphate solution at 25 ± 0.1 °C. These new water dispersible ruthenium nanoparticles were characterized by using a combination of advanced analytical techniques. The results show the formation of well-dispersed ruthenium(0) nanoparticles of 2.9 ± 0.9 nm size stabilized by the hydrogenphosphate anion in aqueous solution. The resulting ruthenium(0) nanoparticles act as a highly active catalyst in the generation of 3.0 equiv. of H(2) from the hydrolytic dehydrogenation of dimethylamine-borane with an initial TOF value of 500 h(-1) at 25 ± 0.1 °C. Moreover, they provide exceptional catalytic lifetime (TTO = 11,600) in the same reaction at room temperature. The work reported here also includes the following results; (i) monitoring the formation kinetics of the in situ generated ruthenium nanoparticles, by using the hydrogen generation from the hydrolytic dehydrogenation of dimethylamine-borane as a catalytic reporter reaction, shows that sigmoidal kinetics of catalyst formation and concomitant dehydrogenation fits well to the two-step, slow nucleation and then autocatalytic surface growth mechanism, A → B (rate constant k(1)) and A + B → 2B (rate constant k(2)), in which A is RuCl(3)·3H(2)O and B is the growing, catalytically active Ru(0)(n) nanoclusters. (ii) Hg(0) poisoning coupled with activity measurements after solution infiltration demonstrates that the in situ generated ruthenium(0) nanoparticles act as a kinetically competent heterogeneous catalyst in hydrogen generation from the hydrolytic dehydrogenation of dimethylamine-borane. (iii) A compilation of kinetic data depending on the temperature and catalyst concentration is used to determine the dependency of reaction rate on catalyst concentration and the activation energy of the reaction, respectively., (This journal is © The Royal Society of Chemistry 2012)

The development of simply prepared and effective catalytic materials for dehydrocoupling/dehydrogenation of ammonia-borane (AB; NH(3)BH(3)) under mild conditions remains a challenge in the field of hydrogen economy and material science. Reported herein is the discovery of in situ generated ruthenium nanocatalyst as a new catalytic system for this important reaction. They are formed in situ during the dehydrogenation of AB in THF at 25 °C in the absence of any stabilizing agent starting with homogeneous Ru(cod)(cot) precatalyst (cod = 1,5-η(2)-cyclooctadiene; cot = 1,3,5-η(3)-cyclooctatriene). The preliminary characterization of the reaction solutions and the products was done by using ICP-OES, ATR-IR, TEM, XPS, ZC-TEM, GC, EA, and (11)B, (15)N, and (1)H NMR, which reveal that ruthenium nanocatalyst is generated in situ during the dehydrogenation of AB from homogeneous Ru(cod)(cot) precatalyst and B-N polymers formed at the initial stage of the catalytic reaction take part in the stabilization of this ruthenium nanocatalyst. Moreover, following the recently updated approach (Bayram, E.; et al. J. Am. Chem. Soc.2011, 133, 18889) by performing Hg(0), CS(2) poisoning experiments, nanofiltration, time-dependent TEM analyses, and kinetic investigation of active catalyst formation to distinguish single metal or in the present case subnanometer Ru(n) cluster-based catalysis from polymetallic Ru(0)(n) nanoparticle catalysis reveals that in situ formed Ru(n) clusters (not Ru(0)(n) nanoparticles) are kinetically dominant catalytically active species in our catalytic system. The resulting ruthenium catalyst provides 120 total turnovers over 5 h with an initial turnover frequency (TOF) value of 35 h(-1) at room temperature with the generation of more than 1.0 equiv H(2) at the complete conversion of AB to polyaminoborane (PAB; [NH(2)BH(2)](n)) and polyborazylene (PB; [NHBH](n)) units.

Osmium(0) nanoclusters stabilized by zeolite-Y framework were reproducibly prepared by a simple two step procedure involving the incorporation of osmium(III) cations into the zeolite matrix by ion-exchange, followed by their reduction within the cavities of zeolite with sodium borohydride in aqueous solution all at room temperature. The composition and morphology of osmium(0) nanoclusters stabilized by zeolite framework, as well as the integrity and crystallinity of the host material were investigated by using ICP-OES, XRD, XPS, SEM, TEM, HRTEM, TEM/EDX, mid-IR, far-IR spectroscopies, and N(2)-adsorption/desorption technique. The results of the multiprong analysis reveal the formation of osmium(0) nanoclusters within the cavities of zeolite-Y without causing alteration in the framework lattice, formation of mesopores, or loss in the crystallinity of the host material. More importantly, far-IR studies showed that after the reduction of Os(3+) cations by sodium borohydride the Na(+) cations reoccupy their authentic cation sites restoring the integrity of zeolite-Y. The catalytic activity of osmium(0) nanoclusters stabilized by zeolite framework was tested in the aerobic oxidation of activated, unactivated and heteroatom containing alcohols to carbonyl compounds and was found to provide high activity and selectivity even under mild conditions (80 degrees C and 1 atm O(2) or air). Moreover, they were found to be stable enough to be isolated and bottled as solid material, which can be reused as active catalyst under the identical conditions of the first run.

"Weakly ligated/labile ligand" nanoparticles, that is nanoparticles where only weakly coordinated ligands plus the desired catalytic reactants are present, are of fundamental interest. Described herein is a catalyst system for benzene hydrogenation to cyclohexane consisting of "weakly ligated/labile ligand" Ir(0) nanoparticles and aggregates plus dry-HCl formed in situ from commercially available [(1,5-COD)IrCl](2) plus 40 +/- 1 psig (approximately 2.7 atm) H(2) at 22 +/- 0.1 degrees C. Multiple control and other experiments reveal the following points: (i) that this catalyst system is quite active with a TOF (turnover frequency) of 25 h(-1) and TTO (total turnovers) of 5250; (ii) that the BF(4)(-) and PF(6)(-) iridium salt precursors, [(1,5-COD)Ir(CH(3)CN)(2)]BF(4) and [(1,5-COD)Ir(CH(3)CN)(2)]PF(6), yield inferior catalysts; (iii) that iridium black with or without added, preformed HCl cannot achieve the TOF of 25 h(-1) of the in situ formed Ir(0)/dry-HCl catalyst. However and importantly, CS(2) poisoning experiments yield the same activity per active iridium atom for both the Ir(0)/dry-HCl and Ir black/no-HCl catalysts (12.5 h(-1) Ir(1-)), but reveal that the Ir(0)/dry-HCl system is 10-fold more dispersed compared to the Ir(0) black catalyst. The simple but important and key result is that "weakly ligated/labile ligand" Ir(0) nanoparticles and aggregates have been made in situ as demonstrated by the fact that they have identical, per exposed Ir(0) activity within experimental error to Ir(0) black and that they have no possible ligands other than those desired for the catalysis (benzene and H(2)) plus the at best poor ligand HCl. As expected, the in situ catalyst is poorly stabilized, exhibiting only 60% of its initial activity in a second run of benzene hydrogenation and resulting in bulk metal precipitation. However, stabilization of the Ir(0) nanoparticles with a ca. 2-fold higher catalytic activity and somewhat longer lifetime for the complete hydrogenation of benzene was accomplished by supporting the Ir(0) nanoparticles onto zeolite-Y (TOF of 47 h(-1) and 8600 TTO under otherwise identical conditions). Also reported is the interesting result that Cl(-) (present as Proton Sponge x H(+)Cl(-)) completely poisons benzene hydrogenation catalysis, but not the easier cyclohexene hydrogenation catalysis under otherwise the same conditions, results that suggest different active sites for these ostensibly related hydrogenation reaction. The results suggest that synthetic routes to "weakly ligated/labile ligand" nanoparticles exhibiting improved catalytic performance is an important goal worthy of additional effort.

The preparation of ruthenium(0) nanoclusters supported on hydroxyapatite and their characterization by a combination of complementary techniques are described. The resultant ruthenium(0) nanoclusters provide high activity and reusability in the complete hydrogenation of aromatics under mild conditions (at 25 degrees C and with 42 psi initial H(2) pressure).

The hydrogenation of aromatics is a ubiquitous chemical transformation used in both the petrochemical and specialty industry and is important for the generation of clean diesel fuels. Reported herein is the discovery of a superior heterogeneous catalyst, superior in terms of catalytic activity, selectivity, and lifetime in the hydrogenation of aromatics in the solvent-free system under mild conditions (at 25 degrees C and 42 +/- 1 psig initial H(2) pressure). Ruthenium(0) nanoclusters stabilized by a nanozeolite framework as a new catalytic material is reproducibly prepared from the borohydride reduction of a colloidal solution of ruthenium(III)-exchanged nanozeolites at room temperature and characterized by using ICP-OES, XRD, XPS, DLS, TEM, HRTEM, TEM/EDX, mid-IR, far-IR, and Raman spectroscopy. The resultant ruthenium(0) nanoclusters hydrogenate neat benzene to cyclohexane with 100% conversion under mild conditions (at 25 degrees C and 42 +/- 1 psig initial H(2) pressure) with record catalytic activity (initial TOF = 5430 h(-1)) and lifetime (TTO = 177 200). They provide exceptional catalytic activity not only in the hydrogenation of neat benzene but also in the solvent-free hydrogenation of methyl substituted aromatics such as toluene, o-xylene, and mesitylene under otherwise identical conditions. Moreover, they are an isolable, bottleable, and reusable catalyst in the hydrogenation of neat aromatics. When the isolated ruthenium(0) nanoclusters are reused, they retain 92% of their initial catalytic activity even for the third run in the hydrogenation of neat benzene under the same conditions as those of the first run. The work reported here also includes (i) far-infrared spectroscopic investigation of nanozeolite, ruthenium(III)-exchanged-nanozeolite, and ruthenium(0) nanoclusters stabilized by a nanozeolite framework, indicating that the host framework remains intact after the formation of a nanozeolite framework stabilized ruthenium(0) nanoclusters; (ii) the poisoning experiments performed by using tricyclohexylphosphine (P(C(6)H(11))(3)) and 4-ethyl-2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane PC(6)H(11)O(3) to examine whether the ruthenium(0) nanoclusters are encapsulated in the cages or supported on the external surface of nanozeolite; (iii) a summary section detailing the main findings for the "green chemistry"; and (iv) a review of the extensive literature of benzene hydrogenation, which is also tabulated as part of the Supporting Information .

The preparation of Ru(0) nanoclusters stabilized by 3-aminopropyltriethoxysilane and their characterization by a combination of complementary techniques are described. These new Ru(0) nanoclusters provide high activity and unprecedented reusability as a heterogeneous catalyst in the dehydrogenation of dimethylamine-borane.

Herein we report the discovery of a superior dimethylamine-borane dehydrogenation catalyst, more active than the prior best heterogeneous catalyst (Jaska, C. A.; Manners, I. J. Am. Chem. Soc. 2004, 126, 9776) reported to date for the dehydrogenation of dimethylamine-borane. The new catalyst system consists of rhodium(0) nanoclusters stabilized by C(5)H(11)COO(-) anions and Me(2)H(2)N(+) cations and can reproducibly be formed from the reduction of rhodium(II) hexanoate during dehydrogenation of dimethylamine-borane at room temperature. Rhodium(0) nanoclusters in an average particle size of 1.9 +/- 0.6 nm Rh(0)(approximately 190) nanoclusters) provide 1040 turnovers over 26 h with a record initial turnover frequency (TOF) of 60 h(-1) (the average TOF value is 40 h(-1)) in the dehydrogenation of dimethylamine-borane, yielding 100% of the cyclic product (Me(2)NBH(2))(2) at room temperature. The work reported here also includes the full experimental details of the following major components: (i) Characterization of dimethylammonium hexanoate stabilized rhodium(0) nanoclusters by using TEM, STEM, EDX, XRD, UV-vis, XPS, FTIR, (1)H, (13)C, and (11)B NMR spectroscopy, and elemental analysis. (ii) Collection of a wealth of previously unavailable kinetic data to determine the rate law and activation parameters for catalytic dehydrogenation of dimethylamine-borane. (iii) Monitoring of the formation kinetics of the rhodium(0) nanoclusters by a fast dimethylamine-borane dehydrogenation catalytic reporter reaction (Watzky, M. A.; Finke, R. G. J. Am. Chem. Soc. 1997, 119, 10382) at various [Me(2)NH.BH(3)]/[Rh] ratios and temperatures. Significantly, sigmoidal kinetics of catalyst formation was found to be well fit to the two-step, slow nucleation and then autocatalytic surface growth mechanism, A --> B (rate constant k(1)) and A + B --> 2B (rate constant k(2)), in which A is [Rh(C(5)H(11)CO(2))(2)](2) and B is the growing, catalytically active rhodium(0) nanoclusters. (iv) Mercury(0) and CS(2) poisoning and nanofiltration experiments to determine whether the dehydrogenation of dimethylamine-borane catalyzed by the dimethylammonium hexanoate stabilized rhodium(0) nanoclusters is homogeneous or heterogeneous catalysis.

Sodium borohydride, NaBH4, has been considered the most attractive hydrogen-storage material for portable fuel cell applications, as it provides a safe and practical means of producing hydrogen. In a recent communication (Zahmakiran, M.; Ozkar, S. Langmuir 2008, 24, 7065), we have reported a record total turnover number (TTON) of 103 200 mol H2/mol Ru and turnover frequency (TOF) up to 33 000 mol H2/mol Ru x h obtained by using intrazeolite ruthenium(0) nanoclusters in the hydrolysis of sodium borohydride. Here we report full details of the kinetic studies on the intrazeolite ruthenium(0) nanoclusters catalyzed hydrolysis of sodium borohydride in both aqueous and basic solutions. Expectedly, the intrazeolite ruthenium(0) nanoclusters show unprecedented catalytic lifetime, TTON = 27 200 mol H2/mol Ru, and TOF up to 4000 mol H2/mol Ru x h in the hydrolysis of sodium borohydride in basic solution (5% wt NaOH) as well. More importantly, the intrazeolite ruthenium(0) nanoclusters are isolable, bottleable, redispersible, and yet catalytically active. They retain 76% or 61% of their initial catalytic activity at the fifth run with a complete release of hydrogen in aqueous and basic medium, respectively. The intrazeolite ruthenium(0) nanoclusters were isolated as black powder and characterized by using a combination of advanced analytical techniques including XRD, HRTEM, TEM-EDX, SEM, XPS, ICP-OES, and N2 adsorption.

The use of microporous materials with ordered porous structures as the hosts to encapsulate metal nanoclusters has attracted particular interest in catalysis because the pore size restriction could limit the growth of nanoclusters and lead to an increase in the percentage of the catalytically active surface atoms. This letter reports the preparation of ruthenium(0) nanoclusters stabilized by the framework of Zeolite-Y by using a simple, easy, efficient method and their superb catalytic activities in two important reactions: the hydrogenation of arenes (benzene, toluene, o-xylene, mesitylene) and the hydrolysis of sodium borohydride, all at room temperature. Particularly, the intrazeolite ruthenium(0) nanoclusters exhibit unprecedented catalytic activity in the hydrogenation of neat benzene at 22.0 +/- 0.1 degrees C and 40 +/- 1 psig H2 with a record TOF of 1040 mol benzene/mol Ru . h.