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Photocatalytic conversion of renewable biomass‐derived aldehydes into high‐valued chemicals is a promising path to meet the growing demand for clean energy and chemical resources. However, the approach still faces challenges, such as limited reaction types and low utilization rates due to the complex functional groups and involved polytropic reaction. In the present work, we developed a catalyst of Pt nanoparticles (Pt NPs) supported on a NiO–In2O3 bimetallic oxide (denoted as Pt/NiInOx) for photocatalytic hydrogenation of furfural (FAL) to furfural alcohol (FOL). Owing to the excellent band structure and efficient internal charge transfer on the p–n heterojunction in the catalyst, the highest 99.9% yield to FOL was obtained over the Pt/NiInOx under a light‐emitting diode (LED) light at low temperatures as 273 K. The combination of ·H dissociated from H2 and oxygen vacancy work synergically to adsorb, activate, and converse C=O to the C–O group. The photocatalytic system presents a highly efficient approach for the rapid hydrogenation of biomass‐based aldehydes under a low LED light radiation intensity at a low temperature. The work is expected to serve as an important reference in constructing bimetallic oxide‐supported active metals, enabling efficient separation of photogenerated electrons and holes, and offering oxygen vacancies in various photocatalytic reactions. [ABSTRACT FROM AUTHOR]

In this work, a fast and self-propagated carbonization (SPC) method to prepare phosphorus-doped carbon (PDC) and hybrid materials is proposed. PdZr/PDC prepared by the SPC method has good catalytic performance for both partial oxidation of benzyl alcohol to benzaldehyde and partial hydrogenation of phenol to cyclohexanone. The method has some obvious advantages, such as being simple and clean, and can be used easily for the large-scale preparation of the materials. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction is a highly vital process for converting CO2 into valuable chemicals. However, the reaction always proceeds less efficaciously at low temperature. A combination of optical and thermal conditions is one of the feasible approaches to achieve the reaction with high efficiency and has gained much attention recently. In the present work, we prepared several Co–Cu–Mn trimetallic catalysts via a simple co-precipitation method, which were used in catalyzing photothermal CO2 reduction to hydrocarbons. The metal composition and reduction temperature of the catalysts had important effects on their structural and photoelectrical characteristics and adsorption behaviors, further resulting in diverse catalytic performances. Among the prepared trimetallic catalysts, Co7Cu1Mn1Ox(200), with a Co/Cu/Mn molar ratio of 7/1/1 and reduced at 200 °C in H2 for 2 h, could produce CH4 with an activity of 14.5 mmol gcat−1 h−1 in 10% CO2/30% H2/60% N2, and CH4 and C2+ hydrocarbons with the activities of 15.9 and 7.5 mmol gcat−1 h−1 in 25% CO2/75% H2, respectively. The present strategy for constructing trimetallic oxide catalysts for the photothermal reaction not only provides a highly active catalyst for CO2 utilization, but also offers a potential possibility for reducing the high temperature of conventional thermal reactions. [ABSTRACT FROM AUTHOR]

• A CoO/Co/TiO 2 was prepared and used in photothermal CO 2 hydrogenation to CH 3 OH. • The CoO semiconductor film was formed with a thickness of 5–6 nm from air oxidation. • Co0 species are stable at the interface of Co NPs with TiO 2. • A Z scheme mechanism was proposed for CH 3 OH formation with 39.6 μmol g cat –1 h–1. Catalytic conversion of CO 2 into methanol is of particular interest as it does not only provide valuable methanol, but also utilize the waste CO 2. In the present work, a CoO/Co/TiO 2 catalyst was developed and utilized in catalyzing CO 2 to methanol under photothermal conditions. From the results of characterization, the supported Co nanoparticles (NPs) were composed of Co0 in the bulk, CoO film formed from air oxidation on the surface, and Co0 at Co NPs-TiO 2 interfaces. This structure provided the possibility for a Z scheme photothermal catalytic system, which revealed a high activity for methanol formation in aqueous media under atmosphere pressure. It was proposed that the light excited electrons from the valence band (VB) of TiO 2 , and the excited electrons could enhance the Co0 catalytic activity under thermal conditions. The present approach will offer a new strategy to design Co based Z scheme catalysts and further improve the conversion efficiency from CO 2 to fuels. [ABSTRACT FROM AUTHOR]

[Display omitted] • Precious metal-free Co 3 Cu 1 O x catalyst is active for the selective hydrogenation of quinolines at low temperature (60 °C). • The high activity for the Co 3 Cu 1 O x catalyst is related to the high H 2 absorption ability. • The gram-scale experiment of hydrogenation of quinoline gave 92% yield to 1,2,3,4-tetrahydroquinoline. • The easily prepared and magnetic Co 3 Cu 1 O x catalyst could be reused at least five times without obvious loss in activity. Quinoline derivatives are widely exist in the environment, and mainly separated from the coal tar pitch fraction. Hydrogenation of these compounds to 1,2,3,4-tetrahydroquinolines, an important class of natural products and medicinal agents, is a significant transformation of waste to valuable chemicals. In the present work, we developed a cheap and highly efficient Co 3 Cu 1 O x bimetallic catalyst and used it for the hydrogenation of quinolines at a temperature down to 60 °C. The introduction of Cu into Co catalyst changed the physical and chemical features of Co catalyst, which was characterized by Raman spectra, N 2 -adsorption/desorption isotherms, H 2 -TPR and H 2 -TPD tests. The recycling experiments indicated the catalyst was stable and possessed good reusability. Importantly, the gram-scale experiment provided a high yield (92%) to the target product, demonstrating that the catalytic system has a potential practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co 3 O 4 /AlN and its reduced form Co/AlN catalysts were prepared. • Co 3 O 4 /AlN can efficiently catalyze the oxidative dehydrogenation of N -heterocycles. • Co/AlN can achieve hydrogenation of N -heterocycles. • A strong interaction between Co species and AlN support existed. N -heterocycles with quinoline and tetrahydroquinoline structures are highly important in pharmaceutical and chemical industries, and their highly efficient mutual transformations are vital but still challenging. In the present work, AlN supported redox cobalt catalysts (Co 3 O 4 /AlN and Co/AlN) were prepared, which could achieve the reversible aerobic oxidative dehydrogenation/hydrogenation of N -heterocycles with good performances. The catalytic performances were stem from the strong interaction between Co species with AlN support, which were confirmed by the characterizations of Raman, XPS, UV–vis DRS, and H 2 -TPR etc. Both of the catalysts showed good stabilities and reusabilities for the titled reactions. Besides, the gram-scale experiments achieved with good yields to corresponding products, revealing the present protocol possesses great potential applications in industry. The strategy of using redox Co-based catalyst not only provides a potential catalyst for the reversible hydrogenation/oxidative dehydrogenation reactions but also replenishes methods for constructing of other redox catalyst, especially with AlN as a carrier. [ABSTRACT FROM AUTHOR]

Exploring loaded noble metal catalysts for hydrogenation of phenol to cyclohexanone under a mild reaction condition of atmospheric and low temperature is desirable but challenging. In the present work, Pd supported over acetylene black catalyst (Pd/ACET) was prepared by a simple impregnation method using industrial waste acetylene black as a carbon carrier. The catalyst is able to hydrogenate phenol to cyclohexanone with a high conversion of 97.3 % and a high selectivity of 99.9 %. Different metal loadings were found to have a large effect on the bonding state and functional structure of the acetylene black surface. A higher Pd0/Pd2+ ratio in the catalyst could produce a better catalytic performance on the phenol hydrogenation. The kinetic process of phenol hydrogenation was investigated to kinetically reveal the nature of high selectivity. [Display omitted] • Pd supported on acetylene black (Pd/ACET) was easily prepared by impregnation method. • The Pd/ACET performs high efficiency for selective hydrogenation of phenolin water solvent. • The catalyst has good stability during the reaction. • The high selectivity was revealed by the kinetic study and the surface functional groups. [ABSTRACT FROM AUTHOR]

• A series of FeNiCu/MCM-41 catalysts were successfully synthesized by the impregnation method. • A desired efficient and selective hydrogenation of quinolines was achieved at low temperature and in solvent-free system. • 58% Fe 4 Ni 6 Cu 5 /MCM-41 catalyst achieved 97.5% conversion and exceeding 98% selectivity to tetrahydroquinoline under mild conditions. • Possible catalytic mechanism of the synergism of Fe-Ni and Ni-Cu alloys was proposed. The development of non-precious metal catalysts in heterogeneous catalytic processes is of great importance to the hydrogenation of quinolines for both theoretical and industrial applications. Herein, an effective non-precious metal catalyst, 58% Fe 4 Ni 6 Cu 5 /MCM-41, was developed to catalyze the hydrogenation of quinolines under the green and mild conditions, which can achieve 97.5% conversion and exceeding 98% selectivity to tetrahydroquinoline in solvent-free at low temperature of 50 °C. Moreover, the acceptable results of the reusability and gram scale-up experiments proved an industrial application potential of the as-prepared catalyst. Meanwhile, in cyclohexane system, 58% Fe 4 Ni 6 Cu 5 /MCM-41 catalyst can further realize a higher activity of the hydrogenation at a lower temperature of 40 °C, achieving 98.2% conversion and 98% selectivity to tetrahydroquinoline. The existence of Fe-Ni and Ni-Cu alloys in Fe 4 Ni 6 Cu 5 /MCM-41 catalyst was demonstrated by TEM, XRD, XPS, H 2 -TPD, and Raman spectroscopy. And, Fe-Ni and Ni-Cu alloys can be well dispersed onto MCM-41 molecular sieves. For Fe 4 Ni 6 Cu 5 /MCM-41 catalyst, quinoline molecules can be adsorbed by Fe3+ species on the surface of Fe-Ni alloy through the coordination, while hydrogen molecules can be adsorbed and activated by Ni-Cu alloy. Under the synergism of Fe-Ni and Ni-Cu alloys, the highly effective and selective hydrogenation of quinolines was achieved at low temperature and in solvent-free system. The present approach offers a prospective idea for building non-precious metal catalysts to realize the effective hydrogenation of N-heterocyclic compounds under mild conditions. [Display omitted] [ABSTRACT FROM AUTHOR]