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A series of nanoporous carbons was obtained by physical activation of polyethylene terephthalate and investigated for the separation of CO2 from flue gas. The prepared carbons exhibited extremely low functionalization—negligible content in oxygen and other heteroatoms—accompanied by well-developed porous networks consisting of gradually increasing surface areas and micropore volumes. Such features allowed to study the role of nanopore confinement in the separation of carbon dioxide in CO2/N2 gas mixtures. The analysis of the adsorption isotherms of individual gases and their mixtures revealed different trends for the CO2 uptake and the selectivity. Whereas CO2 uptake was larger in the carbons with higher burn-off degree, the selectivity of CO2 over N2 was favored in the carbons with a higher fraction of narrow micropores. The differential adsorption enthalpy curves are typical of highly microporous samples reaching values close to those found in zeolites for low loadings. Data also show that the choice of the best adsorbent for cyclic gas adsorption and separation processes should consider a broad context, taking into account various parameters simultaneously such as gas selectivity, working capacity, adsorption enthalpy and energy consumption in the synthesis of the adsorbent.

The photocatalytic activity of a series of novel KSrNbO materials was studied using the photooxidation of methylene blue as model reaction. The influence of the calcination time upon the crystalline structure and photoactivity was verified. Characterization was performed by XRD, SEM, FTIR, UV–Vis/DR, Helium picnometry, and N and CO adsorption-desorption isotherms. The diffraction line profile and the refinement of the structural parameters of KSrNbO were obtained from the XRD patterns by the Rietveld method. Data showed that samples were photoactive under UV irradiation, regardless the synthesis conditions. However, the calcination time had a clear influence upon the photocatalytic activity of the samples, being more efficient towards the degradation of the dye those obtained at a lower calcination time. Indeed, the sample calcined for 4 h showed up to 4 times higher photocatalytic activity than commercial TiO. Additionally, a correlation between the photocatalytic activity and the displacement of the Nb ion from the central position in the [NbO] octahedron was found. It is suggested that this fact causes an important polarization of the niobate structure. The apical oxygen in these samples is very reactive and can lead to the formation of superoxoradical anions (O ) showing that KSrNbO can be potentially used in photocatalytic reactions under UV irradiation., J. Matos thanks to the Chilean grants (Basal ProgramPFB-27, FAE-829, FONDEF-IDEA #ID15I10321, CORFO15IPPID-45676, FONDECYT1161068), for their financial support. S. Lanfredi thanks FAPESP (grants 2007/03510-9, 2014/11189-0, CNPq and UNESP/PROPe), for their financial support. C.O. Ania thanks the financial support of the Spanish MINECO (grant CTM2011/56770-R).

International audience; In order to help unravel the thermal history of middle Paleozoic sedimentary rocks in West Virginia, a rock magnetic study was conducted with a focus on the Marcellus Shale. Vitrinite reflectance, fluid inclusions microthermometry and conodont alteration index data yield contradictory burial temperature within the range 150-250°C (302-482°F). The characterization of magnetite and pyrrhotite may be used as an index to track burial temperature around 200°C (392°F). Low-temperature and room-temperature magnetic measurements were performed in order to determine the magnetic assemblage. Three magnetic assemblages were identified that were stratigraphically distributed. The goethite and nanosized magnetite (Al) assemblage is mainly found in the Clinton Group-Oriskany Sandstone stratigraphic interval (Silurian-Lower Devonian). Nanosized fraction of magnetite and probably pyrrhotite (A3) assemblage essentially constitutes the Marcellus Shale-Chemung Formation sequence (Devonian). Microsized pyrrhotite is the typical mineral for A2 that is only identified near the Alleghenian structural front. Overall, the rare occurrence of micron pyrrhotite in our samples suggests that the study area has not experienced burial temperatures higher than 200°C (392°F).

The electrochemical reduction of GO was investigated in aqueous, at both acid and basic pH, and organic media, to identify the possible role of protons (H+) in the reduction mechanism of this material. The obtained rGO films were characterized by FTIR, electrochemical methods, Raman and XPS spectroscopy. Data showed that the reduction was more efficient in acid and basic media due to the presence of protons and the capacity of water that works as a proton donor, resulting in C/O ratios of 3.8 and 7.8, respectively. Mostly hydroxyl, epoxide and carbonyl moieties were removed. In a proton-free organic electrolyte, a C/O ratio of 1.8 was obtained for most of the samples; nevertheless, the graphitic carbon sp2 domains were restored to a large extent in the absence of H+. The characterization of the material showed that the presence of protons, during the electrochemical reduction, caused hydrogenation reactions, which targeted the graphitic domains in rGO and resulted in the loss of sp2 hybridization. The presence of such defects modified the electrochemical properties of the rGO films, where, despite of exhibiting higher C/O ratio, the films reduced in aqueous electrolytes displayed lower electron transfer (e.g. ferrocyanide redox-probe) than those reduced in organic electrolyte.

This work provides new insights in the field of applied photoelectro chemistry based on the use of nanoporous carbons as additives to tungsten oxide for the photooxidation of water under potential bias. Using a nanoporous carbon of low surface functionalization as additive to WO3 we have shown the dependence of the photochemical oxidation of water with the wavelength of the irradiation source. Photoelectrochemical responses obtained under monochromatic illumination show a significant increase in the incident photon-to-current conversion efficiency (IPCE) values for electrodes featuring up to 20 wt% carbon additive. Photoelectrochemical transient responses also show a sharp potential dependence, suggesting that the performance of the electrodes is strongly influenced by the carrier mobility and recombination losses. Despite the modest IPCE values of the W/NC electrodes (due to high bulk recombination and poor electron transport properties of the electrodes), our data shows that the incorporation of an optimal amount of nanoporous carbon additive to WO3 can enhance the carrier mobility of the semiconductor, without promoting additional recombination pathways or shadowing of the photoactive oxide., COA thanks the financial support of the European Research Council through a Consolidator Grant (ERC-CoG-648161-PHOROSOL) and the Spanish MINECO (grants CTM2014/56770-R, CTQ2013-48280-C3-3-R). VC and DJF kindly thank the UK Catalysis Hub for resources and support provided via the membership of the UK Catalysis Hub Consortium and funded by EPSRC (grants EP/ K014706/1, EP/K014668/1, EP/K014854/1, EP/K014714/1 and EP/M013219/1). AGB thanks her PhD fellowship (BES-2012-060410) and VC thanks the UK National Academy and the Royal Society by the support though the Newton International Fellows program.

We propose the use of siliceous diatomite as an antishrinkage additive for the synthesis of monolithic carbon aerogel electrodes with enhanced electrochemical response for capacitive deionization of NaCl solutions. Hybrid N- and Mn-doped carbon aerogels with improved electrical conductivity and wettability in the aqueous electrolyte are prepared by introducing modifications in the synthesis (carbon black and/or diatomite loading before the polymerization sol–gel polycondensation of the monomers, followed by manganese infiltration). The textural and morphological characterizations of the materials reveal that the presence of the additives does not impede the cross-linking of the monomers to form branched clusters and colloidal aggregates leading to a highly porous structure. Furthermore, the aerogel materials display an open macroporous network inherited by the diatomite, even after its lixiviation. As a result, the monolithic carbon aerogel electrodes present good electrochemical performance in terms of low polarization resistance, high capacitance, and fast electroadsorption., The authors are indebted to the MINECO (Contract IPT-2011-1450-310000 (ADECAR) and FEDER cofunding, and CTM2014-56770-R) for the financial support. We also thank the fruitful collaboration of Isolux Ingeniería, S.A., Fundación Imdea Energía and Proingesa.University of Cordoba thanks to SCAI and IUIQFN for technical support and Junta de Andalucía (FQM-288) for financial support.

International audience

Stable molecular hydrogen isotopes, D and T, are both scarce and essential in several energy, industrial, and large-scale fundamental research applications. Due to the chemical similarity of these isotopes, their extraction and purification from hydrogen has relied for decades on expensive and energy-demanding processes. However, factoring in the phenomenon of quantum sieving could provide a new route for these separations. In this work, we have explored how to separate hydrogen isotopes by adsorption taking these quantum effects into account. To this end, we have conducted adsorption measurements to test our deuterium model and performed a widespread computational screening over 210 pure-silica zeolites for D/H and T/H separations. Based on low-coverage adsorption properties, a reduced set of zeolites have been singled out and their performance in terms of adsorption capacity, selectivity, and dynamic behavior have been assessed. Overall, the BCT-type zeolite clearly stands out for highly selective separations of both D and T over H, achieving the highest reported selectivities at cryogenic temperatures. We also identified other interesting zeolites for the separation of hydrogen isotopes that offer an alternative way to tackle similar isotopic separations by an aimed selection or design of porous materials., This work was supported by the European Research Council through an ERC Starting Grant (ERC2011-StG-279520-RASPA). We thank C3UPO for the HPC support.

A glassy carbon electrode (GCE) was surface-modified with carbon quantum dots (CQDs) and applied for the effective enhancement of the electrochemical signal for dopamine and uric acid determination. CQDs were prepared from graphite by a green modification of the Hummers method. They were characterized by FTIR-ATR, XPS, solid-state NMR, fluorescence and Raman spectroscopies. TPD-MS analysis was applied to characterize the functionalization of the surface. The CQDs were assembled on the glassy carbon electrode by adsorption because of the large number of carboxy groups on their surface warrants effective adsorption. The modified GCE exhibits a sensitivity that is almost 10 times better than of the bare GCE. The lower limits of detection are 1.3 μM for uric acid and 2.7 μM for dopamine. Fil: Algarra, M.. Universidad de Málaga; España Fil: González Calabuig, A.. Universitat Autònoma de Barcelona; España Fil: Radotić, K.. University Of Belgrade; Serbia Fil: Mutavdzic, D.. University Of Belgrade; Serbia Fil: Ania, C.O.. Universite D'orleans; Francia Fil: Lazaro Martinez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Metabolismo del Fármaco. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Metabolismo del Fármaco; Argentina Fil: Jiménez Jiménez, J.. Universidad de Málaga; España Fil: Rodríguez Castellón, Enrique. Universidad de Málaga; España Fil: del Valle, M.. Universitat Autònoma de Barcelona; España

Activated carbons with different textural and chemical surface characteristics were synthesized from waste biomass and low rank coals, and furthermore used as a host matrix for cobalt species, varying the preparation and modification methods. The obtained activated carbons and modified samples were characterized by complex of various physicochemical methods, such as: low temperature physisorption of nitrogen, XRD, EPR, XPS, UV–Vis and TPR with hydrogen. Boehm method was applied for qualitative and quantitative determination of oxygen-containing groups on the carbon surface before and after cobalt deposition. The catalytic properties of cobalt modifications were tested in methanol decomposition. The dominant effect of activated carbon texture over the surface chemistry on the state and catalytic behavior of cobalt species was discussed., Financial support from Bulgarian Academy of Sciences and Bulgarian Ministry of Education (Projects DFNI-Е01/7/2012 and DFNI-E02/2/2014) is gratefully acknowledged.

A new hybrid Cu/rGO catalyst obtained by a thermal treatment of the composite of a copper-based MOF with graphite oxide exhibited a marked catalytic activity for oxygen reduction reaction (ORR) in an alkaline medium, high tolerance to methanol oxidation and superior long-term stability over 20 h. The unique architecture of the copper atoms in the 3D framework of the pristine MOF coupled with the excellent electron transfer properties of rGO lead to materials with a homogenous distribution of copper nanoparticles of specific chemistry assembled within the graphene sheets. Fast O2 adsorption and charge transfer owing to the strong interactions between copper atoms and graphite oxide resulted in highly stable and active Cu/rGO electrodes, compared to the carbonized MOF. The synergistic effect of copper and rGO in the composite leads to a superior ORR activity in terms of long-term stability and high current densities, close to the best performance reported for Pt and other metal-free electrocatalysts., COA thanks the Spanish MECD for her Salvador de Madariaga mobility action (CTM2011/23378 and PRX12/00290).

A novel set-up has been designed and used for synchrotron radiation X-ray high-resolution powder diffraction (SR-HRPD) in transmission geometry (spinning capillary) for in situ solid–gas reactions and processes in an isobaric and isothermal environment. The pressure and temperature of the sample are controlled from 10−3 to 1000 mbar and from 80 to 1000 K, respectively. To test the capacities of this novel experimental set-up, structure deformation in the porous material zeolitic imidazole framework (ZIF-8) by gas adsorption at cryogenic temperature has been studied under isothermal and isobaric conditions. Direct structure deformations by the adsorption of Ar and N2 gases have been observed in situ, demonstrating that this set-up is perfectly suitable for direct structural analysis under in operando conditions. The presented results prove the feasibility of this novel experimental station for the characterization in real time of solid–gas reactions and other solid–gas processes by SR-HRPD., The authors are grateful to the SpLine staff for their assistance. Financial support under grant PIE 201060E013 of the Consejo Superior de Investigaciones Científicas-CSIC and the Spanish Ministry of Economy and Competitiveness MINECO is also acknowledged.

This work reports a green and fast approach to the synthesis of nanoporous carbon materials based on the UV-assisted condensation of organic compounds as precursors. This new approach offers several improvements over the classical soft template and sol-gel routes for the synthesis of materials: versatility of organic precursors, shorter synthesis time, and ambient conditions. Owing to the specificity of the UV-assisted reactions mechanisms, organic compounds of varied chemical composition can be used as precursors in the preparation of nanoporous carbons with tuned porous features. The method consisted in the exposure of an aqueous solution of the organic precursors to UV light for 60 min at room temperature in the absence of a catalyst, allowing an outstanding shortening of the synthesis time compared to sol-gel routes. Furthermore, UV irradiation promoted the cross-linking of the polymer chains of precursors at room temperature, as opposed to classical methods that require an additional step at mild/high temperatures. By changing the chemistry of the organic compound used as precursor, it was possible to modulate the surface area (from 10 to 720 m2 g−1) and the porosity of the synthesized carbons within the micro-/mesopore range. The obtained carbons also presented varied morphology depending on the precursor, from dense aggregates to ordered hexagonal arrangements of nanometric dimensions., This study was supported by the European Research Council through a ERC-Consolidator Grant (648161-PHOROSOL) and the Spanish MINECO (grant CTM2014-56770-R).

International audience; Copepods are important suppliers of bioreactive compounds for marine bacteria through fecal pellet production, sloppy feeding, and the excretion of dissolved compounds. However, the interaction between copepods and bacteria in the marine environment is poorly understood. We determined the nitrogen and phosphorus compounds excreted by copepods fed with two natural size-fractionated diets (

Tesis doctoral presentada en la Universidad de Alicante. Diciembre de 2016., The main objective of this PhD thesis is explore the origin of the photoactivity of nanoporous carbons for evaluating their potential application in different fields of research covering their use as photocatalysts in the photooxidation of pollutants, as well as photoelectrodes for the photoelectrochemical oxidation of water, either by themselves or as additives coupled to a semiconductor in hybrid electrodes. The first stage of this study consisted mainly in investigating the photoactivity of various nanoporous carbons (in the absence of semiconductors) towards different reactions, aiming at linking their photochemical response with the nature of the carbon material in terms of porosity, surface chemistry, composition and structure. Exploring the photoassisted degradation of phenol adsorbed in the pore voids of several nanoporous carbons showed the beneficial effect of the tight confinement of phenol molecules in the porosity of the carbon material for an improved photoconversion. This demonstrated the outstanding role of the nanoconfinement to boost the fast interactions between the photogenerated charge carriers generated at the carbon material surface upon irradiation and the molecule adsorbed inside the nanopores. The irradiation wavelength was found a critical parameter for the phenol photooxidation reaction, with an optimum performance at low and high wavelengths, and a minimum photodegradation yield at ca. 400 nm for all the tested carbon materials. Another key factor strongly influencing the photoactivity of the nanoporous carbons was the surface functionalisation. When sulphur was incorporated to the carbon matrix (fixation of S-containing moieties), the light conversion in the phenol photooxidation became more efficient, and it was remarkably dependent on the nature of the S-groups. Further on, the analysis of photocurrent transients obtained by irradiating several nanoporous carbon electrodes exhibited different photoelectrochemical responses (either anodic or cathodic photocurrent) and transient shapes, thus demonstrating the distinct nature of the catalysed reaction occurring onto electrode/electrolyte interface. The second part of this research dealt with the synthesis, characterisation and evaluation of the performance of hybrid nanoporous carbon/semiconductor (i.e. WO3) electrodes towards the photoelectrochemical oxidation of water, aiming at exploring the role of nanoporous carbons as additives to a semiconductor. The presence of the nanoporous carbon additive had a remarkable effect on the photoelectrochemical response of the hybrid electrodes, in terms of conversion efficiency (IPCE). This is likely attributed to the improved separation of the photogenerated charge carriers in the presence of the carbon material. An optimal amount of carbon additive of ca. 20 wt.% was obtained for the best performing hybrid electrode, with a twofold IPCE compared to that obtained for a bare WO3 electrode. The effect of carbon additive was also found to be strongly dependent on the crystalline structure of the semiconductor, with different amounts of carbon additive needed for achieving the best performing photoanodes with monoclinic and hexagonal WO3.

The combined effect of resorcinol/catalyst (100≤R/C≤800) and resorcinol/water (0.04≤R/W≤0.13) molar ratio on the textural and capacitive properties of carbon aerogels with potential application for capacitive deionization has been evaluated. Activated and pyrolyzed aerogels were synthesized by the sol-gel polymerization of resorcinol-formaldehyde mixtures and dried in supercritical conditions. Data show that high R/C and R/W molar ratios lead to materials with large pores in the mesopore range, whereas the surface area and micropore volumes remain somewhat the same. The activation of the aerogels increased the differences in the specific surface and micropore volumes due to the development of microporosity. This effect was more remarkable for the samples with low R/C whatever the R/W ratio, indicating that the carbon aerogel obtained using high amounts of catalyst are more prone to be activated. Regarding the electrochemical features of the aerogels, low capacitance values were measured in aerogels combining low R/W and high R/C and reciprocally low R/C and high R/W molar ratios, due to their higher resistance. Polarization resistances were found to be slightly higher for the pyrolyzed than for activated aerogels, and followed a decreasing trend with the mesoporosity, indicating the outstanding contribution of the mesoporous network to provide a good kinetic response. The desalting capacity of monolithic aerogels showed a simultaneous dependence with the surface area and the resistivity of the electrodes, pointing out the importance of performing electrochemical measurements in adequate cell configurations (i.e., desalting units) upon the intended application., The authors are indebted to the Spanish MICINN (contract IPT-2011-1450-310000 (ADECAR) and CTM2014/56670-R) for the financial support. We also thank the fruitful collaboration of Isolux Ingeniería, S.A., Fundación Imdea Energia and Proingesa.

The Cameros Basin is a paleo-petroleum system formed in the north-eastern Iberian Peninsula. The basin formed during the Mesozoic Iberian Rift and was later inverted during the Alpine orogeny. Hydrothermal events took place during the post-extensional and inversion stages, producing an important impact on the thermal history of the basin. In order to determine the source rock of the petroleum system of the basin, organic matter characteristics, the petroleum generation potential and the maturity of the basin infill are determined by means of petrology and geochemical analyses. Several organic rich units of the stratigraphic record of the basin are potential source rocks for hydrocarbons generation, although their characteristics differ depending on their location. Organic matter content in the northern sector is scarce and limited to vitrinite, inertinite and solid bitumen particles. The residual total organic carbon (TOC < 1%), the low hydrocarbon potential (S2 < 0.3 mg HC/g rock, HI < 50 mg HC/g TOC), the mature to overmature thermal stages (%Ro from 1.7 to 4.6) and the presence of solid bitumen particles indicate that hydrocarbons have been already generated by these rocks. In contrast, the southern sector of the basin is characterized by abundant organic matter remnants (TOC from 2 to 17%) and immature to early oil-window thermal conditions (0.38–0.75%Ro), indicating a high hydrocarbon potential for these rocks (S2 from 11 to 123 mg HC/g and HI values from 23 to 715 mg HC/g TOC). The different evolution of the source rocks in the basin is the result of the combination of differential subsidence rates, which determine different thermal histories and of the circulation of hydrothermal fluids in the northern-central sector during the evolution of the basin., Funding for this research was provided by Spanish projects CGL2008- 01648/BTE, CGL2008-04916/BTE and CGL2011-22709, by the UCM-CM (Universidad Complutense Madrid Community) and by the INCAR-CSIC – Oviedo (Dr. Isabel Suárez-Ruiz). Thanks to Dr. Maria Isabel Benito Moreno for her help and advise in the field and in the revision process of this work.

Phenolic-formaldehyde resins aged at 85, 90 and 95 °C were used as ammonia adsorbents at dynamic conditions in dry and moist air. To avoid pressure drops 10% bentonite was added as a binder. The initial and hybrid materials (before and after ammonia adsorption) were extensively characterized from the point of view of their porosity and surface chemistry. The results showed that the addition of the binder had various effects on materials’ properties depending on the chemistry of their surface groups. When the phenolic acidic groups were predominant, the largest increase in surface acidity upon the addition of the binder was found. It was linked to the exfoliation of bentonite by polar moieties of the resins, which made acidic groups from aluminosilicate layers available for ammonia adsorption. On this sample, a relatively high amount of ammonia was strongly adsorbed in dry conditions. Insensitivity to moisture is a significant asset of ammonia adsorbents, This work was partially supported by the Spanish MINECO (CTM2014/56770-R). COA thanks her Salvador de Madariaga Mobility Action (PRX12/00290).

Soft-template approaches have been frequently applied for the preparation of porous carbons. Most of these processes proved highly effective for the preparation of mesoporous carbons with pore diameters below 10 nm but less explored has been the preparation of carbons with mesopores larger than 10 nm. The lack of syntheses providing large and well-interconnected mesopores is by no means a trivial issue because it limits the achievement of materials suitable for applications where pore surface accessibility is crucial – e.g. electrodes in supercapacitors or adsorbents in flow-through systems, among others. In this work, we have used deep eutectic solvents (DESs, a sort of ionic liquid, that are obtained by complexation of quaternary ammonium salts with hydrogen-bond donors) composed of resorcinol, urea and choline chloride for the preparation – via formaldehyde polycondensation and subsequent carbonization – of hierarchical porous carbons with micropores and large mesopores within the 10 to 20 nm range. The formation of large mesopores took place at the polycondensation stage via a spinodal decomposition process where some components forming the DES acted as precursors of the polymer phase, while some other ones were segregated into a polymer depleted phase. Thus, the ultimate dimension of the mesopores was controlled by the mass ratio between the segregated and condensed phases, and this mass ratio by the molar ratio of the components forming the original DES. We have finally demonstrated that carbons with larger mesopores exhibited better performance as electrodes in supercapacitor cells., The authors thank Spanish MINECO (grants MAT2012‐34811 and CTM2014‐56770‐R) for financial support. N. López‐Salas also acknowledges MINECO for a FPI research contract.

Deep eutectic solvents (DESs) composed of resorcinol, either 2-cyanophenol or 4-cyanophenol, and choline chloride were used for the synthesis of hierarchical nitrogen-doped carbon molecular sieves. Carbons were obtained with high conversions by polycondensation of resorcinol and either 2-cyanophenol or 4-cyanophenol with formaldehyde, and subsequent carbonization at 800 °C in nitrogen atmosphere. The nitrogen content was ca. 2.4 wt%, revealing an excellent nitrogen-doping efficiency for cyanophenol derivatives when used in the form of DES. The use of either 2-cyanophenol or 4-cyanophenol modified the contribution of quaternary-Nvalley groups in the resulting carbons, being larger in carbons coming from 4-cyanophenol than in those coming from 2-cyanophenol. The hierarchical porous structure was composed of micro-, meso- and macropores, and the diameter distribution of mesopores was also related to the use of either 2-cyanophenol or 4-cyanophenol. These structural and compositional differences were critical for the use of the resulting hierarchical nitrogen-doped carbons as efficient metal-free electrocatalysts. In particular, the carbons coming 4-cyanophenol proved particularly effective in the direct reduction of oxygen to OH− (H2O in acidic solution) through a four-electron (4e−) process with high catalytic activity and selectivity, and longer stability and stronger tolerance to crossover effects than platinum-based electrocatalysts.

We report the dependence of the photochemical activity of titania/carbon hybrid catalysts toward the degradation of phenol from solution using polychromatic light and filters. In all cases larger photooxidative efficiencies were obtained using light at 200 nm < λ < 600 nm. The incorporation of a carbon additive to TiO2 increased the photocatalytic performance regardless the illumination conditions, although, the effect was more pronounced at λ > 200 nm. The photocatalytic runs carried out with the nonporous carbon alone confirmed a certain level of intrinsic photoactivity under both irradiation conditions. Nevertheless, a clear deactivation was evident after 60 min of irradiation suggesting that the photoactive sites in the carbon are either consumed or deactivated in the course of the reaction. The composition of the catalyst and the illumination conditions also have a strong effect on the nature of the degradation intermediates, with a marked regioselectivity toward ortho-substitution at high energy photons and when the carbon component is added to the catalyst composition., The authors thank Cordex (Portugal) for kindly supplying sisal. The financial support of the pluriannual funding to CQB (UID/MULTI/00612/2013), and MINECO (CTM2014/56770-R, AIB2010-PT00209) is also acknowledged. MAA and ASM thank FCT for their PhD (SFRH/BD/71673/2010) and Post-Doc (SFRH/BPD/86693/2012) fellowships, respectively. RJC thanks PCTI Asturias Fondos Feder for her Severo Ochoa fellowship. The authors thank Dr. Matos for fruitful discussion.

Knowledge of the pore structure of carbon materials including micropores is crucial for applications such as double layer supercapacitors, gas separation, and other applications requiring high specific surface area materials. High surface area is always associated with fine micropores. The pore size distribution (PSD) of microporous carbons is usually evaluated from nitrogen adsorption isotherms measured at 77 K in the relative pressure range from 10−7 to 1. Due to the very slow gas diffusion into fine pores at cryogenic temperatures and low pressures, the adsorption measurements may be extremely time consuming and sometimes inaccurate when the adsorption equilibrium is difficult to achieve during the measurement. In this work, we discuss an approach in which the carbon PSD is calculated from the combined N2 and CO2 data measured in the pressure range from 1 to 760 Torr. Under such conditions, the diffusion into micropores is usually fast and equilibration times are short for both measurements. In the PSD calculations we use 2D-NLDFT models for carbons with heterogeneous surfaces (J. Jagiello and J.P. Olivier, Adsorption19, 2013, 777–783). We show that both isotherms can be fitted simultaneously with their corresponding models and as a result the unified PSD can be obtained., J.J. would like to thank Dr. Ani Nikova of Cabot Corporation for providing a sample of carbon BP280 and Dr. William Betz of Sigma–Aldrich Corporation for providing Supelco samples of carbon molecular sieves.

Highly micro-mesoporous carbon electrodes have been synthesized by the polycondensation of resorcinol-formaldehyde-melamine mixtures in the presence of a carbon conductive additive. The materials showed high surface functionalization (N- and O- groups) provided by the precursors. Despite the low amount used, the conductive additive had a marked effect on the porosity of the aerogels; for a given series, the carbon black loaded materials showed similar micropore volumes and a more developed mesoporosity than the pristine aerogels. Furthermore, the activation treatment under CO2 atmosphere led to an increase in the surface area along with a widening of the mesoporosity. The synthesized aerogels were explored as electrodes for the electro-assisted removal of sodium chloride from saline water. A desalting capacity of 7.3 mg/g was obtained for monolith electrodes of sample MRF-Act/CB, along with an excellent chemical stability upon charge and discharge at high polarization voltages. Such good electrochemical performance is due to the combination of an adequate pore network and surface functionalization with an enhanced electrical conductivity achieved upon the incorporation of the carbon black additive during the polycondensation of the aerogel precursors., The authors are indebted to the MICINN (Contract IPT-2011-1450-310000 (ADECAR), and CTM2011/23378) for the financial support. We also thank the fruitful collaboration of Isolux Ingeniería, S.A., Fundación Imdea Energia and Proingesa. University of Córdoba thanks to SCAI for technical and FEDER and Junta de Andalucía (FQM-288) for financial supports.

The sol–gel polymerization of resorcinol/formaldehyde mixtures to obtain porous gels is typically a long process performed throughout several days. In this work, we have explored an experimental approach to reduce the time necessary to obtain porous gels based on mild polymerization conditions and direct drying. We have analyzed the effects of the temperature and time of the gelation/aging step on the porosity of the gels, as well as the impact on the overall energetic cost of the process. Data have shown that well-developed micro–mesoporous architectures can be obtained within less than a day. The temperature of the gelation/aging step mainly affects the mesopore network, whereas the microporosity is determined by the composition of the precursor’s mixture. The exclusion of the solvent exchange step yields soft mechanically fragile porous gels with structural limitations upon carbonization at high temperature in inert atmosphere, due to the surface tensions applied to the backbone during the evolution of volatiles. The mesopore structure lost during carbonization is not recovered upon activation in CO2 atmosphere, but it is preserved upon chemical activation in K2CO3 and the resulting gel exhibits a bimodal micro–mesoporous distribution. Furthermore, the energy savings of this route are similar to those obtained using microwave-heating in terms of grams of xerogel per kilowatt hour of energy consumed for similar textural properties. The correlation between the energy power consumed and the textural parameters is a useful tool to optimize the synthesis., The authors thank the financial support of the Spanish MINECO (grant CTM2011/023378) and Fondos Feder PCTI Asturias (grant PC10-002). EDIP and RJC are grateful to CONACyT and PCTI Asturias for the mobility grant (290674) and Severo Ochoa fellowship, respectively. COA acknowledges Dr. Jacek Jagiello for the fruitful discussion on 2D-NLDFT-HS model.

N-doped carbon aerogels were synthesized by the polycondensation of resorcinol–formaldehyde–melamine mixtures. The prepolymerization of the precursors was determinant for the preparation of meso/macroporous aerogels with varied nitrogen content, regardless the solution pH and M/R molar ratio. The effect was more pronounced at pH 6, as the hydrogels prepared by the one-step route displayed essentially a microporous character, as opposed to the mesoporous network after prepolymerization. The prepolymerized carbon aerogels presented large capacitance values due to the optimum balance between pore structure, improved wettability and low polarization resistance for the highly doped materials. Salt deionization capacity revealed the importance of the macropore structure in the monolithic configuration of the aerogels for a fast electrosorption of ions., The authors are indebted to the MINECO – Spain (Contract IPT-2011-1450-310000 (ADECAR), and CTM2011/23378) for the financial support. We also thank the fruitful collaboration of Isolux Ingeniería, S.A., Fundación Imdea Energia and Proingesa. University of Córdoba thanks to SCAI for technical support and Junta de Andalucía (FQM-288) for financial support.

We have explored the role of the physicohemical properties of carbon materials as additives to bismuth tungstate on its structure, optical properties, and photocatalytic activity for the degradation of rhodamine B under visible light. For this purpose, C/Bi2WO6 hybrid composites were prepared following two different routes: (i) physical mixture of the catalyst components, and (ii) one-pot hydrothermal synthesis of the semiconductor in the presence of the carbon additive. Three carbons with different properties were selected as additives: biomass-derived activated carbon, carbon nanotubes and carbon spheres obtained from polysaccharides. Data has shown the outstanding role of the acidic/basic nature of the carbon additive, and of the synthetic method on the photocatalytic performance of the resulting composites. For a given additive, the degradation rate of RhB is greatly improved for the catalysts prepared through a one-step hydrothermal synthesis, where there is low shielding effect of the carbon matrix. Carbon additives of acidic nature boost the surface acidity of the hybrid photocatalyst, thereby enhancing the photodegradation of RhB under visible light via a coupled mechanism (photosensitization, semiconductor photocatalysis and carbon-photon mediated reactions)., The authors thank the financial support of MINECO (grants CTM2011/23378 and CTQ2011/26617) and PCTI Asturias (Fondos Feder 2007-2013, grant PC10-002). RJC thanks PCTI Asturias for her Severo Ochoa fellowship

We showed the effect of surface oxidation on the conversion of light into a chemical reaction in the confined pore space of nanoporous carbons. The photoactivity of carbons is caused by the combination of high porosity and the presence of photoreactive sites that favor the splitting of the exciton inside the pores, which boosts its efficient use in chemical reactions. The incorporation of O-containing groups in the carbon matrix decreased the photoconversion inside the pores, although values were higher than those attained in solution. This is attributed to the lower stabilization of the exciton through the delocalization within the conjugated sp2 network of the basal planes because of the electron-withdrawing effect of the O-containing groups. The photochemical conversion of light inside the pores is very sensitive to the acidic/basic nature of the O-containing groups of the carbon matrix, and can be enhanced by balancing the surface composition, porosity, and electronic mobility., The financial support of the Spanish MINECO (grant CTM2014- 56770-R) is acknowledged.

The Cameros Basin (North Spain) is a Late Jurassic‐Early Cretaceous extensional basin, which was inverted during the Cenozoic. It underwent a remarkable thermal evolution, as indicated by the record of anomalous high temperatures in its deposits. In this study, the subsidence and thermal history of the basin is reconstructed, using subsidence analysis and 2D thermal modelling. Tectonic subsidence curves provide evidence of the occurrence of two rapid subsidence phases during the syn‐extensional stage. In the first phase (Tithonian‐Early Berriasian), the largest accommodation space was formed in the central sector of the basin, whereas in the second (Early Barremian‐Early Albian), it was formed in the northern sector. These rapid subsidence phases could correspond to relevant tectonic events affecting the Iberian Plate at that time. By distinguishing between the initial and thermal subsidence and defining their relative magnitudes, Royden's (1986) method was used to estimate the heat flow at the end of the extensional stage. A maximum heat flow of 60–65 mW/m2 is estimated, implying only a minor thermal disturbance associated with extension. In contrast with these data, very high vitrinite reflectance, anomalously distributed in some case with respect to the typical depth‐vitrinite reflectance relation, was measured in the central‐northern sector of the basin. Burial and thermal data are used to construct a 2D thermal basin model, to elucidate the role of the processes involved in sediment heating. Calibration of the thermal model with the vitrinite reflectance (%Ro) and fluid inclusion (FI) data indicates that in the central and northern sectors of the basin, an extra heat source, other than a typical rift, is required to explain the observed thermal anomalies. The distribution of the %Ro and FI values in these sectors suggests that the high temperatures and their distribution are related to the circulation of hot fluids. Hot fluids were attributed to the hydrothermal metamorphic events affecting the area during the early post‐extensional and inversion stages of the basin., Funding for this research was provided by Spanish Government Projects CGL2008‐ 01648/BTE, CGL2008‐04916/BTE, CGL2011‐22709 and the Consolider‐Ingenio 2010 programme, under CSD 2006‐0004 “Topo‐Iberia”, by the UCM‐CM (Universidad Complutense Madrid Community) and by the INCAR‐CSIC – Oviedo.

A simple modification of the sol–gel polymerization of resorcinol–formaldehyde mixtures allowed the preparation route of homogeneously dispersed carbon black-activated carbon aerogel composites with high pore volumes and improved electrical conductivity. These materials showed good performance as electrodes for the electro-assisted removal of sodium chloride from saline water using high voltages. Besides the effect of the carbon black additive, we have investigated the influence of resorcinol–water ratio on the textural and electrochemical properties of the resulting materials. Data has shown a slight dependence on the structural order of the aerogels with the R/W ratio, regardless the incorporation of the conductive additive. The effect of the carbon black on the textural features was also negligible, due to the low amount incorporated. Nonetheless, the samples showed higher capacitance values for the removal of ions from solution, due to the enhanced conductivity provided by the carbon black, being the effect more evident for the materials prepared using a low R/W ratio., The authors are indebted to the MICINN (Contract IPT-2011-1450-310000 (ADECAR), and CTM2011/23378) for the financial support. We also thank the fruitful collaboration of Isolux Ingeniería, S.A., Fundación Imdea Energia and Proingesa. University of Córdoba thanks to SCAI and IUIQFN for technical support and Junta de Andalucía (FQM-288) for financial support.

We report on a facile and rapid microwave-assisted method for preparing a sodium–cadmium metal–organic framework (having coordinatively unsaturated sodium ions) that considerably shortens the conventional synthesis time from 5 days to 1 hour. The obtained (Na,Cd)-MOF showed an excellent volumetric CO2 adsorption capacity (5.2 mmol cm−3 at 298 K and 1 bar) and better CO2 adsorption properties than those shown by the same metal–organic framework when synthesized following a more conventional procedure. Moreover, the newly prepared material was found to display high selectivity for adsorption of carbon dioxide over nitrogen, and good regenerability and stability during repeated CO2 adsorption–desorption cycles, which are the required properties for any adsorbent intended for carbon dioxide capture and sequestration (CSS) from the post-combustion flue gas of fossil fuelled power stations., The Spanish Ministerio de Economía y Competitividad (MINECO) and the European Funds for Regional Development (FEDER) are gratefully acknowledged for financial support through Project CTQ2013-47461-R. Financial support from Programa Pont la Caixa per a grups de recerca de la UIB is also acknowledged. C.P. acknowledges the Spanish Ministerio de Educación y Ciencia (pre-doctoral fellowship).

International audience; The character of the coal in Tomago and Greta coal measures are similar to other coals from the Sydney Coal Basin, with variation from vitrinite-rich to inertinite-rich coal. A type III organic matter (OM) linked to continental higher plants and a perhydrous type III similar to type II were found by Rock-Eval analysis. The coexistence of inertinite with algae (Botryococcus) in the Greta coals explains the high HI in the perhydrous type. The Gangamopteris flora that is reported in the Greta coal measures, grew after plants in a taiga like the recent birch forests in Russia (Retallack, 1980). The Glossopteris flora that is reported in the Tomago coal measures, grew in a swamp forest. Based upon the botanic zonation, this flora was located in the cold temperate biome that was located in Gondwanaland, except for Antarctica which was in the glacial biome. Diterpane analysis results reveal alternation of wet and dry periods existed during the deposition of Lewis coals in the Greta coal measures during the Kungurian, and an increase of dryness is noted from Upper Donaldson to Beresfield in the Tomago coal measures during the Capitanian. Based on analysis of aromatics and diterpanes, the same periods of dryness and wetness alternate during the coal deposition in the Sydney Coal Basin. These climatic changes correspond to high frequency cycles (

We have analyzed the effects of CO2 activation on the porosity of ultrahigh pore volume carbon aerogels. Data obtained from the new 2D-NLDFT-HS model for carbons has been compared to the results of conventional methods (BJH, t-plot, DR); all the models were applied to the desorption branch of the isotherms. Physical activation of the carbon aerogel at different burn-off degrees resulted in materials showing increasing volume of micropores and alteration of mesopore structure. The later effect manifested itself by a characteristic inflection in the desorption branch of the nitrogen isotherm at high relative pressures. Such curvatures are attributed to a non uniform activation of the carbon matrix with CO2 that in some parts carves the surface of the precursor deeper than in others, creating bimodal/multimodal pore size distributions. The different methods applied for the assessment of the textural properties of the aerogels with ultrahigh micro-/mesoporosity showed excellent agreement in terms of pore volumes, surface areas and average pore size., The authors thank the financial support of the Spanish MINECO (grant CTM2011/02338). REFERENCES