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The issue of excess slag waste generated in the iron and steel making industries has prompted investigations on the use of the slag waste. The objective of this study is to develop an adsorbent capable of capturing carbon dioxide (CO 2) by using waste slag. A mesoporous CaO-Fe 2 O 3 -SiO 2 (CFS) composite was synthesized from a dephosphorization steel slag, using Pluronic 123 as a template and various acids, including formic acid (FA), hydrochloric acid (HCl), and nitric acid (HNO 3). The morphological and physicochemical features of the prepared samples were determined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N 2 adsorption-desorption measurements. The capability of the adsorbent to capture CO 2 was investigated in repeated CO 2 adsorption cycles. In comparison to other samples, the slag-derived adsorbent synthesized using formic acid (deP-CSF(FA)) exhibited the highest CO 2 adsorption capacity (17.0 wt% per mass of adsorbent) and better regenerative ability. A regenerative CaO-based adsorbent synthesized from a dephosphorization slag that is environmentally friendly and economical, as well as having a high capacity for CO 2 adsorption and reuse, is advantageous for reducing CO 2 emissions from the iron and steel making industry and will undoubtedly contribute to the industry's long-term sustainability. A CaO-Fe 2 O 3 -SiO 2 composite was synthesized from dephosphorization slag and applied for CO 2 adsorption [Display omitted] • A CaO-based adsorbent is produced from dephosphorization slag through a facile chemical process. • The adsorbent prepared with formic acid and P123 exhibits the highest CO 2 adsorption capacity. • The slag-derived adsorbent also shows a faster adsorption rate and better cycling stability. • This works provides a simple and low-cost method to prepare CaO-based adsorbent from waste steel-making slag. [ABSTRACT FROM AUTHOR]

• A series of Ag-based catalysts on metal oxide support materials were prepared. • Chemoselective reduction of p -NS is studied under visible light irradiation. • Ag/TiO 2 was found to be most active amongst all under visible light irradiation. • Plausible mechanism is proposed for the enhanced selective performance. The localized surface plasmon resonance (LSPR) mediated enhanced chemical activity can be entitled as a promising strategy for efficient solar to chemical energy conversion. To tune the selectivity of a desired product in a chemical reaction is of paramount importance yet a great challenge. In this paper, a new strategy to effectively enhance the selectivity of the product formation under visible light irradiation is reported. A series of Ag catalysts deposited on metal oxide support materials (TiO 2 , ZrO 2 , Al 2 O 3 and CeO 2) along with their preparative techniques, optimum metal content ratio and effect of different wavelength of light is explored for the chemoselective reduction of p -nitrostyrene to p -aminostyrene under visible light irradiation. The prepared catalysts were characterized by a range of physicochemical techniques including UV–vis, transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The reduction reaction was carried out in ethanolic suspension at room temperature and pressure utilizing ammonia borane (AB) as an in-situ source of H 2. The reaction results displayed 100% conversion with a maximum chemoselectivity of 81% shown by Ag/TiO 2 under light irradiation conditions. The high chemoselectivity could be attributed to the preferential alignment of polar nitro group on the surface of plasmonic silver under light irradiation conditions. [ABSTRACT FROM AUTHOR]

Especially in the context of current greenhouse effect and energy shortage, the development of various catalysts to catalyze CO 2 resource utilization is an attractive field. Recently, the yolk-shell catalyst solves the problems of coking and sintering and further provides confinement effects as well as improved stability. In this mini-review, the development status of carbon, silicon-based yolk-shell structured catalysts for hydrogenation of CO 2 to formate/formic acid, and CO 2 dry reforming of methane are introduced. The latest research progress of catalysts and active metals commonly used in these reactions is reviewed, as well as how to provide superior performance in these reactions. In addition, the properties of customized yolk-shell structure and the effect of pore size change on CO 2 hydrogenation and dry reforming reaction will be briefly described. Furthermore, the effect of space restriction and how to enhance the performance of the yolk-shell structure nanoreactor are also discussed. We firmly believe that this mini-review will stimulate more research in the catalysis community, especially to advance the design of yolk-shell catalytic materials, and ultimately achieve sustainable development of the carbon cycle. [Display omitted] • The advantages, synthetic methods of yolk-shell structured catalysts for CO 2 reduction were summarized. • Different types of yolk-shell structures exhibited excellent performance in CO 2 reduction. • Challenges and future prospects in the development process were discussed. [ABSTRACT FROM AUTHOR]

Localized surface plasmon resonances (LSPR) in near-infrared (NIR) region have been extensively studied for copper chalcogenide nanostructures, not only for the absorption enhancement but also tunable LSPR characteristics with their free carrier concentrations or defects. In the present work, one-step cation exchange method has been used to synthesize Cu 2−x S nanowires with x varied between 0 and 1, including Cu 2 S, Cu 7 S 4 and CuS and so forth. The plasmonic band of Cu 2−x S nanowires shifts to a shorter wavelength with the increase in x, as observed in vis-NIR spectra, which is attributed to the increase in density of copper vacancies. The Cu 2−x S nanowires have been used as catalysts towards the photocatalytic generation of H 2 from ammonia borane (AB). Among samples with different Cu-S compositions, Cu 7 S 4 samples exhibited the highest activity in terms of H 2 evolution rate (25.54 mmol/g h). Moreover, a marked enhancement of the H 2 evolution rate (157.04 mmol/g h) could be achieved after decorating the Cu 2−x S nanowires with Pd nanoparticles to form the hybrid structures. The results of the present investigation may lead to an effective strategy for the design and development of LSPR materials for photocatalytic applications. [ABSTRACT FROM AUTHOR]

Highlights: [•] A series of sulfated Si-doped ZrO2 were synthesized and characterized in detail. [•] Ethyl levulinate was produced from levulinic acid and ethanol with high yields. [•] The catalytic activity far outperformed that of the conventional sulfated zirconia. [•] A distinct correlation was observed between the activity and textural properties. [•] The catalyst could afford levulinate ester directly from cellulosic sugars. [ABSTRACT FROM AUTHOR]

[Display omitted] • Zinc, released from bioactive materials, was incorporated into dentin with in approximately 50 µm. • Zinc-doped dentin demonstrated 30% less acid solubility, helping to improve its anti-carcinogenicity. • Zinc was incorporated into dentin in a four-fold coordination , indicating a newly generated covalent bond. • Quantum beam and synchrotron radiation technologies help in analyzing the bonding states of dentinal elements. Dental caries, the world's most prevalent infectious disease, is caused by the diffusion of hydroxyl ions into tooth structures. To prevent dental caries, the application of fluoride (F) and zinc (Zn) ions to teeth surfaces are potential effective measures. In this study, The ionic influence, especially the chemical bond of F and Zn, on the acid resistance of dentin were investigated by particle induced X-ray / gamma-ray emission, X-ray diffraction, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. The results showed Zn was distributed in the limited surface layer of dentin without altering its crystal structure. From the Zn K edge extended X-ray absorption fine structure, Zn incorporated into dentin was surrounded by oxygen and demonstrated four-fold coordination. The bond length and chemical state of Zn–O in Zn doped dentin suggested newly generated Zn–O covalent bond, which may improve acid resistance of dentin. This study showed that the atomic and molecular structures, such as the molecular distances and chemical state, influenced acid resistance of teeth, emphasizing the validity of chemical state analysis for understanding properties in biomaterials. [ABSTRACT FROM AUTHOR]

Highlights: [•] A strategy that contributes to both waste and carbon management is proposed. [•] Layered double hydroxide (LDH) compound can be synthesized from blast furnace slag. [•] The slag-made LDH efficiently catalyzes the addition reaction of epoxides with CO2. [•] The slag-derived impurity elements act as catalyst promoters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogenation of CO 2 to formic acid with Pd-based catalyst has been reviewed. • Effect of PdM alloys and N functionalities on the catalytic activity was elucidated. • Successful strategies to maximize the performance catalytic activity were assessed. • Challenges and future directions in the hydrogenation of CO 2 discussed in the end. The "greenhouse effect" caused by presence of the large amounts of carbon dioxide (CO 2) is becoming extremely serious for the environment. Therefore, it is crucial to advance the progress of practical technologies to minimize the CO 2 emissions. The catalytic CO 2 hydrogenation with hydrogen (H 2) to form formic acid/formate over Pd-based catalysts has been considered as an effective technology to deal with environment and CO 2 emission issues. In the past decades, increasing efforts have been contributed to these fields and significant achievements have been obtained. In this review, the state-of-the-art of Pd-based heterogenous catalysts for catalytic conversion of CO 2 to formate/formic acid is systematically summarized. First, the key factors associated with catalytic performance are discussed including Pd metal dispersion, electron density of Pd metal and acidity of supports. Second, major achievements on the design of efficient Pd nanometal supported on various materials, mainly metal-organic frameworks (MOFs), carbon materials, silica, zeolites and other porous material, are summarized. Third, the successful strategies applied to maximize catalytic activity of CO 2 conversion by reducing the particle size of Pd, alloying foreign metal with Pd to change the electron density of Pd, as well as anchoring of functional groups were also highlighted. Special attention has been given to the mechanism of the catalytic reaction. Finally, a brief perspective to the challenges and new directions in the development of innovative catalytic materials to achieve high catalytic activity in CO 2 conversion is also proposed, which would be of great interest in realizing carbon-neutrality in near future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Core–shell-structured nanocomposite photocatalysts were designed and synthesized. • Single-site Co species were immobilized into g-C 3 N 4 via a simple pyrolysis process. • Co-doped g-C 3 N 4 coats the surface of Au nanorods via electrostatic self-assembly. • Surface plasmon resonance of Au promoted CO production on single-site Co species. • The core–shell structure is key to achieving high activity in the plasmonic catalysis. Designing efficient photocatalyst materials for CO 2 reduction and utilization has become important to address environmental and energy concerns. A new type of core–shell-structured nanocomposite catalyst is reported herein, in which single-site Co catalytic species are immobilized in graphitic carbon nitride (g-C 3 N 4) layered on Au nanorods (NRs) for surface plasmon resonance (SPR)-enhanced photocatalytic CO 2 conversion. Single-site Co species were incorporated into g-C 3 N 4 via a simple pyrolysis process, and core–shell nanocomposites were self-formed via electrostatic interactions between the positively charged surfaces of the Au NRs and negatively charged single-site Co-coordinated g-C 3 N 4 layer. The structure was comprehensively examined by TEM, XRD, UV–vis, Co K-edge XAFS, FT-IR, and zeta potential measurements, which showed that the g-C 3 N 4 layer did not prevent the Au NRs from absorbing visible light. The nanocomposite efficiently catalyzed the reduction of CO 2 to CO under visible light irradiation with the assistance of the SPR of the Au NRs. The catalytic activity of the core–shell-structured catalyst was superior to that of the corresponding aggregated catalyst, demonstrating that the formation of a core–shell structure affords efficient electron transport from the Au NRs to the catalytically active Co species. [ABSTRACT FROM AUTHOR]

[Display omitted] • Titanosilicates with different characteristic properties were synthesized. • Titanosilicates were tested in cyclooctene epoxidation with H 2 O 2 and aerobic photooxidation. • Reactants diffusion was improved by interlayer space or mesoporous structure. • Relationship between catalytic activity and structural properties was discussed. Bulky epoxides are industrially produced by organic synthesis in multistep procedures, generating significant amounts of waste products in the process. Efficient catalyst in combination with a simple oxidant (H 2 O 2 or O 2) would significantly reduce the waste production. Four types of microporous titanosilicates with extra-large pores (Ti-UTL), and shortened diffusion pathways (L-TS, Ti-MCM-22, and Ti-SPP) were prepared and investigated in the epoxidation of cyclooctene with H 2 O 2 and photocatalytic oxidation using O 2. Ti-UTL is a zeolite possessing 14−12-ring channel system. l -TS-1 and Ti-MCM-22 are composed of aggregates of titanosilicate nanosheets with the thickness of ca. 2 nm and hexagonal thin platelets, respectively. Ti-SPP is composed of olive-like aggregates with approximately length of 0.88–1.12 μm and width of 0.44−0.68 μm consisting of intergrown (self-pillared) nanosheets having 13−70 nm in size. In the epoxidation with H 2 O 2 as an oxidant, Ti-MCM-22 showed the highest catalytic activity due to the wide interlayer space, which enhanced the accessibility of cyclooctene to active titanium site. While, in the photocatalytic epoxidation in the presence of O 2 instead of H 2 O 2 , Ti-UTL showed the highest activity. The incorporated germanium atoms, which is indispensable component for the construction of extra-large pores, may affect the electronic properties of active titanium species, leading to high photocatalytic activity. [ABSTRACT FROM AUTHOR]

• Nano-sized plasmonic gold particles were synthesized on TiO 2 support material. • The morphology of TiO 2 was tuned to be nanotube, nanorod and microporous particles. • Au/TiO 2 catalysts were tested in the controlled oxidation reaction of benzyl alcohol. • Plausible mechanism was proposed for the enhanced activity under visible light. In the present research study, we report the synthesis of nano-sized gold (Au) particles immobilized on TiO 2 support material. The morphologies of TiO 2 support material was tailored and tuned to be rod, tube and microporous materials. The effect of plasmonic gold nanoparticles (NPs) deposited on different morphologies of TiO 2 was studied. The prepared catalysts were characterized by various characterization techniques in order to have a detailed insight on the textural properties, morphology and electronic state of the material via UV–vis spectroscopy, N 2 physisorption analysis, Transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). We tested the controlled oxidation of benzyl alcohol to benzaldehyde using molecular oxygen at 373 K under atmospheric pressure. The results obtained from the thermal reaction conditions were compared with those performed under visible light irradiation (λ > 420 nm) at 373 K. Among all, Au/TiO 2 nanorod catalyst displayed the superior performance of 33% yield in the absence of light and 55% yield of benzaldehyde with an external quantum efficiency of 3.4% under visible light irradiation (λ ≥ 420 nm) at 373 K for 4 h. The enhanced catalytic performances were attributed to the Au-LSPR phenomenon and a plausible reaction pathway has been discussed involving the generation of hot electrons during the course of reaction. [ABSTRACT FROM AUTHOR]

• Lanthanum Strontium Cobalt (LSC) perovskites were prepared by sol-gel method. • Doped-LSC perovskites were assessed in ammonia borane decomposition. • The closer interaction Cu-Co might be favoring the catalytic activity. • Cu doping was found to be a good option to boost the catalytic activity. Lanthanum Strontium Cobalt (LSC) perovskite-based catalysts were prepared and evaluated in the ammonia borane dehydrogenation reaction. Doping with additional non-noble metals, such as Ni or Cu greatly enhanced the catalytic performance, especially in the case of Cu. In order to evaluate the effect of the Cu loading, catalysts with various Cu contents ranging from 0.82 to 5.42 wt.% were synthesized. It was found that the Cu-doped sample with a nominal formula of La 0.7 Sr 0.3 Co 0.90 Cu 0.10 O 3 containing 2.72 wt.% of Cu displayed the highest catalytic activity among investigated, which outperformed the counterpart Cu-supported catalyst (Cu/La 0.7 Sr 0.3 CoO 3). La 0.7 Sr 0.3 Co 0.90 Cu 0.10 O 3 showed good durability during five consecutive reaction runs, confirming the suitability of perovskite-type catalysts in stabilizing the catalytic active phase. The present catalytic system provides a cost-effective alternative to the noble-metal-based catalysts commonly used to catalyze the ammonia borane dehydrogenation reaction. [ABSTRACT FROM AUTHOR]

Carbon/g-C 3 N 4 composites (C/g-C 3 N 4 ) with various carbon contents have been prepared by a simple experimental protocol from glucose and dicyandiamide. The results of the characterization of the as-prepared materials indicated that the skeleton structure of g-C 3 N 4 was not altered upon formation of the composite supports and the resulting composites showed a gradual increasing light harvesting capability with the carbon content. Ru-supported catalysts were synthesized from C/g-C 3 N 4 and assessed in the ammonia borane dehydrogenation reaction under dark and visible light irradiation conditions. The enhanced performance displayed by Ru/C/g-C 3 N 4 photocatalysts as compared to Ru/g-C 3 N 4 counterpart might be the result of the effect of the addition of carbon in dispersing and stabilizing small Ru nanoparticles and enhancing the optical absorption properties. [ABSTRACT FROM AUTHOR]

The studies on the phenomenon of surface plasmon resonance effect by noble metal-based nanoparticles (NPs) have largely been focused on the quantitative enhancement of reaction rates and investigating the mechanistic pathway of the reaction. However, the detailed analysis of the structure-property relation of plasmonic NPs and catalytic performance along with the contribution of absorption vs scattering remains limited. This report focuses on the comparison of the catalytic performance of different aspect ratio of gold nanorods (Au NRs) coupled with Pd-rGO nanocomposite for boosting the product yield of Suzuki-Miyaura coupling reaction under visible light irradiation. The confirmation of the successful synthesis of the Pd/Au NRs@rGO catalyst was done by multiple characterization techniques such as XRD, UV–vis, TEM, XAS, XPS and ICP. Amongst the three different aspect ratios of Au NRs, the superior catalytic performance of medium-sized NRs (length: 56 nm; diameter: 18 nm) with a TON of 50 was achieved under visible light irradiation conditions. A drastic enhancement by a factor of 4.1 was shown by the medium-sized NRs when the reaction results were compared in dark reaction conditions. The obtained enhancement has been ascribed to the higher efficiency of hot electron generation by the SPR effect of Au NRs. [Display omitted] • Au NR-based Pd-rGO plasmonic catalyst with different aspect ratios were designed. • Suzuki-Miyaura reaction (with and without light) was tested as the model reaction. • A superior TON by the medium-length Pd/Au NRs@rGO under light irradiation. • Higher activity was attributed to the higher efficiency of hot electron generation. [ABSTRACT FROM AUTHOR]

Abstract: TiO2 photocatalyst loaded on Si3N4 (TiO2/Si3N4) was prepared by a conventional impregnation method and its photocatalytic performance for the degradation of organics (2-propanol) diluted in water was compared with that of TiO2 photocatalysts (TiO2/SiO2, TiO2/Al2O3, and TiO2/SiC) loaded on various types of supports (SiO2, Al2O3, and SiC). The formation of the well-crystallized anatase phase of TiO2 was observed on the calcined TiO2/Si3N4 photocatalyst, while a small anatase phase of TiO2 was observed on the TiO2/SiC photocatalyst and amorphous TiO2 species was the main component on the TiO2/SiO2 and TiO2/Al2O3 photocatalysts. The measurements of the water adsorption ability of photocatalysts indicated that the TiO2/Si3N4 photocatalyst exhibited more hydrophobic surface properties in comparison to other support photocatalysts. Under UV-light irradiation, the TiO2/Si3N4 photocatalyst decomposed 2-propanol diluted in water into acetone, CO2, and H2O, and finally, acetone was also decomposed into CO2 and H2O. The TiO2/Si3N4 photocatalyst showed higher photocatalytic activity than TiO2 photocatalyst loaded on other supports. The well-crystallized TiO2 phase deposited on Si3N4 and the hydrophobic surface of Si3N4 support are important factors for the enhancement of photocatalytic activity for the degradation of organic compounds in liquid-phase reactions. [Copyright &y& Elsevier]

This work presents the synthesis of Pd-loaded microporous titanosilicalite-1 (Pd/TS-1) and Pd-loaded hierarchical titanosilicalite-1 (Pd/HTS-1) with abundant mesopores (2–30 nm) inside the framework via hydrothermal method using polydiallydimethyl ammonium chloride as the non-surfactant mesopore template. XRD, N 2 sorption, FT-IR, FESEM-EDX, TEM, XPS, and DR-UV techniques were used to characterize the morphological and physicochemical properties of the synthesized materials. These materials were tested as heterogeneous catalysts, along with tetrapropylammonium bromide as co-catalyst, for cycloaddition reactions of CO 2 with epoxides to produce cyclic carbonates. It was found that the epoxide conversions were influenced by acidity and pore accessibility of the catalysts. Using Pd/HTS-1 facilitated bulky substrates to access active sites, resulting in higher conversions than Pd/TS-1. Over 85 % conversions were achieved for at least five consecutive cycles without significant loss in catalytic activity. The interaction between the Pd active surfaces and epichlorohydrin (ECH) was further studied by DFT calculations. The existence of Pd(200) was more influential on adsorbing epichlorohydrin (ECH) and subsequent formation of dissociated ECH (DECH) intermediate than Pd(111) surface. However, Pd(111) was dominant in enhancing the activity of DECH species for capturing CO 2. Therefore, the co-existence of Pd(200) and Pd(111) surfaces was needed for cycloaddition of CO 2 with ECH. [Display omitted] • Novel Pd/HTS-1 showed high potential for catalyzing CO 2 cycloaddition with epoxides. • Catalyst had enhanced Lewis acid sites and high accessibility to HTS-1 active sites. • Effects of Pd surface on its interaction with ECH were investigated computationally. • Pd(200) and Pd(111) surfaces were proven to promote adsorption of ECH to capture CO 2. [ABSTRACT FROM AUTHOR]

The decoration of MWCNT in Cu/TiO 2 catalyst improved the H 2 production. [Display omitted] • Photocatalysts based on transition metals supported on TiO 2 MWCNT were synthesized. • The presence of MWCNT improved the H 2 production from ammonia borane. • Cu-based photocatalysts displayed the best activity among investigated. • The catalytic activity depended on the Cu content. • Cu1%/TiO 2 -MWCNT was the most active photocatalyst. In this study, we assessed the effect of the incorporation of multi-walled carbon nanotubes (MWCNT) on a TiO 2 support containing different active metals to obtain Metal/TiO 2 -MWCNT photocatalytic systems. The materials prepared in this work were characterized by ICP-OES, TEM, EDX, XRD, PL, UV–vis, and nitrogen physisorption techniques. Among those investigated metals, Cu was shown to be the most promising for the present application. The assessment of the photocatalytic performance of Cu/TiO 2 -MWCNT with various Cu contents revealed that the catalytic activity depends on the Cu loading and the photocatalyst with 1 wt.% of Cu displayed the best performance among investigated. The incorporation of MWCNT in the support enhanced the photocatalytic activity towards the production of H 2 under visible and UV–vis light irradiation at room temperature. [ABSTRACT FROM AUTHOR]

Porous materials are outstanding catalysts in various reactions using confinement and shape selectivity effects. Unsurprisingly, extensive research has been conducted on zeolites, pillared clays, metal oxides, metal organic frameworks, and mesoporous materials. In particular, selective oxidation of hydrocarbons stands out an important class of reactions, but the ability to avoid over-oxidation remains a challenge. Thus, the present review highlights the latest findings on octahedral and tetrahedral catalytic materials in oxidation reactions, primarily focusing on types of reactive oxygen species and approaches to their investigation, on the incorporation of different heteroatoms (Ti, Sn) into silica matrices for catalytic purposes and corresponding types of reactions and on surface engineering and design of "single-site catalysts". In addition, composite catalysts for one-pot selective oxidation reactions are reviewed, providing examples from photochemistry including "single-site photocatalysis", electrocatalysis, and integration of metal complexes with functional solid materials. Ultimately, the end goal of this review is to discuss current state-of-the-art approaches that are being used in the area of selective catalytic oxidations with some novel porous materials. This includes methods that are being used to study mechanistic details as well as new catalysts and new substrates for such oxidations. [ABSTRACT FROM AUTHOR]

The catalytic ability of graphitic carbon nitride (g-C 3 N 4)-supported composition-controlled PdCo catalysts towards H 2 generation from the formic acid dehydrogenation reaction was assessed in this study and a noticeable composition dependence was evidenced. It was seen that the alloying effect combined with the nitrogen functionalities present on g-C 3 N 4 assisted the formation of small and well-distributed nanoparticles. This fact, combined with the electronic promotion of Pd species via charge transfer from Co and basic features of the support, resulted in enhanced catalytic activities compared to that displayed by the counterpart Pd/g-C 3 N 4 , reaching a TOF value of 1193 h−1 for the most active catalyst among investigated (PdCo/g-C 3 N 4 (1/0.7)). Furthermore, the present catalytic system showed high selectivity towards formic acid dehydrogenation, suppressing the generation of undesired CO via formic acid dehydration, which makes it a suitable candidate for practical application in fuel cells. Image 1 • Small NPs achieved because of alloying effect and N-functionalities of the support. • Electronic promotion of Pd species via charge transfer from Co. • Activity of PdCo/g-C 3 N 4 related to the size of NP, composition and electronic state. • PdCo/g-C 3 N 4 (1/0.7) was the most active among investigated with a TOF of 1193 h−1. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The importance of H 2 in the renewable and pollutant-free energy scenario is pointed out. • Synthetic strategies of N-doped carbon materials and related catalysts are summarized. • HCOOH, NH 3 BH 3 and H 2 O are exemplified as hydrogen molecular carriers. • N-functionalities play a key role in attaining highly performing catalysts for H 2 production. Abstract Nitrogen-doped carbon materials have emerged as versatile candidates with outstanding features as both support of metal-based catalysts and metal-free catalytic systems. Their use has been traditionally linked to electrochemical applications, but the number of applications in which these materials show their virtues has been exponentially increasing in the last decade. Particularly, catalysts based on metal nanoparticles supported on nitrogen-doped carbon materials have shown to be attractive for important catalytic reactions as they display enhanced performances endowed by well-dispersed, stabilized and electronically promoted nanoparticles as well as by the modified acid-base properties of the support. The present review is focused on the most recent breakthroughs achieved by these catalytic systems in the hydrogen production from some of the most representative hydrogen carrier molecules by highlighting the effect of the incorporation of nitrogen in the support matrix. [ABSTRACT FROM AUTHOR]