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Lipase enzyme was embedded within silica nanoparticles with oil-filled core-shell structure. The enzyme embedded within such architecture retained all of its activity and showed high catalytic performance both in water and in organic media with optimal stability and recyclability.

p‐Nitrophenol (PNP) has aroused much concern due to its high toxicity in industrial wastewater and drinking water. Herein, we designed a new plasmonic RuPd/HxMoO3–y catalyst synthesized by a simple impregnation method, followed by H2 atmosphere reduction. The synthesized RuPd/HxMoO3–y hybrid, having RuPd alloy nanoparticles (NPs) anchored on HxMoO3–y, namely hydrogen‐doped molybdenum oxide support, shows a strong localized surface plasmon resonance (LSPR) absorption peak at around 639 nm. Photocatalytic activity of Ru/HxMoO3–y hybrid for the reduction of PNP to p‐aminophenol (PAP) under visible light irradiation can be dramatically improved by alloying with Pd atoms. More importantly, a reasonable mechanism for PNP reduction is proposed. We find that synergetic effect between HxMoO3–y and RuPd alloy NPs of RuPd/HxMoO3–y plays a vital role in photocatalytic reduction, in which RuPd alloy NPs act as the active species and plasmonic HxMoO3–y acts as electron‐donation centre. [ABSTRACT FROM AUTHOR]

Electrochemical CO 2 reduction (CO 2 RR) to produce syngas (CO and H 2) is a highly attractive way for achieving carbon neutrality. However, it remains a challenge due to the lack of high-efficiency electrocatalysts that enables controllable CO/H 2 ratio syngas production. Herein, aminopolymer functionalized hollow carbon spheres incorporating Ag NPs (Ag-P@HCS) are developed, which function as active catalysts for syngas electrosynthesis. The introduction of aminopolymers results in finely improved dispersion of Ag NPs and increased CO 2 adsorption of Ag-P@HCS, thereby altering its CO 2 RR performance. As a result, Ag-P@HCS achieves a 4.6-fold increase in the Faradaic efficiency of CO when compared to the amiopolymer-free analog (Ag-HCS) at − 0.8 V vs. RHE. More importantly, the controllable CO/H 2 ratios (1.09 – 2.54) can be obtained for Ag-P@HCS over a wide potential window, which is capable of meeting the specific requirements for industrial production. This work demonstrates the potential of aminopolymer functionalization for designing high-performance CO 2 RR electrocatalysts. [Display omitted] • Aminopolymer modified hollow carbon spheres incorporating Ag nanoparticles were reported. • The catalyst was used for efficient syngas (CO and H 2) production by electrochemical CO 2 reduction. • The roles of aminopolymer for the enhancement of CO 2 electroreduction performance were revealed. • Controllable CO/H 2 ratio (1.09 – 2.54) production was achieved. [ABSTRACT FROM AUTHOR]

Pd nanoparticles (NPs) supported on Ti-doped graphitic carbon nitride (g-C3N4) were synthesized by a deposition-precipitation route and a subsequent reduction with NaBH4. The features of the NPs were studied by XRD, TEM, FTIR, XPS, EXAFS and N2-physisorption measurements. It was found that the NPs had an average size of 2.9 nm and presented a high dispersion on the surface of Ti-doped g-C3N4. Compared to Pd loaded on pristine g-C3N4, the Pd NPs supported on Ti-doped g-C3N4 exhibited a high catalytic activity in formic acid dehydrogenation in water at room temperature. The enhanced activity could be attributed to the small Pd NPs size, as well as the strong interaction between Pd NPs and Ti-doped g-C3N4. [ABSTRACT FROM AUTHOR]

One-pot reaction involving Pd-catalyzed H2O2 production from H2 and O2 and Ti-catalyzed successive oxidation with H2O2 in a single reaction vessel is an alluring strategy for the synthesis of targeted chemicals in terms of sustainability and economic competitiveness. In this study, a yolk-shell nanostructured catalyst, consisting of Pd nanoparticles (NPs) with core diameter ca. 4.0 nm and a porous titanosilicate shell of ca. 15 nm thickness, was fabricated by using an oil-in-water (O/W) microemulsion-based interfacial self-assembly approach. Compared with prototype titanosilicate-supported Pd NP catalysts and core-shell structured analogues, the yolk-shell nanostructured catalyst exhibited superior catalytic efficiency in the one-pot oxidation reaction of sulfides with 83 % H2O2 utilization efficiency, because of the productive effect of the titanosilicate shell in limiting the diffusion of H2O2 generated in situ over the encapsulated Pd NPs and the efficient access of the H2O2 to the neighboring active Ti sites. This study provides promising avenues for the development of multifunctional nanostructured catalysts that are useful for one-pot reactions. [ABSTRACT FROM AUTHOR]

A straightforward aqueous synthesis of MoO3− x nanoparticles at room temperature was developed by using (NH4)6Mo7O24⋅4 H2O and MoCl5 as precursors in the absence of reductants, inert gas, and organic solvents. SEM and TEM images indicate the as-prepared products are nanoparticles with diameters of 90-180 nm. The diffuse reflectance UV-visible-near-IR spectra of the samples indicate localized surface plasmon resonance (LSPR) properties generated by the introduction of oxygen vacancies. Owing to its strong plasmonic absorption in the visible-light and near-infrared region, such nanostructures exhibit an enhancement of activity toward visible-light catalytic hydrogen generation. MoO3− x nanoparticles synthesized with a molar ratio of MoVI/MoV 1:1 show the highest yield of H2 evolution. The cycling catalytic performance has been investigated to indicate the structural and chemical stability of the as-prepared plasmonic MoO3− x nanoparticles, which reveals its potential application in visible-light catalytic hydrogen production. [ABSTRACT FROM AUTHOR]

Metal-support interactions (MSIs) and particle size play important roles in catalytic reactions. For the first time, silver nanoparticles supported on CeO2-SBA-15 supports are reported that possess tunable particle size and MSIs, as prepared by microwave (MW) irradiation, owing to strong charge polarization of CeO2 clusters (i.e., MW absorption). Characterizations, including TEM, X-ray photoelectron spectroscopy, and extended X-ray absorption fine structure, were carried out to disclose the influence of CeO2 contents on the Ag particle size, MSI effect between Ag nanoparticles and CeO2-SBA-15 supports, and the strong MW absorption of CeO2 clusters that contribute to the MSIs during Ag deposition. The Ag particle sizes were controllably tuned from 1.9 to 3.9 nm by changing the loading amounts of CeO2 from 0.5 to 2.0 wt %. The Ag nanoparticle size was predominantly responsible for the high turnover frequency (TOF) of 0.41 min−1 in ammonia borane dehydrogenation, whereas both particle size and MSIs contributed to the high TOF of 555 min−1 in 4-nitrophenol reduction for Ag/0.5CeO2-SBA-15, which were twice as large as those of Ag/SBA-15 without CeO2 and Ag/CeO2-SBA-15 prepared by conventional oil-bath heating. [ABSTRACT FROM AUTHOR]

• PdAg nanoparticles are dispersed uniformly within N-doped microporous hollow carbon spheres. • PdAg@NMHCS-0.6-500 exhibits extraordinary activity for CO 2 hydrogenation to formate showing high TON of 2750 after 24 h. • Different carbonization temperatures cause changes in PdAg NPs dispersion and the formation of Pd N bonds. • N-doped MHCS reduces the activation energy for CO 2 hydrogenation to formate. Here, we report a general synthesis approach to produce PdAg nanoparticles (NPs) that are dispersed uniformly within N-doped microporous hollow carbon spheres (NMHCS) for hydrogenation of CO 2 to formate. The optimized PdAg@NMHCS catalyst, which was obtained by using an optimized amount of ethylenediamine as the nitrogen source and pyrolyzed at 500 °C, exhibits extraordinary activity for CO 2 hydrogenation to formate, showing a high turnover number (TON) of 640 and 2750 at 100 °C after 2 and 24 h, respectively. Experiments reveal that different carbonization temperatures cause changes in the surface area, the nitrogen content of NMHCS, PdAg NPs dispersion, and the formation of Pd-N bonds. Upon consideration of kinetic analyses, N-doped MHCS are not only effective for the adsorption of CO 2 due to the doping of nitrogen but also would reduce the activation energy barrier for CO 2 hydrogenation to formate by facilitating including CO 2 adsorption/insertion step and H 2 dissociation step. [ABSTRACT FROM AUTHOR]

Keywords: Dehydrogenation; Heterogeneous catalysis; Pd nanoparticles; - interaction; Surface modification EN Dehydrogenation Heterogeneous catalysis Pd nanoparticles - interaction Surface modification 5834 5834 1 12/07/20 20201204 NES 201204 B The Front Cover b shows Pd nanoparticle catalysts modified with pyrene-thiol ligands on carbon supports for aerobic oxidative dehydrogenation of amines to imines. In their Communication, T. Yoshii et al. experimentally and theoretically demonstrate that the rate-limiting imine product desorption is boosted as a result of the steric hindrance of the ligands, and the catalytic stability is significantly improved by the - interactions between catalyst and support, which make this material an active and stable catalyst for the amine dehydrogenation reaction. Dehydrogenation, Heterogeneous catalysis, Pd nanoparticles, - interaction, Surface modification. [Extracted from the article]