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As Sweden takes its first steps towards a hydrogen-based economy, a strategic approach to infrastructure development for both storage and delivery becomes necessary. Although compressed hydrogen is currently the state-of-the-art, its low volumetric density and associated high capital costs pose challenges to widespread societal deployment of hydrogen. In order to avoid technological lock-in, alternatives storage technologies including chemical hydrides, e.g. methanol, ammonia, methane and LOHC, must also be explored. These alternatives offer higher hydrogen densities, safer handling, and compatibility with existing infrastructure. However, each hydride has unique chemical and physical properties, requires distinct feedstock and conversion processes, and interacts with the energy system in different ways, all of which influences their suitability for various applications. Therefore, a comprehensive evaluation of these alternative hydrogen storage technologies, as carried out in this article, is vital to allow for informed investment decisions and pave the way towards a successful and sustainable hydrogen economy. • Chemical hydrides have emerged as promising hydrogen storage alternatives. • Chemical hydrides facilitate cheaper global hydrogen trade. • Sweden's biogenic CO 2 emissions promote storage in methanol and methane. • Optimal storage choice depends on specific applications and their energy systems. • Chemical hydrides have high technological maturity. [ABSTRACT FROM AUTHOR]

Ni/TiO2 catalysts are efficient and cost‐effective for photothermal CO2 hydrogenation. However, the achieved CO/CH4 ratio strongly depends on the specific characteristics of these catalysts. To further ascertain the role of metal dispersion and photoactivation on selectivity, in this work we investigate the impact of Ni loading over high surface area anatase on the photothermal performance. Catalysts with 3 and 10 wt. % of Ni prepared by incipient wetness impregnation show initial good dispersion of the metal, although after activation in H2 metallic Ni nanoparticles are observed for 10 %Ni/TiO2. This last catalyst demonstrates superior CO2 hydrogenation activity at high temperature, but below 200 °C it is overpassed by the catalyst with 3 wt % Ni/TiO2. The selectivity varies remarkably with Ni loadings. Thus, at 350 °C about 93 % of methane is obtained over 10 wt.% Ni/TiO2, while 3 %Ni/TiO2 yields about 97 % of CO. Low‐intensity UV irradiation enhances performance, particularly at temperatures below 200 °C, where an increment in the production of methane of up to 75 % is observed for 3 wt.% Ni/TiO2 at 200 °C. These results highlight the influence of metal dispersion, along with irradiation on modulating the selectivity of the photothermal CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

The demand for diesel has been decreasing year on year in recent years, LCO (light cycle oil of FCC unit), as the main component of diesel pools, has encountered the problem of overcapacity. The key to solving the overcapacity of LCO is to make reasonable use of the rich bicyclic aromatic hydrocarbon components in LCO and explore new technologies for the conversion of suitable aromatics to aromatics. Starting from the structural composition of LCO, this paper systematically summarizes the recent development status of six technologies for producing various high-value products using LCO as raw material. Among them, LTAG technology has a high yield of high octane gasoline, but reducing reaction hydrogen consumption is a major challenge; LCO preparation of BTX is an effective method for oil conversion, but high hydrogen consumption low selectivity of BTX lead to poor tech no-economics; the preparation of COP- NA resin by LCO can produce high-performance B resin with by-production of high cetane diesel components. However, the curing and crosslinking agents used still have the problem of being expensive. Finally, summary and outlook were made on the current technical issues of LCO production of high-value products. [ABSTRACT FROM AUTHOR]

Water injection for absorbing corrosive gases NH3, HCl and H2S is a widely employed method to mitigate the risk of ammonium salt corrosion in the hydrogenation units. To ensure the efficient prevention of ammonium salt corrosion, a numerical model integrating the hydrodynamics of gas–liquid and the reaction of interphase mass transfer was built based on Euler–Lagrange method in this work. The flow and mass transfer characteristics of complex multi-component system in water injection pipeline were investigated, and the correlation between process operating conditions and gas removal performance was analyzed. The results reveal that the removal efficiencies of corrosive gases in pipeline are influenced by the characteristics of gas–liquid flow and mass transfer, with HCl showing higher removal efficiency compared to NH3 and H2S. Furthermore, the increasing flow rate of water injection, the reducing corrosive medium content and the decreasing droplet diameter have a positive impact on the removal efficiencies of corrosive gases, while the impact of gas-flow velocity on the removal efficiencies of corrosive gases primarily depends on the residence time of droplets. These results have important theoretical value and engineering guiding significance for intensifying the process of water injection in hydrogenation units. [ABSTRACT FROM AUTHOR]

Objective In the sulfuric acid alkylation unit, the main causes and solutions to the deactivation of the hydrogenation catalyst were found by analyzing the running status of the selective hydrogenation reactor of 1,3-butadiene. Methods By analyzing the feedstock properties before and after catalyst deactivation, the effect of feedstock properties changes on the 1,3-butadiene removal rate was investigated. Results For the selective hydrogenation of the 1,3-butadiene catalyst, a high level of pH, caustic sodium and total sulfur contents in feedstock will inhibit the active centers of the catalyst. Conclusion The harmful impurities in feedstock were removed by optimizing operation. Additionally, the deactivated catalysts were re-activated by on-line treatment with pure hydrogen, the catalyst activity was significantly restored and maintained long-cycle running after re-starting up. [ABSTRACT FROM AUTHOR]

In this work, a series of nickel-containing samples of carbon xerogels (Ni@CX) were synthesized by introducing nickel acetate into a solution of precursors (resorcinol and formaldehyde), joint polycondensation, and subsequent pyrolysis in an atmosphere of argon. The samples were tested in the selective hydrogenation reaction of 1,3-butadiene. It was shown that catalysts prepared without the addition of complexing agents contained nickel nanoparticles (4–7 nm) stabilized in a carbon matrix. The Ni@CX catalyst made it possible to achieve a selectivity of 93% for butenes at a conversion of 94% and a temperature of 200°C, while the selectivity for the formation of butenes in the presence of an impregnated reference sample was lower than 1%, although it provided a conversion of 100% already at 75°C. It was supposed that the selectivity of catalysts prepared by the joint synthesis increased due to the blockage of nonselective catalytic sites by carbon of the support. [ABSTRACT FROM AUTHOR]

Hydrogenation of CO2 represents a promising pathway for converting it into valuable hydrocarbons and clean fuels like dimethyl ether (DME). Despite significant research, several challenges persist, including a limited understanding of reaction mechanisms, thermodynamics, the necessity for catalyst design to enhance DME selectivity, and issues related to catalyst deactivation. The paper provides a comprehensive overview of recent studies from 2012 to 2023, covering various aspects of CO2 hydrogenation to methanol and DME. This review primarily focuses on advancing the development of efficient, selective, and stable innovative catalysts for this purpose. Recent investigations that have extensively explored heterogeneous catalysts for CO2 hydrogenation were summarized. A notable focus is on Cu-based catalysts modified with promoters such as Zn, Zr, Fe, etc. Additionally, this context delves into thermodynamic considerations, the impact of reaction variables, reaction mechanisms, reactor configurations, and recent technological advancements, such as 3D-printed catalysts. Furthermore, the paper examines the influence of different parameters on catalyst deactivation. The review offers insights into direct CO2 hydrogenation to DME and proposes paths for future investigation, aiming to address current challenges and advance the field. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading (1 mo%) of copper N‐heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen. A wide range of nitroarenes, featuring diverse functional groups, were selectively transformed into their corresponding primary aromatic amines with high yields. This process can be readily scaled up and exhibits compatibility with various sensitive functional groups, including halogen, trifluoromethyl, aminomethyl, alkenyl, cyano, ester, amide, and hydroxyl. Notably, this catalytic methodology finds application in the synthesis of essential drug compounds. Mechanistic investigations suggest that the in‐situ‐generated Cu‐H species may serve as active intermediates, with reduction pathways involving species such as azobenzene, 1,2‐diphenylhydrazine, nitrosobenzene, and N‐phenylhydroxylamine. [ABSTRACT FROM AUTHOR]

Despite immense interest for years in Heusler alloys as magnetoelastic materials, their application in heterogeneous catalysis has only recently been explored. We report the development of highly active, robust and magnetically separable Ni2MnAl Heusler alloy nanoparticles as a heterogeneous catalyst for hydrogenation of aliphatic and aromatic nitro compounds to the corresponding amines. The easily synthesizable Ni2MnAl nanoparticles are thermally and chemically robust and exhibited excellent chemoselectivity in the hydrogenation of a range of aliphatic and aromatic nitroarenes, including those bearing functional groups sensitive to reduction, such as alkene, bromo, iodo, carbonyl and cyano, yielding the respective functionalized amines in good yields. Moreover, this solid catalyst is magnetically separable from the reaction mixture and could be recycled and reused at least 10 times without any loss in catalytic activity. The mechanism of the Ni2MnAl Heusler alloy nanoparticles catalyzed nitro reduction was studied by various spectroscopy, control experiments and kinetics. Our work opens a new avenue of developing heterogeneous earth‐abundant metal catalysis for economic and environment‐friendly synthesis of fine chemicals owing to straightforward synthesis and tunable composition of Heusler alloy nanoparticles from base‐metal precursors and their diverse structure and properties in conjunction with their thermal and chemical stability, excellent chemoselectivity, magnetic separability and recyclability. [ABSTRACT FROM AUTHOR]

Since catalytic chemoselective reduction of corresponding nitroarenes is a significant route to produce functionalized anilines, developing inexpensive and highly active catalyst is imperia. Herein, the Co‐Ce‐H2salen‐hmta composite was first prepared by grinded completely the mixture of Co‐H2Salen and hexamethylenetetramine (hmta) in 1:1 mol ratio in a mortar. The 3d–4f hetero‐metal Co‐Ce‐H2salen coordination polymer acted as a support precursor and hmta provided the nitrogen source. Then, a target catalyst of Co/NC‐CeO2‐hmta were afforded by pyrolysis of Co‐Ce‐H2salen‐hmta composite at 800°C in the presence of argon atmosphere. When the target catalyst of Co/NC‐CeO2‐hmta and reference catalysts were applied for the hydrogenation of nitroarenes under N2H4, the target catalyst of Co/NC‐CeO2‐hmta exhibited better performance than reference catalysts in terms of conversion, yield, selectivity, and recyclability. Spectral analysis suggested that the high catalytic performance of a target catalyst of Co/NC‐CeO2‐hmta were attributed to highly dispersed metallic Co0, rich oxygen vacancies, and nitrogen‐doped carbon matrix. [ABSTRACT FROM AUTHOR]

The bulk and surface properties of materials based on nickel and aluminum oxides and hydroxides, as such or after reduction processes, are reviewed and discussed critically. The actual and potential industrial applications of these materials, both in reducing conditions and in oxidizing conditions, are summarized. Mechanisms for reactant molecule activation are also discussed. [ABSTRACT FROM AUTHOR]

Pd/C catalysts play a pivotal role in contemporary chemical industries due to their exceptional performance in diverse hydrogenation processes and organic reactions. Over the past century, researchers have extensively explored the factors influencing Pd/C catalyst performance, particularly emphasizing the impact of oxygen-containing groups through oxidation or reduction modifications. However, most studies use respective Pd/C catalysts to analyze the catalytic reactions of one or a class of chemical bonds (polar or non-polar). This study investigates alterations in Pd/C catalysts during temperature-programmed reduction (TPR) and evaluates the hydrogenation activity of unsaturated polar bonds (C=O, acetophenone) and non-polar bonds (C≡C, phenylacetylene) in Pd/C catalysts. The experimental results indicate that the reduction of Pd/C decreases the content of oxygen-containing groups, reducing hydrogenation activity for acetophenone but increasing it for phenylacetylene. This research highlights the preference of regular Pd surfaces for non-polar bond reactions and the role of Pd/oxide sites in facilitating polar bond hydrogenation. These discoveries offer essential insights into how oxygen-containing groups influence catalytic performance and allow us to propose potential avenues for enhancing the design and production of Pd/C catalysis. [ABSTRACT FROM AUTHOR]

Furfural is a well-recognized biomass platform. Hydrogenation and reductive amination of furfural are two principal routes in the valorization of this compound. In both reactions, the presence of reducible species (SMSI effect) and acid sites could favor the selectivity toward some interesting products. Both conditions could be obtained using metal particles supported on reducible mixed oxides. In this work, we investigate the use of Pt/Nb2O5-Al2O3 catalysts for the hydrogenation and reductive amination of furfural at distinct Nb2O5 contents. A decaniobate salt was used as a precursor of Nb2O5. The solids were reduced at 500 °C to assure the migration of reducible NbOx species. The solids were characterized by XRD, Raman spectroscopy, HR-TEM, N2-physisorption, NH3-TPD and Pyr-DRIFTS. The results showed that higher Nb2O5 loadings led to a lower distribution of Al2O3 and Pt, favoring the catalysts' acidity. This fact implies that large particle size and the presence of Nb2O5 islands favor the formation of furfuryl alcohol but have a detrimental effect on the amine formation in the reductive amination of furfural. [ABSTRACT FROM AUTHOR]

TiO2-supported Pd NPs-based materials were prepared following two distinct approaches: For the first set of materials 1–8, modification of the TiO2 support was performed prior to Pd NPs deposition, while the second set (9–15) was synthesized by deposition of modifiers over pre-synthesized Pd-PPh3/TiO2. These catalysts were applied in the hydrogenation of CO2 to formate, and their performance was compared with that of the unmodified Pd-PPh3/TiO2. Modification of the TiO2 support by organosilanes provided a beneficial effect in catalysis compared with the catalyst containing unmodified TiO2 or TiO2 modified by organophosphonic acids. In contrast, in most cases, the deposition of modifiers over previously synthesized Pd NPs supported on TiO2 was not beneficial to the activity of the catalyst. Interestingly, upon recycling, the first set of catalysts suffered a rapid decrease in activity, while the anchoring of modifiers over previously formed Pd NPs showed an improved stability (TON > 500 after the third recycling). [ABSTRACT FROM AUTHOR]

Chalcones are a class of naturally occurring flavonoid compounds associated to a variety of biological and pharmacological properties. Several reviews have been published describing the synthesis and biological properties of a vast array of analogues. However, overviews on the reactivity of chalcones has only been explored in a few accounts. To fill this gap, a systematic survey on the most recent developments in the transition metal‐catalyzed transformation of chalcones was performed. The chemistry of copper, palladium, zinc, iron, manganese, nickel, ruthenium, cobalt, rhodium, iridium, silver, indium, gold, titanium, platinum, among others, as versatile catalysts will be highlighted, covering the literature from year 2000 to 2023, in more than 380 publications. [ABSTRACT FROM AUTHOR]

A set of Pd-containing composites was prepared by the deposition of Pd on the following carriers: polyaniline (PANI); PANI doped by H2SO4; Norit GSX activated carbon or Aerosil (SiO2) coated by PANI or by H2SO4-doped PANI; PANI after thermal treatment at 300 °C in an atmosphere of H2. One sample was also prepared by the in situ polymerization of aniline in the presence of Pd2+· The decomposition of Pd was carried out via deposition from the solutions of Pd2+ salts or decomposition of Pd0 complex Pd2(dba)3, where dba is dibenzylideneacetone. The composites were studied by powder X-ray diffraction, transmission electron microscopy, IR and Raman spectroscopy. The hydrogenation of quinoline in the presence of composites was carried out; the catalytic performance of the composites was evaluated by the yield of 1,2,3,4-tetrahydroquinoline. It was found that the doping of PANI by H2SO4, inclusion of Norit GSX activated carbon as a component of the carrier or thermal treatment of PANI prior to the deposition of Pd led to significant increase in the catalytic performance of the composites in the hydrogenation of quinoline. [ABSTRACT FROM AUTHOR]

It is highly desired that performance of Pd catalysts is improved by the design and preparation of homogeneously dispersed and stablized in many industrial catalytic processes and still a big challenge. Herein, small-sized Pd over Al2O3-flower (f-Al2O3) via compartmentalization strategy is successfully prepared. Ultrafine Pd phases are highly dispersed and thermally stabilized by flower-liked architectures, which not only efficiently suppress Pd aggregation at reaction conditions, but also promote mass transport and reactants access to active sites easily. The catalysts exhibit a stable acetylene conversion of 93% with ethylene selectivity of 94% within a single running of 60 days (60 ℃, GHSV 4500 h−1) without introducing any promoter, and high TOF value (0.4 S−1) are achieved as well. This work provides a facile strategy of improving the activity and thermal stability of Al2O3-supported nano-catalysts in industrial application. [ABSTRACT FROM AUTHOR]

An eggshell-type structure Pd–Ni bimetallic catalysts with different ratios of Pd–Ni (Pd–Ni/Al2O3) were prepared by the deposition–precipitation method using spherical Al2O3 as a support and were first applied to the catalyst 2-methylfuran (2-MF) hydrogenation reaction. The effect of Ni loading on Pd–Ni bimetallic interactions was explored in the 2-MF hydrogenation reaction. By introducing the Ni component, both the use of the noble metal Pd is reduced and the activity of the catalyst is improved. The activity curves results was shown that the Pd–Ni/Al2O3 catalyst had the highest activity and stability when the ratio of the substance amounts of the Pd and Ni components was regulated to be 1.5. Reducing the reaction temperature and pressure, with a conversion and selectivity of 99.6% and 99.5%, respectively. The catalyst is highly stable and active due to the interaction of the metal carriers to produce an active electron-deficient palladium species (Pdn+), with only a 1% decrease in conversion after 7 cycles and recovery of activity after calcination. The unique eggshell-type structure allows for selective deposition of the active components Pd and Ni in the outer regions of the spheres, enabling efficient use of the active components at high air velocities and mass transfer limit conditions. This study provides ideas for reducing the use of precious metals and offers the possibility of targeted modulation of 2-MF hydrogenation products. [ABSTRACT FROM AUTHOR]

A Molybdate intercalated copper–aluminium hydrotalcite (CAM) material was synthesised using a simple co-precipitation technique, employing varying amounts of molybdate anions. Powder XRD, FT-IR, and TEM studies revealed the presence of molybdate species in the interlayer spaces and the formation of layered hydrotalcite structures. The resultant CAM materials have been explored for the hydrogenation of 5-hydroxymethyl furan using water as a green solvent in liquid-phase conditions under a hydrogen atmosphere. The catalyst showed around 60% conversion with the selective formation of 2,5-bishydroxymethyl furan (BHMF). The activity remains intact for five cycles. The increase in reaction temperature enhanced the conversion level to 80%, with the cost of a decrease in the selectivity of BHMF to 74%. The uniform dispersion of copper-molybdenum and strong interaction in the presence of a hydrogen atmosphere favoured better activity. [ABSTRACT FROM AUTHOR]

A calculation method for optimizing the LCOE and the cost of subsequent PTX production from wind power is presented, based on Weibull parameters and cost functions. The PTX products methanol, ammonia and synthetic diesel are considered, as well as hydrogen, which is converted into an easily transportable form by hydrogenation of a liquid organic hydrogen carrier (LOHC). Haru‐Oni in Chile and Tarfaya in Morocco were chosen as examples of production sites with excellent wind conditions. These are compared with three domestic sites with very good to very moderate wind conditions in the order Dornum (North German coast), Senftenberg (Lausitz) and Ludwigshafen (Rhine Graben). [ABSTRACT FROM AUTHOR]

Based on the geological and geochemical analysis of volcanic rock and their surrounding rocks, combined with palaeontological data and hydrocarbon generation thermal simulation experiments, the mechanism of the impact of volcanic eruptions on the formation of organic matter and hydrocarbon generation in the Dongying Depression is investigated. According to the results, underwater volcanic eruptions play a significant role in promoting biological eruptions and water stratification by introducing heat, minerals, and metal elements. The formation of the basalt source rock symbiotic association went through three evolutionary stages, which were underwater eruption, late eruption, and normal sedimentation. These stages have influenced the generation of hydrocarbons from organic matter in the following ways: (1) The organic acid released from the source rock dissolves the adjacent basalt, and the transitional metal elements in the basalt become activated and enter the source rock, which catalyses the hydrocarbon generation from the source rock. (2) Alteration of olivine in basalt releases hydrogen, improving hydrocarbon generation efficiency of source rock. (3) The existence of a large number of carbonates improves the hydrocarbon generation rate and efficiency of source rocks and reduces the hydrocarbon generation threshold of source rocks. [ABSTRACT FROM AUTHOR]

This paper outlines a novel strategy for the preparation of seven-membered-ring lactams from simple nitroarenes. The approach is based on a photochemical dearomative ring expansion starting with the conversion of the nitro group into a singlet nitrene. This process is mediated by blue light, occurs at room temperature and overall enables the insertion of the nitro N -atom into the benzenoid framework. This step transforms the aromatic starting material into a seven-membered ring azepine that, following hydrogenation and hydrolysis, is converted into the desired caprolactams in just three steps. [ABSTRACT FROM AUTHOR]

Hydrogenation of lignin-derived phenol to KA oil (the mixture of cyclohexanone (K) and cyclohexanol (A)) is attractive yet challenging in the sustainable upgrading of biomass derivatives under mild conditions. Traditional supported metal catalysts have been widely studied but the active components on supports often exhibit low recyclability due to their instability under experimental conditions. Here we show fabricating ultrasmall Pt/NiO in the pores of chromium terephthalate MIL-101 as catalysts for hydrogenation of phenol. Impressively, Pt/NiO@MIL-101 achieves catalytic phenol hydrogenation to KA oils of tunable K/A ratios and good reusability under room temperature and atmospheric hydrogen pressure, superior to contrast Pt@MIL-101 and Pt/NiO samples. Such excellent performance mainly originates from the effective adsorption and activation of phenol by coordinatively unsaturated Cr sites and H2 activation on ultrasmall Pt/NiO as well as its effective spillover to the adsorbed phenol over Cr sites for hydrogenation reaction. Substantially, such catalyst also displays the excellent performances for hydrogenation of phenol's derivatives under mild conditions. [ABSTRACT FROM AUTHOR]

A family of NiO‐MgO samples with Ni/Mg molar ratio between 0.10 and 0.30 are synthesized by co‐precipitation and subsequent calcination. The characterization of the samples show the formation of a solid solution with a periclase structure in such a way that the Ni2+species are poorly reducible. After the reduction of the NiO‐MgO samples at 500 °C, the catalysts are tested in the furfural (FUR) hydrogenation to obtain valuable products in a one‐pot reaction. The catalysts are highly selective toward tetrahydrofurfuryl alcohol (THFA) with a yield above 50% in most cases as well as 1,2‐pentanediol (1,2‐PeD) and 1,5‐pentanediol (1,5‐PeD) with maximum yield of 22 and 23% after 22 h of reaction at 170 °C and 4 MPa of H2, respectively. The present work also suggests the presence of two routes in the furfuryl hydrogenation. The first one is associated with the reduction of furfural to furfuryl alcohol (FOL) and the hydrogenation of the ring yielding THFA. In the second route, once FOL is formed, the furanic ring is open to form 1,2‐PeD and 1,5PeD. [ABSTRACT FROM AUTHOR]

Electrocatalytic semi-hydrogenation of acetylene (C2H2) over copper nanoparticles (Cu NPs) offers a promising non-petroleum alternative for the green production of ethylene (C2H4). However, server hydrogen evolution reaction (HER) competition in this process prominently decreases C2H4 selectivity, thereby hindering its practical application. Herein, a Cu-based composite catalyst, wherein porous carbon with nanoscale pores was used as a support, is constructed to gather the C2H2 feedstocks for suppressing the undesirable HER. As a result, the as-prepared catalyst exhibited C2H2 conversion of 27.1% and C2H4 selectivity of 88.4% at a C2H4 partial current density of 0.25 A/cm2 under optimal − 1.0 V versus reversible hydrogen electrode (RHE) under the simulated coal-derived C2H2 atmosphere, significantly outperforming the single Cu NPs counterparts. In addition, a series of in situ and ex situ experimental results show that not only the porous nature of the carbon support but also the stabilized Cu0–Cu+ dual active sites through the strong metal–support interactions enhance the adsorption capacity of C2H2, leading to high C2H2 partial pressure, restraining the HER and thus improving the C2H4 selectivity. [ABSTRACT FROM AUTHOR]

Improving the efficiency of metal/reducible metal oxide interfacial sites for hydrogenation reactions of unsaturated groups (e.g., C=C and C=O) is a promising yet challenging endeavor. In our study, we developed a Pd/CeO2 catalyst by enhancing the oxygen vacancy (OV) concentration in CeO2 through high-temperature treatment. This process led to the formation of an interface structure ideal for supporting the hydrogenation of methyl oleate to methyl stearate. Specifically, metal Pd0 atoms bonded to the OV in defective CeO2 formed Pd0–OV–Ce3+ interfacial sites, enabling strong electron transfer from CeO2 to Pd. The interfacial sites exhibit a synergistic adsorption effect on the reaction substrate. Pd0 sites promote the adsorption and activation of C=C bonds, while OV preferably adsorbs C=O bonds, mitigating competition with C=C bonds for Pd0 adsorption sites. This synergy ensures rapid C=C bond activation and accelerates the attack of active H* species on the semi-hydrogenated intermediate. As a result, our Pd/CeO2-500 catalyst, enriched with Pd0–OV–Ce3+ interfacial sites, demonstrated excellent hydrogenation activity at just 30 °C. The catalyst achieved a Cis–C18:1 conversion rate of 99.8% and a methyl stearate formation rate of 5.7 mol/(h·gmetal). This work revealed the interfacial sites for enhanced hydrogenation reactions and provided ideas for designing highly active hydrogenation catalysts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Hydrogenation of CO2 to synthesize CH4 (CO2 methanation) is one of the crucial pathways for the efficient and clean conversion of CO2. Despite extensive researches on the catalytic system for CO2 methanation, the intrinsic kinetics of CO2 methanation under specific conditions have not been thoroughly investigated. Ni/CeO2 catalyst (Ni mass fraction of 10%) was prepared using the combustion method, and samples with varying m(α-Al2O3):m(Ni/CeO2) were produced by incorporating α-Al2O3 as the internal diluent. The intrinsic kinetics of CO2 methanation of sample A with m(α-Al2O3):m(Ni/CeO2) = 25:1 were examined under the conditions of temperature of 300 °C, pressure of 1 MPa and gas hourly space velocity of 3 x 106 mL/(g⋅h). An in-depth analysis of the kinetic equations for the intrinsic CO2 methanation reaction was conducted through a combination of intrinsic kinetic tests, diffuse reflection infrared spectrum, H2-temperature programmed reaction and H2-temperature programmed desorption, etc. The results show that the CH4 generation rate under action of sample A can reach up to 41.4 mmol/(g⋅h)(H2 partial pressure is 400 kPa, and CO2 partial pressure is 120 kPa). When CO2 partial pressure is 30 kPa to 120 kPa, the CH4 generation rate exhibits linear increases with the rises of the H2 partial pressure, and is not affected by variation of the CO2 or CO partial pressure. Within this CO2 partial pressure range, the hydrogen-rich environment significantly enhances the catalytic activity of the catalyst for CO2 methanation. [ABSTRACT FROM AUTHOR]

CO2 hydrogenation to methane (also known as "CO2 methanation") is an important way to achieve the goal of carbon neutralization. CeO2 is considered as one of the most important catalyst supports because of its abundant surface oxygen vacancies and excellent oxygen storage capacity. Transition metal Ni is also widely studied because of its excellent catalytic performance and low price. The Ni/CeO2-based catalysts formed by the combination of CeO2 and metal Ni show good application prospects in CO2 methanation. The reaction mechanisms of Ni/CeO2-based catalysts for CO2 methanation were summarized and the preparation methods of Ni/CeO2-based catalysts were introduced, and the key parameters affecting catalytic performance of CO2 methanation such as the characteristics of active centers, properties of supports, types of additives and metal-support interactions were summarized, and the catalytic performances of Ni/CeO2-based catalysts were also summarized. It is found that by modifying Ni/CeO2-based catalysts, the catalytic performances and product selectivities of Ni/CeO2-based catalysts for CO2 methanation can be regulated, which can provide new ideas for improving their catalytic performances of CO2 methanation. [ABSTRACT FROM AUTHOR]

Abstract—The acoustic emission signals that arise during the interaction of metal zirconium samples with hydrogen, as well as the changes that occur in hydrogenated samples and are sources of high-amplitude acoustic signals, are studied. Hydrogenation of pieces of compact zirconium iodide ranging in size from 5 to 10 mm, shavings obtained from compact zirconium iodide with a linear particle size from 2 to 3 mm and a thickness of ≈0.2 mm, "coarse" electrolytic zirconium powder with a fraction from 80 to 550 μm, and "fine" electrolytic zirconium powder with a particle size of less than 80 μm is carried out. It is established that the source of high-amplitude acoustic signals in all cases is the cracking of zirconium particles at the macro level, which leads to the formation of extended cracks and fractures on the surface of individual particles, as well as to the grinding of the initial materials. Cracking and grinding are caused by deformation and internal stresses that arise in the samples owing to an increase in the volume of the solid phase during hydrogenation. It is shown for the first time that the atomic ratio [H]/[Zr] in the solid phase corresponding to the maximum amplitude of the acoustic emission signal naturally increases in the series pieces of compact zirconium iodide–shavings of zirconium iodide–"coarse" electrolytic zirconium powder–"fine" electrolytic zirconium powder, which is in good agreement with the results of earlier similar studies carried out on the hydrogenation of titanium metal samples. [ABSTRACT FROM AUTHOR]

Since catalytic chemoselective reduction of corresponding nitroarenes is a significant route to produce functionalized anilines, developing inexpensive and highly active catalyst is imperia. Herein, the Co‐Ce‐H2salen‐hmta composite was first prepared by grinded completely the mixture of Co‐H2Salen and hexamethylenetetramine (hmta) in 1:1 mol ratio in a mortar. The 3d–4f hetero‐metal Co‐Ce‐H2salen coordination polymer acted as a support precursor and hmta provided the nitrogen source. Then, a target catalyst of Co/NC‐CeO2‐hmta were afforded by pyrolysis of Co‐Ce‐H2salen‐hmta composite at 800°C in the presence of argon atmosphere. When the target catalyst of Co/NC‐CeO2‐hmta and reference catalysts were applied for the hydrogenation of nitroarenes under N2H4, the target catalyst of Co/NC‐CeO2‐hmta exhibited better performance than reference catalysts in terms of conversion, yield, selectivity, and recyclability. Spectral analysis suggested that the high catalytic performance of a target catalyst of Co/NC‐CeO2‐hmta were attributed to highly dispersed metallic Co0, rich oxygen vacancies, and nitrogen‐doped carbon matrix. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The increasing levels of carbon dioxide (CO2) in the atmosphere, primarily due to the use of fossil fuels, pose a significant threat to the environment and necessitate urgent action to mitigate climate change. Carbon capture and utilization technologies that can convert CO2 into economically valuable compounds have gained attention as potential solutions. Among these technologies, biocatalytic CO2 hydrogenation using bacterial whole cells shows promise for the efficient conversion of CO2 into formate, a valuable chemical compound. Although it was discovered nearly a century ago, comprehensive reviews focusing on the utilization of whole‐cell bacteria as the biocatalyst in this area remain relatively limited. Therefore, this review provides an analysis of the progress, strategies, and key findings in this field. It covers the use of living cells, resting cells, or genetically modified bacteria as biocatalysts to convert CO2 into formate, either naturally or with the integration of electrochemical and protochemical techniques as sources of protons and electrons. By consolidating the current knowledge in this field, this review article aims to serve as a valuable resource for researchers and practitioners interested in understanding the recent progress, challenges, and potential applications of bacterial whole cell catalyzed CO2 hydrogenation into formate. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogenation of unsaturated aldehydes to unsaturated alcohols is a promising alternative to conventional thermal processes. Both the catalyst and electrolyte deeply impact the performance. Designing the electrode‐electrolyte interface remains challenging due to its compositional and structural complexity. Here, we employ the electrocatalytic hydrogenation of 5‐hydroxymethylfurfural (HMF) as a reaction model. The typical cationic surfactant, cetyltrimethylammonium bromide (CTAB), and its analogs are employed as electrolyte additives to tune the interfacial microenvironment, delivering high‐efficiency hydrogenation of HMF and inhibition of the hydrogen evolution reaction (HER). The surfactants experience a conformational transformation from stochastic distribution to directional assembly under applied potential. This oriented arrangement hampers the transfer of water molecules to the interface and promotes the enrichment of reactants. In addition, near 100 % 2,5‐bis(hydroxymethyl)furan (BHMF) selectivity is achieved, and the faradaic efficiency (FE) of the BHMF is improved from 61 % to 74 % at −100 mA cm−2. Notably, the microenvironmental modulation strategy applies to a range of electrocatalytic hydrogenation reactions involving aldehyde substrates. This work paves the way for engineering advanced electrode‐electrolyte interfaces and boosting unsaturated alcohol electrosynthesis efficiency. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogenation of 1‐octene as non‐activated model substrate with neutral water as H‐donor is reported, using [(tBuPCP)Ir(H)(Cl)] (1) as the catalyst, to form octane with high faradaic efficiency (FE) of 96 % and a kobs of 87 s−1. Cyclic voltammetry with 1 revealed that two subsequent reductions trigger the elimination of Cl− and afford the highly reactive anionic Ir(I) hydride complex [(tBuPCP)Ir(H)]− (2), a previously merely proposed intermediate for which we now report first experimental data by mass spectrometry. In absence of alkene, the stoichiometric electrolysis of 1 in THF with water selectively affords the Ir(III) dihydride complex [(tBuPCP)Ir(H)2] (3) in 88 % FE from the reaction of 2 with H2O. Complex 3 then hydrogenates the alkene in classical fashion. The presented electro‐hydrogenation works with extremely high FE, because the iridium hydrides are water stable, which prevents H2 formation. Even in strongly alkaline conditions (Bu4NOH added), the electro‐hydrogenation of 1‐octene with 1 also proceeds cleanly (89 % FE), suggesting a highly robust process that may rely on H2O activation, reminiscent to transfer hydrogenation pathways, instead of classical H+ reduction. DFT calculations confirmed oxidative addition of H2O as a key step in this context. [ABSTRACT FROM AUTHOR]

Hydrogen spillover, the simultaneous diffusion of protons (H+) and electrons (e−) is considered to be applicable to ubiquitous technologies related to hydrogen but limited to over reducible metal oxides. The present work demonstrates that a non-reducible MgO with heteroatom Al dopants (Al–MgO) allows hydrogen spillover in the same way as reducible metal oxides. Furthermore, a H+ storage capacity of this material owing to hydrogen spillover is more than three times greater than those of various standard metal oxides based on H+ transport channels within its bulk region. Atomic hydrogen diffuses over the non-reducible Al–MgO produces active H+-e− pairs, as also occurs on reducible metal oxides, to enhance the catalytic performance of Ni during CO2 hydrogenation. The H+ and e− diffusion pathways generated by the heteroatom Al doping are disentangled based on systematic characterizations and calculations. This work provides a new strategy for designing functional materials intended to hydrogen spillover for diverse applications in a future hydrogen-based society. Hydrogen spillover is typically associated with reducible metal oxides and considered relevant for various hydrogen-related technologies. Here, the authors demonstrate that a non-reducible MgO doped with heteroatom Al enables hydrogen spillover similarly to reducible metal oxides. [ABSTRACT FROM AUTHOR]

Electrochemically reducing nitrate (NO3−), a common water pollutant, to valuable ammonia (NH3) offers a green, sustainable, and decentralized route for ammonia synthesis. Electrochemical nitrate reduction reaction (NO3−RR) involves two crucial reaction steps: nitrate deoxygenation followed by nitrite hydrogenation; in particular, the nitrite hydrogenation reaction is the rate‐determining step (RDS) for NO3−RR. In this work, an atomically dispersed cobalt‐phosphorus (Co─P) catalytic pair (CP) with strong electronic coupling is reported. The Co site in Co─P CP effectively activates NO3−, while the P site in Co─P CP facilitates water dissociation to release H+, synergistically enhancing the thermodynamic and kinetic performance of electrochemical nitrate reduction to ammonia. [ABSTRACT FROM AUTHOR]

Hydrogenating CO2 to produce light olefins is a highly promising route for olefin synthesis. However, the premise of achieving a high yield is to develop a catalyst with a high conversion rate, selectivity, and stability. This paper reports a Ca2−xKxFe2O5 catalyst with an CO2 conversion of up to 46%, a light olefin selectivity of 34.59%, and an olefin-alkane molar ratio of 8.31. Ca addition increased the oxygen vacancy concentration and strong basic sites of the catalyst, resulting in improved HCOO* intermediate formation, better CO selectivity, and higher CO2 conversion rates. Meanwhile, the addition of K further enhanced the rate of CO2 conversion while also improving the selectivity of light olefins by promoting C–C coupling. Furthermore, the Ca1.0K1.0Fe2O5 catalyst demonstrated no notable deactivation over a period of 72 h, indicating the strong industrial potential of this catalyst. [ABSTRACT FROM AUTHOR]

The natural sunlight‐driven conversion of CO2 into valuable C2+ products is urgently being pursued at ambient pressure, yet it poses a substantial challenge. Herein, a bifunctional Cu‐promoted CoFe alloy catalyst is designed for the natural light‐driven CO2 hydrogenation into light olefins. Under a weak solar‐irradiation intensity of 0.45 kW m−2 (0.45 sun), the optimal catalyst exhibits excellent activity and selectivity, with an impressive 73.7% selectivity for C2+ hydrocarbons and an outstanding 56.5% selectivity for C2‐4 olefins, which is the best catalyst for C2+ hydrocarbons photosynthesis from natural sunlight to date. The bifunctional design of the catalyst combines the advantages of both metallic Cu and CoFe alloy components, providing a synergistic effect that enhances the CO2 hydrogenation performance. The Cu promoter plays a crucial role in enhancing the adsorption of CO2 and hydrogen spillover, while the CoFe alloy provides a stable coupling site of the C1 intermediate for promoting the C2‐4 olefins. This study provides new insights into the design of bifunctional catalysts for CO2 hydrogenation and opens up new possibilities for sustainable production of light olefins from renewable resources. [ABSTRACT FROM AUTHOR]

In catalytic reactions, the diverse binding sites of nanometals located in nanomaterials considerably influence the activity of nanocatalysts. In this study, the special nanostructure and charge distribution of halloysite nanotubes (HNTs) incorporating a weak reducing agent closo-dodecaborate (closo-[B12H12]2-) were leveraged to immobilize Au nanoparticles (NPs) on the inner and outer surfaces of HNTs. The introduction of closo-[B12H12]2- into HNTs was achieved via vacuum extraction and acid immersion. Subsequently, nanocatalysts loaded with Au NPs on the diverse surfaces of the HNTs were obtained from a direct reaction with a KAuCl4 solution. The Au NPs loaded on the inner surface of the HNTs were found to have highly dispersed and exhibited excellent catalytic activity in the reduction of nitroaromatics. At room temperature, the Au NPs loaded on the inner surface of the HNTs with a mass fraction of 0.02% showed a high turnover frequency value of 47.28 min-1 in a model reaction of the catalytic reduction of 4-nitrophenol to 4-aminophenol and exhibited excellent stability in cycling tests. Therefore, this study provides a new approach for synthesizing nanocomposites for various practical applications. [ABSTRACT FROM AUTHOR]

Solvent effects add a new dimension for tuning the activity and selectivity of heterogeneous catalytic reactions, which is extensively employed in the hydrogenation of unsaturated compounds with multiple functional groups. In this concept, we briefly summarize recent developments on how the solvent effects affect the catalytic performance from the following aspects: 1) the polarity of the solvent can influence the interaction between the solvent and the reactant or intermediate; 2) the composition of mixed solvent can influence the reactivity of the reactant or intermediate; 3) solvent effect varies with the metal identity and support; 4) the solvent can induce surface modification of the supported catalysts. This summarization will provide insights into the rational development of efficient and selective heterogeneous hydrogenation catalytic system to realize the precise synthesis of desired chemicals. [ABSTRACT FROM AUTHOR]

CO2 emissions have received a great deal of attention in recent years. The hydrogenation of CO2 to higher alcohols (HA) by heterogeneous catalysis is a promising artificial carbon cycle pathway, which has important significance for mitigating energy and environmental problems. Among the heterogeneous catalysts, supported catalysts exhibit unique catalytic activity due to their abundance of surface‐tunable active sites such as oxygen vacancies, surface acidic/basic sites, and active hydroxyl groups. Given the complexity in the CO2 hydrogenation reaction networks, however, it is very challenging to reveal the nature and role of unique interfaces/sites induced by oxide support. Herein, we review the progress of several common oxide supports in the CO2 hydrogenation to HA over the last decades, and illustrate the regulatory mechanisms of the oxide‐induced synergy on the activation of intermediates and the C−C coupling reactions. Based on this, we also discuss the present challenges associated with the HA synthesis from CO2 hydrogenation, as well as the thinking oriented on oxide support‐induced structure changes to improve the selectivity and productivity of HA. [ABSTRACT FROM AUTHOR]

Direct asymmetric hydrogenation (AH) and asymmetric transfer hydrogenation (ATH) are among the most efficient approaches to produce chiral building blocks. Recently, these types of transformations have witnessed a shift towards the use of molecular catalysts based on earth‐abundant transition metals due to their ready availability, economic advantage, and novel properties. With particular regard to manganese, catalyst development has seen both the efficiency and substrate scope in AH and ATH greatly improved, with the emergence of a large number of well‐defined Mn‐complexes employed in this field. The reaction scope includes the AH and ATH of C=O bonds, asymmetric reduction of C=N bonds and the asymmetric reductive transformations of C=C bonds. Herein, our survey of the area focuses on the catalytic activity of such complexes, their versatility towards asymmetric transformations and the routes employed to convert substrates to their target molecules. We consider the collected findings of this article will be helpful to the reader by providing an insight into ligand design, thereby aiding future catalyst development. Moreover, this review is aimed at highlighting the remarkable progress made in the last seven years in the development of manganese complexes for enantioselective reduction. [ABSTRACT FROM AUTHOR]

Direct catalytic conversion of CO2 to methanol via renewable hydrogen has emerged as a promising technology among the various CO2 conversion techniques. However, efficient hydrogenation of CO2 using conventional Cu‐ZnO‐based catalysts, which are currently used for industrial methanol production from synthesis gas, remains a challenge due to inefficient energy conversion, poor stability and sluggish CO2 conversion kinetics. As the catalytic activity, stability and methanol selectivity of conventional Cu/ZnO catalysts are still insufficient for industrial applications, novel catalyst formulations using transition metals/metal oxides and supported noble metal nanostructures have emerged. Among them, intermetallic compounds are being explored for their unique electronic and crystalline structures, which can be tailored by controlled, precise, and seamless tuning of interatomic distances, specific arrangements and electronic structure to enhance their stability and activity for the selective hydrogenation of CO2 to methanol. In this context, intermetallic catalysts containing Pd, Cu and Ni combined with metal oxide nanoparticles (ZnO, Ga2O3, In2O3, etc.) have been shown to be more effective than the classical Cu‐ZnO‐Al2O3. This review analyses the progress made in the study of these intermetallic catalysts by analysing different aspects of their preparation, characterization, effects of promoters, support interactions, etc. Future research perspectives are discussed in the context of potential industrial applications of intermetallics for direct methanol production via CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

Research on the chemoselective metal‐catalyzed hydrogenation of conjugated π‐systems has mostly been focussed on enones. Herein, we communicate the understudied asymmetric hydrogenation of enimines catalyzed by N,P‐iridium complexes and chemoselective toward the alkene. A number of enoxime ethers underwent hydrogenation smoothly to yield the desired products in high yield and stereopurity (up to 99 % yield, up to 99 % ee). No hydrogenation of the C=N π‐bond was observed under the applied reaction conditions (20 bar H2, rt, DCM). It was demonstrated that the chiral oxime ether could be hydrolyzed into the ketone with complete preservation of the installed stereogenity at the α‐carbon. At last, a binding mode of the substrate to the active iridium catalyst and the consequence for the stereoselective outcome was proposed. [ABSTRACT FROM AUTHOR]

Developing chiral electrode catalysts for enantioselective electrosynthesis is a great challenge, as it requires catalysts that possess both high activity and enantioselectivity. Precise synthesis of nanoclusters and single atoms coexisting chiral catalysts provide a promising pathway for enhancing asymmetric catalytic performance. Herein, chiral electrode catalysts are fabricated comprising gold clusters (R‐AuC) and single atoms (R‐AuS) on graphene oxide (R‐AuC/S@GO) through an assembly‐irradiation strategy. Thereinto, the R‐Aus is in situ generated from R‐AuC under light irradiation. The monoatomization process can be precisely regulated by changing the wavelength of the light, resulting in four Au‐based chiral electrode (R‐Au@GO) catalysts with different ratios of nanoclusters and single atoms. These chiral electrodes are applied in the electrocatalytic enantioselective hydrogenation of methyl benzoylformate (MB) to chiral methyl mandelate (S‐MM), and the R‐AuC/S‐2@GO with ≈26% R‐AuC and 74% R‐AuS achieve the highest catalytic activity (35 µmol cm−2 h−1 productivity) and enantioselectivity [97% enantiomeric excess (ee)]. Detailed experimental analysis and density functional theory calculations reveal that the R‐AuS on GO promotes the in situ generation of H* species, and R‐AuC mainly drives the enantioselective conversion of MB by transferring the H* species to the carbonyl group of MB, ultimately yielding chiral S‐MM. [ABSTRACT FROM AUTHOR]

The precise effect of oxide understoichiometry on bulk oxide catalytic properties continues to remain a subject of intense investigation. Of specific interest in this regard is the role of oxygen vacancies present on bulk ceria catalysts that have recently been reported to represent a more cost‐effective alternative to the more toxic and expensive catalysts used industrially for the selective hydrogenation of acetylene to ethylene. Contrasting claims as to the effect of surface reduction on hydrogenation rates exist in the open literature, with vacancy formation attributed, in separate studies, either a favorable or a deleterious role in effecting hydrogenation turnovers. We report here the non‐monotonic behavior of ethene hydrogenation rates that subsumes both of these trends as a function of degree of surface reduction over a sufficiently large range of pre‐reduction temperatures. Steady state transient kinetic and isotopic exchange data combined with in‐situ titration experiments suggest that this non‐monotonic trend can be attributed not to a change in either the kinetic relevance of specific elementary steps or the hydrogenation mechanism, but rather to site requirements that stipulate the need for two distinct, proximal sites. We also show that the sensitivity of hydrogenation rates to surface reduction can be altered by varying ceria surface termination, with the more open (110) and (100) surfaces exhibiting a less asymmetric effect of surface reduction on ethene hydrogenation rates. [ABSTRACT FROM AUTHOR]

Kinetic model development is integral for designing, redesigning, monitoring, and optimizing chemical processes. Of the various approaches used within this field, microkinetic modeling is a crucial tool that focuses on surface events to analyze overall and preferential reaction pathways. This work covers noticeable features of microkinetic modeling for three critical case studies: (i) ammonia to hydrogen, (ii) oxidative coupling of methane to chemicals, and (iii) carbon dioxide hydrogenation for methanol synthesis. We analyze how microkinetic modeling enables predicting and optimizing complex reaction networks, allowing the design of efficient and tailored catalysts with enhanced activity and selectivity. [ABSTRACT FROM AUTHOR]

A simple and recyclable homogeneous catalytic system for the hydrogenation of carbon monoxide to methanol was established. The reaction is catalyzed by a molecular manganese complex using a high-boiling alcohol as the solvent for catalyst immobilization. The CO hydrogenation is assisted by the product itself and the solvent through the formation of a methyl or dodecyl formate ester intermediate mediated by catalytic amounts of NaOMe as the base. This allows the catalytic formation of methanol in alcohols combined with facile product separation and catalyst recycling via distillation. Initial turnover frequencies (TOF) of 2250 h−1 were reached under optimized conditions in 1-dodecanol/methanol as the reaction medium (T = 160 °C, p(H2/CO) = 80/10 bar). The performance was stabilized in batch-wise recycling over 6 runs achieving a total turnover number (TTON) of >12 000 corresponding to an enhancement of more than five times compared to single batch operation under identical conditions. Minimal leaching of the components of the organometallic catalyst was observed during distillative product separation and catalyst activity could be fully restored by re-addition of the base NaOMe. [ABSTRACT FROM AUTHOR]

Biomass provides a promising source of carbon for obtaining environment-friendly carbon materials, but obtaining heteroatom-doped carbon materials (HDCMs) from biomass directly by a green method still remains challenging. This study successfully synthesized nitrogen and phosphorus co-doped porous carbon materials (Y-NPC) by the simple in situ pyrolysis of renewable yeast mixed with water from 800 to 950 °C. Various characterization methods show that nitrogen and phosphorus are doped into the carbon skeleton and mainly exist in the forms of graphite-N, pyridine-N, C–P, P–N, and P–O states. The catalyst Y-NPC-900 °C with a 3D hierarchical porous structure and high P–N content exhibited superior nitro hydrogenation performance and reaction stability using molecular hydrogen and hydrazine hydrate as hydrogen sources under mild conditions. Density functional theory (DFT) calculations and experiments attributed the exceptional catalytic performance to hydrogen activation and the good adsorption ability of substrates over N, P co-doped carbon (NPC). Therefore, this research proposes an eco-friendly and simple synthesis strategy for in situ N, P co-doping metal-free carbon catalysts derived from biomass, showing the significance of N, P co-doping and single N- or P-monodoping in the charge distribution of carbon materials. [ABSTRACT FROM AUTHOR]