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The development of non-noble metal catalysts for selective hydrogenation still remains a challenge. Herein, NiCu@carbon core–shell nanoparticles supported on Al2O3 (NiCu@C/Al2O3) were prepared, which showed enhanced catalytic performance of acetylene-selective hydrogenation in comparison with NiCu/Al2O3 without carbon encapsulation. In detail, NiCu@C/Al2O3 displayed high ethylene selectivity (>86%) even at an acetylene conversion of 100% and excellent stability (>90 h). Thus, NiCu@C/Al2O3 exhibited great potential as an alternative to Pd-based catalysts for acetylene-selective hydrogenation. [ABSTRACT FROM AUTHOR]

Citric acid (CA) modified Ni3P catalysts with small particle sizes were prepared by H2 temperature-programmed reduction (H2-TPR) of the precursors, which were prepared by co-precipitation with Ni(NO3)2·6H2O and (NH4)2HPO4, using citric acid as the chelating agent and calcining under a N2 atmosphere. The catalytic activity of the prepared catalysts was tested in the aqueous phase reforming (APR) and hydrogenolysis of glycerol to 1,2-propanediol (1,2-PDO). The effects of the CA/Ni molar ratio and reaction conditions (temperature, pressure, and time) on APR and hydrogenolysis of glycerol were investigated. The CA(1)–Ni3P catalyst exhibited the best performance at 220 °C, 0.5 MPa N2, and 8 h with 74.6% glycerol conversion and 43.2% selectivity of 1,2-PDO. The prepared CA(x)–Ni3P catalysts were characterized by XRD, N2 adsorption, Raman spectroscopy, CO-chemisorption and TEM. The addition of CA significantly enhanced the dispersion of Ni species in the precursors and enlarged the surface area of the catalyst. The residual carbonaceous species after calcination in N2 prevented the aggregation of Ni3P particles and promoted the reduction of the precursors. Compared with the unmodified Ni3P and CA(x)–Ni3P calcined in air, the CA(x)–Ni3P calcined in N2 with a smaller average particle size exhibited higher catalytic activities. [ABSTRACT FROM AUTHOR]

To achieve the construction of efficient photocatalytic H2 generation systems, developing highly active and durable earth-abundant H2 generation cocatalyst is still a challenge. In this paper, we construct a noble-metal-free Ni3P–Ni composite, which displays strong chemical stability and high-efficiency as a cocatalyst to enhance the visible-induced photocatalytic activities in H2 generation of g-C3N4. Ni3P–Ni/g-C3N4 is prepared by one-step annealing of amorphous Ni–P nanoparticles and g-C3N4. The result verifies that both Ni3P and metallic Ni worked as electron cocatalysts and significantly enhanced the visible light H2 generation over g-C3N4. The optimum composite 2.0 wt.% Ni3P–Ni/g-C3N4 exhibits a high H2 generation rate of 203.3 μmol g−1 h−1, which is 1.6, 2.7, and 53.5 times as much as those obtained on Ni3P/g-C3N4, Ni/g-C3N4, and pure g-C3N4 respectively. Photoluminescence and photoelectrochemical analysis confirm that the metallic Ni plays multifunctional roles in boosting the H2 generation under visible light, which could both accept the photo-generated electrons from g-C3N4 and enhance the electron transfer to Ni3P for further H2 generation. This investigation provides a route to the rational design and development of earth-abundant metal phosphide and metal composites, which could be utilized as noble-metal-free cocatalysts for the improvement of H2 generation activity. Spherical Ni3P–Ni particles with metallic Ni spread over the inner and outer surface of Ni3P sphere was synthesized and hybrid with g-C3N4. The specific structure of spherical Ni3P–Ni leads to adequate contact area between ternary Ni3P, Ni, and g-C3N4. Ni with high electrical conductivity could act as an electron transfer bridge between g-C3N4 and Ni3P, leading to effective charge separation and enhanced photocatalytic hydrogen generation. [ABSTRACT FROM AUTHOR]

The influence of the promoter nature and of a modifier in (K)(Me)MoS2/Al2O3 (Me=Fe, Co, Ni) catalysts on the conversion and selectivity of products of synthesis gas conversion to alcohols and jnl oxygenates was investigated. Relationships between promoter nature, hydrocarbon chain length and selectivity in the formed alcohols were established. Electronic structure of a promoter atom in an active site (AS) was found to strongly affect selectivity of alcohol formation. Promotion of the S‐edge by Fe, Co or Ni suppressed hydrogen activation, which resulted in a lower synthesis gas conversion. Promotion of the M‐edge by Fe, Co, or Ni entailed the formation of double vacancies which are active sites of synthesis gas conversion. Potassium affected the oxophilicity of Mo atoms and reduced Co/Ni‐promoted MoS AS. It decreased the probability of C−O bond breaking in the adsorbed intermediate and shifted selectivity from the formation of alkyl towards alkoxide fragments over these catalysts. [ABSTRACT FROM AUTHOR]

Hydrogen is known as the fuel for 21st century, the best and clean method to produce hydrogen is electrolysis of water. The oxygen evolution reaction (OER) is of vital position in water splitting, enabling the production of clean hydrogen fuel and contributing to renewable energy solutions. However, the inherently sluggish nature of the OER presents a major challenge for practical water electrolysis but at the same time electrocatalysts play a pivotal role by overcoming this challenge through accelerating the reaction kinetics and reducing the energy requirements. In the realm of electrocatalysts for OER, cobalt-based materials have gained significant attention due to their low overpotential and cost-effectiveness. Among prepared catalysts, the CoSe/CoO heterostructure has emerged as a standout performer, offering an optimal balance of efficiency and minimal overpotential. This electrocatalyst exhibits exceptional electrochemical performance, featuring a low 1.31 V onset potential (vs. RHE) and a mere 170 mV overpotential at a current density of 40 mA/cm2 for OER, setting a new standard for Co-based catalysts. Moreover, the CoSe/CoO heterostructure surpasses Co based bench mark electrocatalysts by displaying the lowest overpotential. Moreover, when subjected to controlled potential electrolysis at 1.65 V (vs. RHE) with a stable current density of 60 mA/cm2, it showcases remarkable electrochemical stability, affirming its practicality for real-world applications. The hydrothermal synthesis of CoSe, CoO, and their heterostructure (CoSe/CoO) represents a straightforward and accessible approach, rendering them as promising candidates for water splitting, specifically in the context of oxygen evolution. These outstanding results achieved with non-precious metal electrocatalysts open new avenues for practical OER applications, providing a platform for the scientific community to advance the development of effective electrocatalysts using non-noble metals in the field of electrochemical water splitting. • The prepared CoSe/CoO demonstrates remarkable OER activity compared to benchmark Co-based electrocatalysts. • The CoSe/CoO reveals excellent durability and stability which demonstrate it as a stable and efficient OER catalyst. • The CoSe/CoO illustrates competitive OER activity, with low overpotentials (η) of 170 mV at 40 mAcm−2 current density. • Results highlight its standing as cost effective, alternative and highly efficient electrocatalyst for OER. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of electrolysis of water is the major challenge which hampers the practical dissociation of water in H 2 and O 2 gas. Electrocatalysts are particularly required to enhance the performance of the water splitting process. In this manuscript, the catalytic performance of nickel selenide/nickel oxide (NiSe/NiO) heterostructure and its counter parts are bestowed for water splitting. The formation of synthesized materials along with phase structure were characterized by the XRD and the SEM was used for surface morphology. Among reported electrocatalysts, NiSe/NiO heterostructure has emerged as the best electrocatalyst for OER. It commences oxygen evolution at 1.34 V with minimum overpotential of 110 mV even at 20 mA/cm2. Chronoamperometry reveals excellent electrochemical stability for the extended period of 21 h for heterostructure electrocatalyst. The kinetic study has recommended NiSe/NiO as an adequate electrocatalyst for OER having Tafel slope of 43.56 mV/dec. These results surpass benchmark precious metal based electrocatalysts as well as electrocatalysts based on Ni. This development dispenses earth abundant, exceedingly efficient and extremely stable, non-precious metal based electrocatalysts for practical electrolysis of water. • One-pot synthesis yields NiSe/NiO heterostructure electrocatalyst with impressive OER activity. • Exceptional stability of NiSe/NiO heterostructure validates its suitability as a durable OER catalyst. • Competitive OER performance: low overpotentials (η) of 110 mV @ 20 mAcm-2, small Tafel slope (∼43 mV/dec in 1.0 M KOH). • NiSe/NiO emerges as a cost-effective alternative to noble metal-based OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: Ni–W hydrodesulfurization (HDS) catalysts supported on MCM-41 synthesized from two different silica sources (sodium silicate hydrate and tetraethylorthosilicate) as well as on Na+ or K+ ion exchanged MCM-41 were prepared. These catalysts were used to investigate the influence of the surface properties of MCM-41 on the performance of HDS catalysts with DBT as the model molecule. The XRD and N2 adsorption results indicated that the MCM-41 prepared from tetraethylorthosilicate (MCM-41(T)) exhibited the best structural properties. The mesostructure of MCM-41 synthesized from sodium silicate (MCM-41(S)) remained after ion exchange with Na2C2O2 and K2C2O2. Both pyridine FT-IR and Hammett indicators showed that only MCM-41(S) possessed some Brönsted and Lewis acid sites. Ni–W/MCM-41(S) showed the highest HDS and hydrogenation activities. The introduction of Na+ and K+ strongly inhibited the hydrogenation activity of Ni–W/MCM-41(S) but enhanced its hydrogenolysis activity. UV–vis and TPR studies indicated that the introduction of Na+ and K+ into MCM-41(S) may lead to the segregation of surface Ni species and may hinder the reducibility of the supported Ni–W oxides. Spillover hydrogen, which is “trapped” by Na+ and K+, may play an important role in the HDS activity and selectivity of Ni–W catalysts. [Copyright &y& Elsevier]

Abstract: Siliceous MCM-41-supported nickel phosphides from a precursor with a Ni/P atomic ratio of 3, 2, 1.25, 1, 0.5, or were prepared by in situ reduction. A high heating rate and a multistep program were used to prepare the supported nickel phosphides. The in situ reduction method proved superior to the traditional reduction–passivation–rereduction method. The timely removal of local moisture from the surface during reduction is crucial to obtaining a high hydrodesulfurization (HDS) performance of the phosphide catalysts. The precursors were characterized by TPR to investigate the reactions involved in phosphide preparation, and the structures of the resulting nickel phosphides were characterized by means of 31P NMR and XRD. Nickel phosphide formation may start with the reduction of NiO to Ni, and the Ni metal may assist phosphide formation in the reduction of nickel-rich precursors. Nickel-rich phosphides exhibited much higher HDS activity than phosphorus-rich phosphides prepared by the in situ reduction method. Reduction of the precursor with Ni/P=2 yielded Ni12P5/ MCM-41, whereas reduction of the precursor with Ni/P=1.25 produced Ni2P/MCM-41. As in the traditional reduction–passivation–rereduction method, a small excess of phosphorus in the precursors is also needed to obtain the desired nickel-rich phosphides by the in situ reduction method. Ni2P/MCM-41 was the most active catalyst in the HDS of dibenzothiophene among all of the supported nickel phosphides prepared by the in situ reduction method. [Copyright &y& Elsevier]

Ni-Mo, Co-Mo, Ni-W and Pt were supported over siliceous MCM-41 (Si-MCM-41) or the proton-exchanged Si-MCM-41 (H+-MCM-41) in order to investigate the effect of support surface modification on the performance of the catalysts. The prepared catalysts were evaluated by the hydrodesulfurization (HDS) of dibenzothiophene (DBT). It is indicated that the supported Ni-Mo sulfides exhibited the highest HDS activity regardless of the support, and that Ni-W sulfides showed the highest hydrogenation activity. The H+-MCM-41-supported Ni-Mo, Ni-W or Pt catalyst performed much better in HDS of DBT than the Si-MCM-41-supported counterpart. From the relative selectivity of cyclohexylbenzene (CHB) to biphenyl (BP) (SCHB/SBP), it could be concluded that the higher HDS performance of H+-MCM-41-supported catalysts may be attributed to the enhanced hydrogenation activity. Nevertheless, a little difference in HDS activity was observed for Co-Mo sulfides supported on Si-MCM-41 or H+-MCM-41. Since the cleavage of sulfur atoms mainly takes the route of hydrogenolysis in HDS of DBT catalyzed by Co-Mo sulfides, the improvement in hydrogenation activity was not significant for Co-Mo sulfides when Si-MCM-41 was ion-exchanged with HNO3. TPR study showed that the profiles of Ni-Mo/Si-MCM-41 and Ni-W/Si-MCM-41 changed markedly after the proton exchange of Si-MCM-41 while the profile of Co-Mo/Si-MCM-41 changed a little. It may be concluded that the removal of sulfur from DBT and hydrogenation take place on separate active sites, and that the spillover of the dissociated hydrogen species over the surface is essential to the hydrogenation pathway. Hydroxyl groups on H+-MCM-41 favors the spillover of the hydrogen species, enhancing the hydrogenation activity of its supported catalysts. On the other hand, Na+ cations on Si-MCM-41 may “trap” the spillover hydrogen species, lowering the hydrogenation activity of its supported catalysts. [Copyright &y& Elsevier]

A Pd/UiO-66 catalyst was synthesized with well-dispersed Pd nanoparticles. The obtained catalyst was tested in the hydrogenation of furfural to tetrahydrofurfuryl alcohol in various solvents, Water was found to be the most suitable solvent. Pd/UiO-66 exhibited much higher activity than Pd/SiO 2 and Pd/γ-Al 2 O 3 , completely converting furfural to tetrahydrofurfuryl alcohol with 100% selectivity under mild conditions. The hydrogenation of C O moiety in tetrahydrofurfural was rate-determining step. Static adsorption measurement indicated that the adsorption of furfural on UiO-66 was significantly stronger than that on SiO 2 or γ-Al 2 O 3 , suggesting that the adsorption play an important role in the gas-liquid-solid furfural hydrogenation reaction. Unlabelled Image • A Pd/UiO-66 catalyst was prepared with average Pd particle size of 2–3 nm. • 100% selectivity to tetrahydrofurfuryl alcohol was achieved by Pd/UiO-66. • Hydrogenation of C O moiety in tetrahydrofurfural was the rate-determining step. [ABSTRACT FROM AUTHOR]

ZSM-5-supported metal catalysts, including Fe/ZSM-5, Co/ZSM-5, Ni/ZSM-5, Cu/ZSM-5 and Mo/ZSM-5, were tested for the plasma-induced CO 2 hydrogenation in a dielectric-barrier discharge (DBD) plasma reactor. A significant synergy between DBD plasma and the catalyst was found. Without catalyst, CO 2 was converted solely to CO at a conversion level of 8.1% in the plasma. The supported metal catalysts enhanced CO 2 conversion and promoted the hydrocarbon formation. Co/ZSM-5 exhibited the best performance with a C 2 -C 4 selectivity of 13.7% at 45.0% CO 2 conversion. Powder XRD studies revealed that the stable active phase was Co metal particles in the Co/ZSM-5 catalyst. Unlabelled Image • There exists a significant synergy between plasma and catalysis in CO 2 hydrogenation. • Co/ZSM-5 catalyzes the formation of C 2 -C 4 hydrocarbons. • Cubic Co metal is the stable active phase for plasma-induced CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

• Cr-doped ZnS catalysts with various Cr/Zn ratios were prepared via co-impregnation method. • Cr doping led to enhanced decomposition of H 2 S in plasma. • The performance of the Cr-doped ZnS catalyst was stable in the runs. • The Cr 0.20 -ZnS catalyst showed the highest performance in H 2 S decomposition. A series of Al 2 O 3 supported Cr-doped ZnS semiconductor catalysts with various Cr/Zn molar ratios were prepared by co-impregnation method, and investigated in non-thermal plasma induced H 2 S decomposition. The as-synthesized catalysts were characterized using XRD, N 2 adsorption/desorption, UV-visible spectroscopy, TEM, Raman, ICP and XPS techniques. Cr-doped ZnS with different amount of Cr possessed the significantly enhanced catalytic performance, compared to undoped ZnS. Variations in catalytic activity are discussed in terms of modification on the chemical and physical properties of the Cr–doped ZnS catalysts. Among all the catalysts, the Cr 0.20 -ZnS catalyst showed the best catalytic behavior with full H 2 S conversion at lowest energy cost. Furthermore, the long-term study demonstrates that Cr–doped ZnS exhibits good stability in H 2 S decomposition. [ABSTRACT FROM AUTHOR]

The X-ray photoelectron spectroscopy characterization of a bulk WP hydrodesulfurization (HDS) catalyst demonstrated that the actual active surface phase of WP in the HDS of dibenzothiophene (DBT) is a sulfur-containing phase. This tungsten phosphosulfide phase formed faster than the molybdenum phosphosulfide phase, but possessed a lower sulfur content than the corresponding Ni 2 P and MoP phases. NH 3 was the dominant nitrogen-containing species detected in the WP catalyst after simultaneous HDS and hydrodenitrogenation reactions. NH 3 decreased the DBT conversion strongly but less than piperidine, indicating that not only N-containing compounds but also NH 3 inhibits the HDS activity of WP. [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly dispersed Ni 2 P catalyst was prepared from nickel phyllosilicate precursor. • Nickel phyllosilicate facilitated the formation of nanosized Ni 2 P particles. • (2 0 1) plane of Ni 2 P gave more coordinately-unsaturated active sites. • Ni 2 P/SiO 2 -DP exhibited high performance in hydrodesulfurization of 4,6-DMDBT. • Highly dispersed Ni 2 P catalysts were obtained on MCM-41, S-1, and TS-1. Highly dispersed Ni 2 P catalysts were prepared from nickel phyllosilicate precursor, which was generated on the support by the deposition–precipitation (DP) method. Si-containing materials, including SiO 2 , MCM-41, S-1, and TS-1, were used as the supports. The strong interaction between Ni and Si species in nickel phyllosilicate effectively suppressed the agglomeration of nickel species. Highly dispersed Ni 2 P catalyst (Ni 2 P/SiO 2 -DP) was obtained by subsequent temperature-programmed hydrogen reduction, and the size of Ni 2 P crystallites was smaller than that of Ni 2 P/SiO 2 -IM prepared from conventional impregnation precursor (7.7 nm vs 14.2 nm). HRTEM observation demonstrated that a large fraction of (2 0 1) planes were present in Ni 2 P/SiO 2 -DP whereas (1 1 1) planes were predominant in Ni 2 P/SiO 2 -IM. The strong metal-support interaction and the smaller particle size, along with the higher degree of coordinately unsaturated sites facilitated the hydrogen spillover and the hydrogenation activity. As a result, Ni 2 P/SiO 2 -DP exhibited significantly higher performance than Ni 2 P/SiO 2 -IM in hydrodesulfurization of 4,6-dimethyldibenzothiophene. Similarly, highly dispersed Ni 2 P catalysts supported on Si-containing molecular sieves (MCM-41, S-1, and TS-1) were obtained from the in situ generated nickel phyllosilicate as well. It seems that the strong interaction between Ni and Si species in nickel phyllosilicate precursor played a decisive role in the formation of highly dispersed and (2 0 1) plane-exposed Ni 2 P catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] • A highly dispersed Ni 3 P/HZSM-5 catalyst was prepared by modified electroless plating method. • Both deposition precipitation and electroless plating take place in aqueous solution, facilitating the formation of nano-sized Ni 3 P. • Bifunctional Ni 3 P/HZSM-5 exhibited high performance in hydrodeoxygenation of phenolic compounds. A highly dispersed Ni 3 P/HZSM-5 catalyst was prepared by deposition-precipitation of Ni species followed by electroless plating and thermal treatment, and characterized by means of XRD, ICP, N 2 physical adsorption, TEM, XPS, NH 3 -TPD, and CO chemisorption. Electroless plating reaction takes place in an aqueous solution under mild conditions, facilitating the high dispersion of the formed Ni 3 P particles. XRD measurements illustrated the lamellar nickel phyllosilicate was produced at the first step of deposition-precipitation, amorphous Ni-P was formed in the subsequent electroless plating, and highly dispersed Ni 3 P crystallites were generated in thermal treatment. TEM observation demonstrated that the average particle size of Ni 3 P crystallites in the prepared Ni 3 P/HZSM-5 catalyst was 4.3 nm. Bifunctional Ni 3 P/HZSM-5 was investigated in hydrodeoxygenation (HDO) of phenolic compounds, including phenol, m-cresol, and guaiacol. Ni 3 P/HZSM-5 exhibited high catalytic performance in HDO with enhanced hydrogenation and dehydration pathway. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amino groups showed significant different effects on different reaction pathways. • The dibenzothiophene conversion decreased slightly with the content of amino groups. • A correlation was observed between CO-IR results and the catalyst performance. • The amino groups may affect the adsorption of reacting molecules on Pd particles. • The hydrodesulfurization reactions followed a Langmuir-Hinshelwood kinetics. The hydrodesulfurization (HDS) of dibenzothiophene (DBT) was studied over a series of Pd catalysts supported on Zr-based metal-organic frameworks, UiO-66 and its amino-functionalized analogues (UiO-66-xNH 2 , where x represents the molar ratio of 2-amino-1,4-benzenedicarboxylic acid/1,4-benzenedicarboxylic acid) to gain an insight into metal-support interactions. Pd/UiO-66 behaved better than a Pd/γ-Al 2 O 3 catalyst and a Pd/MCM-41 catalyst. The presence of amino groups showed minor negative influence on the conversion of DBT but significantly affected the activities and selectivities of different reaction pathways. With the increase in the content of amino groups, the direct desulfurization (DDS) pathway activity of the Pd/UiO-66-xNH 2 catalysts increased, while their hydrogenation pathway activity decreased. This provides an approach for the regulation of the pathway selectivities of Pd HDS catalysts. Based on kinetic analysis and characterization results, we propose that the amino groups affect the HDS performance of Pd/UiO-66 mainly by affecting the adsorption of reacting molecules on metal particles. [ABSTRACT FROM AUTHOR]

1,2,3,4-Tetrahydro-4,6-dimethyldibenzothiophene was prepared by coupling 2-bromo-3-methylcyclohexanone with 2-methylbenzenethiol and annulating the product with the aid of polyphosphoric acid. A mixture of 1,2,3,4-tetrahydro-4,6-dimethyldibenzothiophene and 4,6-dimethyldibenzothiophene was prepared by coupling 2-bromo-3-methylcyclohex-2-en-1-one with 2-methylbenzenethiol and annulating the product with the aid of polyphosphoric acid. 2-Bromo-3-methylcyclohexanone was synthesized by conjugate addition of Me3Al to 2-bromocyclohex-2-en-1-one with CuBr as catalyst and 2-bromo-3-methylcyclohex-2-en-1-one by brominationelimination of 3-methylcyclohex-2-en-1-one. 1,2,3,4,4a,9b-Hexahydro-4,6-dimethyldibenzothiophene was prepared by reduction of 1,2,3,4-tetrahydro-4,6-dimethyldibenzothiophene with Zn and CF3COOH. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bifunctional Ni 3 P/γ-Al 2 O 3 was prepared by an electroless plating method. • A deposition–precipitation method was adapted to improve the dispersion. • Ultrafine Ni 3 P particles (~3.8 nm) were dispersed homogeneously on γ-Al 2 O 3. • Ni 3 P/γ-Al 2 O 3 exhibited high performance and stability in phenol hydrodeoxygenation. A bifunctional Ni 3 P/γ-Al 2 O 3 catalyst was prepared by an electroless plating method and characterized by XRD, XPS, N 2 adsorption–desorption, ICP, TEM, CO chemisorption, NH 3 TPD, and Py-FTIR. To improve the dispersion of Ni 3 P on γ-Al 2 O 3 , highly dispersed nickel aluminum oxide hydrate was deposited on γ-Al 2 O 3 by a deposition–precipitation procedure. The resulting Ni 3 P nanoparticles (~3.8 nm) were homogeneously dispersed on γ-Al 2 O 3. The Ni 3 P/γ-Al 2 O 3 catalyst exhibited high performance in the hydrodeoxygenation of phenol, in which both hydrogenation and dehydration were involved. The Ni 3 P/γ-Al 2 O 3 was remarkably stable both in catalytic performance and in structure during a 100-h run. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bifunctional Ni 3 P/γ-Al 2 O 3 was prepared by an electroless plating method. • A deposition–precipitation method was adapted to improve the dispersion. • Ultrafine Ni 3 P particles (~3.8 nm) were dispersed homogeneously on γ-Al 2 O 3. • Ni 3 P/γ-Al 2 O 3 exhibited high performance and stability in phenol hydrodeoxygenation. A bifunctional Ni 3 P/γ-Al 2 O 3 catalyst was prepared by an electroless plating method and characterized by XRD, XPS, N 2 adsorption–desorption, ICP, TEM, CO chemisorption, NH 3 TPD, and Py-FTIR. To improve the dispersion of Ni 3 P on γ-Al 2 O 3 , highly dispersed nickel aluminum oxide hydrate was deposited on γ-Al 2 O 3 by a deposition–precipitation procedure. The resulting Ni 3 P nanoparticles (~3.8 nm) were homogeneously dispersed on γ-Al 2 O 3. The Ni 3 P/γ-Al 2 O 3 catalyst exhibited high performance in the hydrodeoxygenation of phenol, in which both hydrogenation and dehydration were involved. The Ni 3 P/γ-Al 2 O 3 was remarkably stable both in catalytic performance and in structure during a 100-h run. [ABSTRACT FROM AUTHOR]

• CoP and Co 2 P were prepared with stoichiometric P/Co ratios. • Hydrodesulfurization (HDS) reactions over CoP and Co 2 P followed different kinetics. • CoP was much more active and more nitrogen-tolerant than Co 2 P. • The network of the HDS of dibenzothiophene over CoP and Co 2 P was determined. • The cobalt phosphosulfide phases were formed in the HDS reactions. CoP and Co 2 P were prepared by temperature-programmed reduction of the mixtures of Co(OH) 2 and H 3 PO 3 with stoichiometric P/Co ratios, but their surfaces were still enriched in phosphorus. Based on the product distributions of the hydrodesulfurization (HDS) of dibenzothiophene (DBT), 1,2,3,4-tetrahydro-dibenzothiophene (TH-DBT), and 1,2,3,4,4a,9b-hexahydro-dibenzothiophene (HH-DBT), a reaction network of DBT HDS was proposed and the mechanisms of the cleavage of different C S bonds in DBT and its hydrogenated intermediates were discussed. CoP was much more active and more nitrogen-tolerant than Co 2 P, which make it a promising HDS catalyst. The HDS reactions over CoP and Co 2 P followed a pseudo-first-order kinetics and a pseudo-zero-order kinetics, respectively. Piperidine strongly inhibited the hydrogenation/dehydrogenation reactions and the direct desulfurization of DBT, but its inhibition on the desulfurization of TH-DBT and HH-DBT were less pronounced. The active surfaces of CoP and Co 2 P in HDS reactions can be cobalt phosphosulfide phases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon confined Cu-Pd nanoalloy catalysts are successfully synthesized through an eco-friendly, facile and efficient approach. • Carbon encapsulation strategy efficiently improves the ethylene selectivity and stability for selective hydrogenation of acetylene. • Carbon layer acts as "cages" for confining the growth of the carbon chain to oligomer during the acetylene hydrogenation. • This synthesis strategy can be extended to other carbon confined Cu and Ag-based bimetal catalysts. A catalyst with high selectivity for acetylene selective hydrogenation is highly desirable, yet ideal selectivity often comes at the price of activity loss. Here, a carbon confined Cu 15 Pd catalyst (Cu 15 Pd@C) was fabricated through an eco-friendly and efficient approach, which improves ethylene selectivity while at the same time, maintains high activity. Under optimized conditions, acetylene conversion of 100% and ethylene selectivity of 91% were simultaneously achieved. Comprehensive characterization and DFT reveal that the carbon layer not only promotes the formation of smaller nanoparticles, but effectively inhibits the production of green oil, which is associated to the confined spatial microenvironment by the carbon layer, posing steric hindrance to chain growth from acetylene coupling. A series of carbon confined Cu and Ag-based bimetal catalysts were fabricated through the same method, proving the facilitation of carbon layer on such selective hydrogenation universal, and also showed great potential of our method and catalysts in practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu x C-Cu was obtained by reacting Cu(OH) 2 with C 2 H 2 /Ar and subsequent H 2 reduction. • Cu x C-Cu showed significantly higher hydrogenation activity than Cu metal. • The addition of ZnO led to improved dispersion and catalytic performance. • Cu x C-Cu-ZnO composite catalyst performed well in glycerol hydrogenolysis. The hydrogenolysis of renewable glycerol towards 1,2-propanediol (abbreviate as 1,2-PDO) has been a promising approach. In this work, high-performance catalysts containing copper carbide (Cu x C) were prepared by the following procedure: (1) synthesis of Cu(OH) 2 -Zn(OH) 2 mixture via a microchannel reaction system, (2) thermal treatment at 100 °C in 0.50 vol% C 2 H 2 /Ar gas, and (3) reduction at 300 °C under H 2 atmosphere. The continuous synthesis of Cu(OH) 2 -Zn(OH) 2 mixture in a microchannel reaction system yielded highly dispersed precursors, and the addition of ZnO led to improved dispersion of copper species with enhanced acidity. The new crystal phase, copper carbide (Cu x C), was generated through reacting Cu(OH) 2 particles with C 2 H 2 /Ar and subsequent hydrogen reduction. Cu x C exhibited significantly higher hydrogenation activity than Cu metal, and contributed to enhanced catalytic activity for continuous glycerol hydrogenolysis in the fixed-bed reactor. Copper carbide composite catalyst (Cu/Zn = 8) afforded 100 % glycerol conversion and high selectivity (92.3 %) towards 1,2-PDO at 240 °C, 2.0 MPa and WHSV 3 h−1. [ABSTRACT FROM AUTHOR]