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Amphiphilic carbon nitride (g-C3N4) was decorated onto reduced graphene oxide (rGO) to obtain rGO-g-C3N4 composites as excellent adsorbents for the removal of aromatic organic compounds from industrial wastewater. The as obtained rGO-g-C3N4 composites are effective adsorbents for organic compounds due to the amphiphilic g-C3N4. We propose a new adsorption model using an amphiphilic additive which can enhance the water accessibility and hydrophobic interactions between rGO with organic compounds in aqueous media. Where, even water-soluble organic molecules like rhodamine B (RhB) have a high adsorption capability for the rGO-g-C3N4 (520 mg g−1). Molecular dynamics simulations were used to investigate the interactions between RhB and rGO-g-C3N4 and indicated that amphiphilic g-C3N4 accelerates the adsorption process. In addition, the amphipathic adsorption approach is enhanced as the salinity of water increases, which can offer great operational flexibility and versatility. This research demonstrates that the highly efficient interactions between aromatic organic molecules and amphiphilic carbon-based nanomaterials can be used for practical applications.

In recent decades, the demand for biomedical imaging tools has grown very rapidly as a key feature for biomedical research and diagnostic applications. Particularly, fluorescence imaging has gained increased attention as a non-invasive, inexpensive technique that allows real-time imaging. However, tissue auto-fluorescence under external illumination, together with a weak tissue penetration of low wavelength excitation light, largely restricts the application of the technique. Accordingly, new types of fluorescent labels are currently being investigated and, in this search, phosphorescent nanoparticles promise great potential, as they combine the interesting size-dependent properties of nanoscale materials with a long-lasting phosphorescence-type emission that allows optical imaging well after excitation (so avoiding autofluorescence). In this work, core-shell structures consisting of SrAlO:Eu,Dy luminescent cores encapsulated within a biocompatible silica shell were prepared, showing a green persistent phosphorescence with an afterglow time of more than 1000 s. A high-energy ball milling procedure was used to reduce the size of the starting phosphors to a size suitable for cellular uptake, while the silica coating was produced by a reverse micelle methodology that eventually allows the excitation and emission light to pass efficiently through the shell. Confocal fluorescence microscopy using HeLa cancer cells confirmed the potential of the all-ceramic composites produced as feasible labels for in vitro optical imaging.

We report on the design and testing of new graphite and graphene oxide‐based extended π‐conjugated synthetic scaffolds for applications in sustainable chemistry transformations. Nanoparticle‐functionalised carbonaceous catalysts for new Fischer Tropsch and Reverse GasWater Shift (RGWS) transformations were prepared: functional graphene oxides emerged from graphite powders via an adapted Hummer's method and subsequently impregnated with uniform‐sized nanoparticles. Then the resulting nanomaterials were imaged by TEM, SEM, EDX, AFM and characterised by IR, XPS and Raman spectroscopies prior to incorporation of Pd(II) promoters and further microscopic and spectroscopic analysis. Newly synthesised 2D and 3D layered nanostructures incorporating carbon‐supported iron oxide nanoparticulate pre‐catalysts were tested, upon hydrogen reduction in situ, for the conversion of CO2 to CO as well as for the selective formation of CH4 and longer chain hydrocarbons. The reduction reaction was also carried out and the catalytic species isolated and fully characterised. The catalytic activity of a graphene oxide‐supported iron oxide pre‐catalyst converted CO2 into hydrocarbons at different temperatures (305, 335, 370 and 405 °C), and its activity compared well with that of the analogues supported on graphite oxide, the 3‐dimensional material precursor to the graphene oxide. Investigation into the use of graphene oxide as a framework for catalysis showed that it has promising activity with respect to reverse gas water shift (RWGS) reaction of CO2 to CO, even at the low levels of catalyst used and under the rather mild conditions employed at atmospheric pressure. Whilst the γ‐Fe2O3 decorated graphene oxide‐based pre‐catalyst displays fairly constant activity up to 405 °C, it was found by GC‐MS analysis to be unstable with respect to decomposition at higher temperatures. The addition of palladium as a promoter increased the activity of the iron functionalised graphite oxide in the RWGS. The activity of graphene oxide supported catalysts was found to be enhanced with respect to that of iron‐functionalised graphite oxide with, or without palladium as a promoter, and comparable to that of Fe@carbon nanotube‐based systems tested under analogous conditions. These results display a significant step forward for the catalytic activity estimations for the iron functionalised and rapidly processable and scalable graphene oxide. The hereby investigated phenomena are of particular relevance for the understanding of the intimate surface morphologies and the potential role of non‐covalent interactions in the iron oxide‐graphene oxide networks, which could inform the design of nano‐materials with performance in future sustainable catalysis applications.

[EN] The gallium-68 radiolabelling of new functional graphene oxide composites is reported herein along with kinetic stability investigations of the radio-nanohybrids under different environments and insights into their surface characteristics by SEM and XPS. The present work highlights the potential of graphene oxides as nanocarriers for small molecules such as bis (thiosemicarbazonato) complexes to act as multifunctional platforms for rapid and effective radioimaging agent incorporation., The S. I. P. group thanks the Centre for Doctoral Training in Sustainable Chemical Technologies (EP/L016354/1). SIP also acknowledges the EU funding through the ERC for the Consolidator Grant O2SENSE (617107, 2014–2020). The authors thank EPSRC National Service for Mass Spectrometry at Swansea and for data collection. We thank Professor Stan Botchway for training in confocal fluorescence microscopy and Professor Jon Dilworth for helpful discussions in the radiochemistry of bis (thiosemicarbazones). The EOA group acknowledges support from Imperial College NIHR Biomedical Research Centre, Cancer Research UK (C2536/A16584) and the UK Medical Research Council (MR/J007986/1). D. G. C. also acknowledges the Fundación General CSIC (ComFuturo Program) for the financial support and F. J. P. the Spanish Ministry of Economy and Competitiveness (MINECO) (MAT2016-80394-R).

[EN] In this study, the photocatalytic activity in hydrogen production of a TiO catalyst with hierarchical structure and microsphere morphology was tested. This catalyst was synthesised by hydrolysis and condensation processes from a Ti(OBut) precursor and calcined at 150 °C, 400 °C and 630 °C. Hydrogen production of the subsequent photocatalysts rose by two and three orders of magnitude after the incorporation of Au or Pt particles by photodeposition. The microspheres with and without metal modification were characterised by scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), Raman, Brunauer–Emmett–Teller (BET) surface area, Fourier transform infrared spectroscopy (FTIR) and diffuse reflectance measurements. The highest production rates were obtained for the metal-modified photocatalysts calcined at 400 °C. Hydrogen production increased with Au loading, attaining a rate of 1118 μmol·h for the 1.5 wt% Au photocatalyst. However, the highest production rate in the case of Pt was attained with just 0.27 wt% and was almost twice as high as that obtained with Au, 2125 μmol·h. When compared with previous studies by our team under the same conditions, this high production rate, obtained with a very low Pt loading, was only exceeded by the reference Aeroxide P25 TiO catalyst with a Pt loading greater than 1.5 wt%., This work was supported by the Spanish Ministry of Science and Innovation through the project IPT-120000-2010-033(GESHTOS). We would also like to thank the Spanish Ministry of Science and Innovation for the UNLP10-3E-726 infra-structure, co-financed with ERDF funds. T. Jardiel alsoacknowledges the financial support of the MAT2014-59210-JIN project of MINECO. M. Nereida Suárez would also like to thankthe University of Las Palmas de Gran Canaria for its fundingthough the PhD Grant Program.

Existing fluorescent labels used in life sciences are based on organic compounds with limited lifetime or on quantum dots which are either expensive or toxic and have low kinetic stability in biological environments. To address these challenges, luminescent nanomaterials have been conceived as hierarchical, core-shell structures with spherical morphology and highly controlled dimensions. These tailor-made nanophosphors incorporate Ln:YVO4 nanoparticles (Ln = Eu(III) and Er(III)) as 50 nm cores and display intense and narrow emission maxima centered at ∼565 nm. These cores can be encapsulated in silica shells with highly controlled dimensions as well as functionalized with chitosan or PEG5000 to reduce nonspecific interactions with biomolecules in living cells. Confocal fluorescence microscopy in living prostate cancer cells confirmed the potential of these platforms to overcome the disadvantages of commercial fluorophores and their feasibility as labels for multiplexing, biosensing, and imaging in life science assays.

Metallic nanoparticles have been a matter of intense exploration within the last decade due to their potential to change the face of the medical world through their role as ‘nanotheranostics’. Their envisaged capacity to act as synthetic platforms for a multimodal imaging approach to diagnosis and treatment of degenerative diseases, including cancer, remains a matter of lively debate. Certain synthetic metal-based nanomaterials, e.g. gold and iron oxide nanoparticles, are already in clinical use or under advanced preclinical investigations following in vitro and in vivo preclinical imaging success. We surveyed the recent publications landscape including those reported metallic nanoparticles having established applications in vivo, as well as some of the new metallic nanoparticles which, despite their potential as cancer nanodiagnostics, are currently awaiting in vivo evaluation. The objective of this review is to highlight the current metallic nanoparticles and/or alloys as well as their derivatives with multimodal imaging potential, focusing on their chemistry as a springboard to discussing their role in the future of nanomedicines design. We also highlight here some of the fundamentals of molecular and nano-imaging techniques of relevance to the metal-based colloids, alloys and metallic nanoparticles discerning their future prospects as cancer nanodiagnostics. The current approaches for metallic and alloy surface derivatisation, aiming to achieve functional and biocompatible materials for multimodal bioimaging applications, are discussed in order to bring about some new perspectives on the efficiency of metallic nanoparticles as synthetic scaffolds for imaging probe design and forecast their future use in medical imaging techniques (optical, CT, PET, SPECT and MRI).

Highly homogeneous gallium doped ZnO assembled nanostructures comprised by thin hexagonal platelets showing a striking preferred orientation along the ab plane have been obtained by an ultra-fast and eco-friendly microwave-assisted hydrothermal synthesis method. Although the incorporation of gallium into the ZnO lattice is found to be relatively low, namely ≤1 mol.%, the gallium nitrate addition plays a key role in the size and morphology of the obtained ZnO nanostructures. The observed morphology is attributed to the selective adsorption of the gallium species on the basal planes of ZnO, which inhibits the growth along the ± [0001] direction. Additionally, the optical band-gap and the fluorescence emission are modified upon gallium addition. The observed changes in the optical properties are ascribed to both the decreased crystal size and to the gallium incorporation into the ZnO structure, which lead to the modification in the energy levels., This work has been conducted within the MAT2013-40722-R, MAT2014-59210-JIN and MAT2016-80182-R projects. This work was also conducted in the frame of “Grupo de Propiedades Ópticas, Eléctricas y Magnéticas y sus Aplicaciones”, (UPM), Unidad Asociada al Instituto de Cerámica y Vidrio (CSIC).

[EN] The metastability impediment which usually prevents the obtaining of a phase-pure BiFeO3 material can be dramatically stressed when taking the system to the thin film configuration. In order to preserve the stoichiometry, the films need to be processed at low temperatures and hence the solid-state diffusion processes which usually govern the microstructural evolution in bulk cannot be expected to also rule the development of the functional films. All these circumstances were presumed when exploring the possibilities of an aqueous solution–gel process plus spin-coating deposition method to reproduce, in thin film dimensions, the excellent multiferroic properties that have been previously observed with an optimized rare-earth and Ti4+-codoped BiFeO3 bulk composition. The experiments indicate high reliability for the tested methodology, allowing for the obtaining of homogeneous dense films at temperatures as low as 600 1C and with a tunable multiferroic response depending on the formulated rare-earth (Sm or Nd). Thorough structural characterization of the films reveals that despite the low temperature processing restrictions, effective microstructural control is achieved at the nanoscale, which is attributed to effective retention (pinning) of the dopants inside the perovskite structure of BiFeO3., his work was supported by the Spanish Ministry of Science, Innovation and Universities (MICINN) under projects MAT2016-80182-R, MAT2017-87134-c2-2-R and partially by the project MAT2016-76851-R. It was also supported by the Research Foundation Flanders (FWO-Vlaanderen), project number G039414N. Dr T. Jardiel acknowledges the European Science Foundation (ESF) and the Ramon y Cajal Program of MICINN for the financial support. Work by Dr Calatayud was also supported by Fundación General CSIC (COMFUTURO Program). We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

[EN] Anatase TiO2 has become a material of great interest for photocatalytic production of hydrogen, environmental purification and solar energy conversion. Among the key parameters boosting the photocatalytic efficiency of the anatase nanoparticles, an increased light absorption to expand its optical response to the visible region, together with an improved charge separation of the photo- generated electrons and holes, can be enumerated. In this work, yellow-coloured, single-phase anatase nanoparticles have been obtained using a simple two-step solvothermal routine which requires no external addition of dopants, nor the use of a harassing/aggressive synthesis atmosphere. The obtained powders display a lowered bandgap (, This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through MAT2014-59210-JIN, MAT2016-80182-R, MAT2016-80394-R and CSIC 201760E012 projects. Dr T Jardiel acknowledges the European Science Foundation (ESF) and the Ramon y Cajal Program of MICINN for the financial support. Dr D G Calatayud also acknowledges the Fundación General CSIC (ComFuturo Program) for the financial support.

[EN] Nowadays, there are no targeted therapeutic modalities for triple negative breast cancer (TNBC). This disease is associated with poor prognosis and worst clinical outcome because of the aggressive nature of the tumor, delayed diagnosis, and non-specific symptoms in the early stages. Therefore, identification of novel specific TNBC serum biomarkers for screening and therapeutic purposes remains an urgent clinical requirement. New user-friendly and cheap methods for biomarker identification are needed, and nanotechnology offers new opportunities. When dispersed in blood, nanoparticles (NPs) are covered by a protein shell termed ¿protein corona¿ (PC). While alterations in protein patterns are challeging to detect by conventional blood analyses, PC acts as a ¿nano-concentrator¿ of serum proteins with affinity for NPs¿ surface. So, the characterization of PC could allow the detection of otherwise undetectable changes in protein concentration at an early stage of the disease or after chemotherapy or surgery. To explore this research idea, serum samples from 8 triple negative breast cancer (TNBC) patients and 8 patients without malignancy were allowed to interact with gold nanoparticles (AuNPs: 10.02¿±¿0.91¿nm), silver nanoparticles (AgNPs: 9.73¿±¿1.70¿nm) and magnetic nanoparticles (MNPs: (9.30¿±¿0.67¿nm). Here, in order to identify biomarker candidates in serum of TNBC patients, these nanomaterials were combined with electrophoretic separation (SDS-PAGE) to performed qualitative and quantitative comparisons of the serum proteomes of TNBC patients (n = 8) and healthy controls (n = 8) by liquid chromatography tandem-mass spectrometry (LC-MS/MS) analysis. The results were validated through a sequential window acquisition of all theoretical mass spectra (SWATH) analysis, performed in total serum samples (patients and controls) using this approach as a multiple reaction monitoring (MRM) analysis. Significance It is well known that several proteins presented in human serum are important biomarkers for the diagnosis or prognosis of different diseases, as triple negative breast cancer (TNBC). Determining how nanomaterials as gold nanoparticles (AuNPs: 10.02¿±¿0.91¿nm), silver nanoparticles (AgNPs: 9.73¿±¿1.70¿nm) and magnetic nanoparticles (MNPs: (9.30¿±¿0.67¿nm) interact with human serum will assist not only in understanding their effects on the biological system (biocompability and toxicity), but also to obtain information for developing novel nanomaterials with high specificity and selectivity towards proteins with an important biological function (prognostic and diagnostic protein biomarkers)., All authors acknowledge Miguel Servet I Programme (CP16/00139) from the “Instituto de Salud Carlos III” (Plan Estatal de I+D+i 2013-2016 and European Development Regional Fund) of the Spanish Ministry of Science, Innovation and Universities. A. Castro López and M.P. Chantada-Vázquez contributed equally to this work.

We report on the design and testing of new graphite and graphene oxide‐based extended π‐conjugated synthetic scaffolds for applications in sustainable chemistry transformations. Nanoparticle‐functionalised carbonaceous catalysts for new Fischer Tropsch and Reverse GasWater Shift (RGWS) transformations were prepared: functional graphene oxides emerged from graphite powders via an adapted Hummer's method and subsequently impregnated with uniform‐sized nanoparticles. Then the resulting nanomaterials were imaged by TEM, SEM, EDX, AFM and characterised by IR, XPS and Raman spectroscopies prior to incorporation of Pd(II) promoters and further microscopic and spectroscopic analysis. Newly synthesised 2D and 3D layered nanostructures incorporating carbon‐supported iron oxide nanoparticulate pre‐catalysts were tested, upon hydrogen reduction in situ, for the conversion of CO2 to CO as well as for the selective formation of CH4 and longer chain hydrocarbons. The reduction reaction was also carried out and the catalytic species isolated and fully characterised. The catalytic activity of a graphene oxide‐supported iron oxide pre‐catalyst converted CO2 into hydrocarbons at different temperatures (305, 335, 370 and 405 °C), and its activity compared well with that of the analogues supported on graphite oxide, the 3‐dimensional material precursor to the graphene oxide. Investigation into the use of graphene oxide as a framework for catalysis showed that it has promising activity with respect to reverse gas water shift (RWGS) reaction of CO2 to CO, even at the low levels of catalyst used and under the rather mild conditions employed at atmospheric pressure. Whilst the γ‐Fe2O3 decorated graphene oxide‐based pre‐catalyst displays fairly constant activity up to 405 °C, it was found by GC‐MS analysis to be unstable with respect to decomposition at higher temperatures. The addition of palladium as a promoter increased the activity of the iron functionalised graphite oxide in the RWGS. The activity of graphene oxide supported catalysts was found to be enhanced with respect to that of iron‐functionalised graphite oxide with, or without palladium as a promoter, and comparable to that of Fe@carbon nanotube‐based systems tested under analogous conditions. These results display a significant step forward for the catalytic activity estimations for the iron functionalised and rapidly processable and scalable graphene oxide. The hereby investigated phenomena are of particular relevance for the understanding of the intimate surface morphologies and the potential role of non‐covalent interactions in the iron oxide‐graphene oxide networks, which could inform the design of nano‐materials with performance in future sustainable catalysis applications., New functional two‐dimensional (2D) and three‐dimensional (3D) nanomaterials relevant for sustainable chemistry applications have been designed and tested. This work is of relevance to enhancing our understanding of the role of supramolecular aggregation on nanotechnology and on optimised designs for future materials for energy conversion/storage as a basis for the reverse gas water shift reaction and Fischer Tropsch chemistry.

Three‐dimensional fluorescent graphene frameworks with controlled porous morphologies are of significant importance for practical applications reliant on controlled structural and electronic properties, such as organic electronics and photochemistry. Here we report a synthetically accessible approach concerning directed aromatic stacking interactions to give rise to new fluorogenic 3D frameworks with tuneable porosities achieved through molecular variations. The binding interactions between the graphene‐like domains present in the in situ‐formed reduced graphene oxide (rGO) with functional porphyrin molecules lead to new hybrids via an unprecedented solvothermal reaction. Functional free‐base porphyrins featuring perfluorinated aryl groups or hexyl chains at their meso‐ and β‐positions were employed in turn to act as directing entities for the assembly of new graphene‐based and foam‐like frameworks and of their corresponding coronene‐based hybrids. Investigations in the dispersed phase and in thin‐film by XPS, SEM and FLIM shed light onto the nature of the aromatic stacking within functional rGO frameworks (denoted rGOFs) which was then modelled semi‐empirically and by DFT calculations. The pore sizes of the new emerging reduced graphene oxide hybrids are tuneable at the molecular level and mediated by the bonding forces with the functional porphyrins acting as the “molecular glue”. Single crystal X‐ray crystallography described the stacking of a perfluorinated porphyrin with coronene, which can be employed as a molecular model for understanding the local aromatic stacking order and charge transfer interactions within these rGOFs for the first time. This opens up a new route to controllable 3D framework morphologies and pore size from the Ångstrom to the micrometre scale. Theoretical modelling showed that the porosity of these materials is mainly due to the controlled inter‐planar distance between the rGO, coronene or graphene sheets. The host‐guest chemistry involves the porphyrins acting as guests held through π‐π stacking, as demonstrated by XPS. The objective of this study is also to shed light into the fundamental localised electronic and energy transfer properties in these new molecularly engineered porous and fluorogenic architectures, aiming in turn to understand how functional porphyrins may exert stacking control over the notoriously disordered local structure present in porous reduced graphene oxide fragments. By tuning the porosity and the distance between the graphene sheets using aromatic stacking with porphyrins, it is also possible to tune the electronic structure of the final nanohybrid material, as indicated by FLIM experiments on thin films. Such nanohybrids with highly controlled pores dimensions and morphologies open the way to new design and assembly of storage devices and applications incorporating π‐conjugated molecules and materials and their π‐stacks may be relevant towards selective separation membranes, water purification and biosensing applications., By introducing a panel of functional porphyrin molecules, new 3D hierarchical structures incorporating reduced graphene oxide can be achieved. The pore size of the framework can be finely tuned and reduced to a sub‐micron scale for the first time by careful selection of the porphyrin. Experimental and theoretical studies proposed that the pore size diminishing was due to strong local interactions between the designed porphyrin and rGO, mediated by donor‐acceptor interactions, which are maintained in the solution and in thin film.

Titanium substitution can improve the multiferroic properties of bismuth ferrite materials, albeit the structural changes that this dopant produces in the perovskite structure of BiFeO3 are still not well understood. Due to its high sensitivity, Raman spectroscopy can be a useful tool for trailing the dopant incorporation. In this work, we study the Raman spectra of undoped and Ti4+-doped BiFeO3 ceramics that also contain small amounts of secondary phases – as it is usual for materials of this system. The micro-Raman study together with a rigorous derivative analysis of the experimental Raman spectra recorded at low temperature (73 K) enables, for the first time, the identification of the Raman bands associated with the BiFeO3 phase together with those belonging to the minor secondary phases. The comparison between the Raman spectra of the undoped and the Ti4+-doped materials indicates that some of the titanium added to the composition interacts with the secondary phases while only a partial amount of this dopant actually incorporates into the BiFeO3 phase. Copyright © 2017 John Wiley & Sons, Ltd.

Reaction between lithium indenyl and a chlorine substituted alpha diimine of the form [{Cl(NPh)2}C)]2 unexpectedly yielded the corresponding NH rearranged derivative [PhN(H)C(C9H6)]2 (1) rather than the predicted symmetrical α-diimine. This compound 1 was characterised by 1H NMR, 13C{1H} NMR and mass spectrometry, and additionally by X-ray diffraction. It was found that 1 was the first indene-substituted and symmetric secondary amine which was also highly fluorescent in DMSO. The reactivity of 1 towards simple inorganic and organometallic transition metals precursors based on the MX2 fragments, where M = Group 10 metals and X = halides or methyl groups, has been investigated. Surprisingly, the reaction with [PtMe2(COD)] led to the coupling reaction between the indenyl groups incorporated at the C-C ligand backbone and a new ligand (2) was discovered, in an attempt to synthesise the metal-linked diamine. Single crystal X-ray diffraction studies confirm this compound 2 to feature coupled indenyl residues and delocalised C-C bonds in the solid state. Structural authentication by X-ray crystallography showed compound 2 to be a very rare example of flat and extended aromatic organic molecule and mass spectrometry, IR and NMR spectroscopy were carried out to gain further insight into the solid state and solution phase structures. Further experiments to synthesise analogues of [PhN(H)C(Ind)]2 aiming to shift a likely equilibrium in favour the imine tautomer, by introducing bulky ortho substituents onto the benzene ring (R = Me, iPr) showed the presence of the imine tautomer to be increasingly favoured in 1H NMR spectra, with an increase in the steric bulk of the ortho substituents. However, the enamine tautomer is still observed to a minor extent even with isopropyl substituents and yields of these desired compounds were low on steric grounds.

The applications of coordination chemistry to molecular imaging has become a matter of intense research over the past 10 years. In particular, the applications of bis(thiosemicarbazonato) metal complexes in molecular imaging have mainly been focused on compounds with aliphatic backbones due to the in vivo imaging success of hypoxic tumors with PET (positron emission tomography) using 64CuATSM [copper (diacetyl-bis(N4-methylthiosemicarbazone))]. This compound entered clinical trials in the US and the UK during the first decade of the 21st century for imaging hypoxia in head and neck tumors. The replacement of the ligand backbone to aromatic groups, coupled with the exocyclic N's functionalization during the synthesis of bis(thiosemicarbazones) opens the possibility to use the corresponding metal complexes as multimodal imaging agents of use, both in vitro for optical detection, and in vivo when radiolabeled with several different metallic species. The greater kinetic stability of acenaphthenequinone bis(thiosemicarbazonato) metal complexes, with respect to that of the corresponding aliphatic ATSM complexes, allows the stabilization of a number of imaging probes, with special interest in “cold” and “hot” Cu(II) and Ga(III) derivatives for PET applications and 111In(III) derivatives for SPECT (single-photon emission computed tomography) applications, whilst Zn(II) derivatives display optical imaging properties in cells, with enhanced fluorescence emission and lifetime with respect to the free ligands. Preliminary studies have shown that gallium-based acenaphthenequinone bis(thiosemicarbazonato) complexes are also hypoxia selective in vitro, thus increasing the interest in them as new generation imaging agents for in vitro and in vivo applications.

A novel, bioinspired approach to water remediation is presented in which poly-peptide molecules with specific affinity for non-biological inorganic materials are used to immobilize metal oxide nanoparticles suspended in an aqueous batch. Based on the concept of molecular recognition, the proof of concept demonstrated here comprises a two-stage incubation methodology, whereby TiO2 nanoparticles in very low concentrations (0.04 mg/ml and below) can be effectively removed from a water suspension after being recognized and selectively bound to a properly engineered inorganic-binding peptide. Operating all the time under extraordinary soft conditions of temperature and pH (T = 37 °C, pH 7), the specific methodology involves first attaching the innocuous biomolecules to a substrate and then using the entire assembly to immobilize and remove the suspended nanoparticles. The whole procedure is systematically monitored by FESEM, microRaman and UV–vis analytical measurements and reveal that the immobilization mechanism fits widely in Langmuir’s isothermal adsorption model, with the biomolecule acting as a kind of molecular glue that ensures a stable adhesion with the noxious nanoparticles.

[EN] A fluorescent sensor for the detection of trithiocyanuric acid (TCA) and Hg was developed based on competitive interactions: non-covalent stacking between g-CN and TCA vs coordinative interaction between TCA and Hg. Electrostatic simulations were used to evaluate the interactions and help describe the detection mechanism. Moreover, normalized 2D fluorescence contour plots have been used to understand the fluorescence phenomenon. When TCA was added into a g-CN nanosheet solution free of Hg, TCA interacted with g-CN nanosheets via hydrogen bonding and π-π interactions, resulting in fluorescence quenching of the g-CN nanosheets. However, upon the addition of Hg, the fluorescence of the TCA-g-CN nanosheet hybrid system was restored, due to coordination of Hg with TCA through the S atoms, breaking the TCA-g-CN stacking interaction. Our results provide a new approach for the design of multifunctional nanosensors suitable for the detection of environmental pollutants., The present work is supported by the National Natural Science Foundation of China (No. 21607044), the Natural Science Foundation of Hebei Province (No. B2017502069) and the Fundamental Research Funds for the Central Universities (No. 2018MS113). All data sup-porting this study are provided as supplementary information accom-panying this paper. T.D.J. wishes to thank the Royal Society for a Wolfson Research Merit Award.

[EN] The conventional solid state processing of bulk Ti,Sm co-doped BiFeO ceramics typically produces a complex micro-nanostructure which exhibits an effective decrease of the leakage conductivity. This same nanostructured configuration however confines the mobility of the ferroelectric domains and in this way the potential piezoelectric response of the formulated composition remains restrained. Hereby, a two-step doping strategy based on a simple surface modification approach is proposed which eventually allows for suitably engineering the microstructural development of the material, leading to a coarsened configuration where the conductivity is kept in low levels while the piezoelectric response is satisfactorily released for practical purposes., [ES] El procesamiento convencional en estado sólido de materiales cerámicos en volumen deBiFeO3co-dopado con Ti y Sm, típicamente produce una compleja micro-nanoestructuraque permite una reducción efectiva de la conductividad eléctrica del material (corrientesde fuga). Sin embargo, esta misma configuración nano-estructurada también reduce lamovilidad de los dominios ferroeléctricos y por ello, la potencial respuesta piezoeléctricade la composición formulada permanece confinada. En este trabajo se propone el empleo de una estrategia de dopado en dos etapas, basada en una sencilla aproximación de modi-ficación superficial, con la cual es posible dise ̃nar y controlar adecuadamente el desarrollomicroestructural del sistema, dando lugar a un engrosamiento de la microestructura quepermite mantener la conductividad del material en bajos niveles al tiempo que libera sat-isfactoriamente su respuesta piezoeléctrica., This work was supported by the Spanish Ministry of Economyand Competitiveness (MINECO) through MAT2016-80182-Rand MAT2014-59210-JIN projects. Dr. T. Jardiel acknowledgesthe European Science Foundation (ESF) and the Ramon y Cajal Program of MINECO for the financial support. Dr. D.G.Calatayud also acknowledges the Fundación General CSIC(ComFuturo Program) for the financial support.

We have developed a green and robust fluorogenic (λex = 410 nm, λem = 510 nm) cellulose membrane using graphene oxide (GO) as a construct for simultaneous copper ion recognition and filtration at environmentally relevant levels. The detection limit and removal limit of Cu2+ are 7.3 × 10−7 M and 1000 ppm, respectively. The simplicity and scalability achieved for the detection and removal of metal ions in waste water is particularly noteworthy given the significant problems associated with metal ion pollution of drinking water., The present work was supported by the National Key Research and Development Program of China (Grant #: 2017YFC0210201 and 2016YFC0204102) and the National Natural Science Foundation of China (Grant #: 21607044, 51378204, and 51379077). This work was also supported by the Natural Science Foundation of Hebei Province (Grant #: B2017502069 and E2016502096) and the Fundamental Research Funds for the Central Universities (Grant #:2016MS108). T. D. J. wishes to thank the Royal Society for a Wolfson Research Merit Award. All data supporting this study are provided as supplementary information accompanying this paper (ESI†).

The encapsulation of CdSe nanocrystals within single‐walled carbon nanotube (SWNT) cavities of varying dimensions at elevated temperatures under strictly air‐tight conditions is described for the first time. The structures of CdSe nanocrystals under confinement inside SWNTs was established in a comprehensive study, combining both experimental and DFT theoretical investigations. The calculated binding energies show that all considered polymorphs [(3:3), (4:4), and (4:2)] may be obtained experimentally. The most thermodynamically stable structure (3:3) is directly compared to the experimentally observed CdSe structures inside carbon nanotubes. The gas‐phase DFT‐calculated energy difference between “free” 3:3 and 4:2 structures (whereby 3:3 models a novel tubular structure in which both Cd and Se form three coordination, as observed experimentally for HgTe inside SWNT, and 4:2 is a motif derived from the hexagonal CuI bulk structure in which both Cd and Se form 4 or 2 coordination) is surprisingly small, only 0.06 eV per formula unit. X‐ray powder diffraction, Raman spectroscopy, high‐resolution transmission electron microscopy, and energy‐dispersive X‐ray analyses led to the full characterization of the SWNTs filled with the CdSe nanocrystals, shedding light on the composition, structure, and electronic interactions of the new nanohybrid materials on an atomic level. A new emerging hybrid nanomaterial, simultaneously filled and beta‐d‐glucan coated, was obtained by using pristine nanotubes and bulk CdSe powder as starting materials. This displayed fluorescence in water dispersions and unexpected biocompatibility was found to be mediated by beta‐d‐glucan (a biopolymer extracted from barley) with respect to that of the individual inorganic material components. For the first time, such supramolecular nanostructures are investigated by life‐science techniques applied to functional nanomaterial characterization, opening the door for future nano‐biotechnological applications.

In the complex multicomponent formulation of standard commercial varistors used in high tension devices, those based in the ZnO–Bi 2 O 3 –Sb 2 O 3 (ZBS) ternary system, the presence of iron is ordinarily prevented in any of its plausible sources: dopant, impurity and/or unwanted contamination. Otherwise the material undergoes a systematic degradation in its electrical performance which rapidly disallows it for practical uses. In order to understand the origin of such degradation phenomena, we have deliberately doped the ZBS varistor composition with different amounts of Fe 2 O 3 . The research here presented evidences that the prime reason for the varistor electrical ruination is the progressive incorporation of iron inside the spinel secondary grains, which eventually leads to the formation of a highly conductive skeleton of secondary phases with an unbearable level of leakage currents below the varistor breakdown voltage.

Sol–gel synthesised TiO2 developed by our group was modified through the addition of nickel nitrate and ammonium carbonate in the synthesis process. Photocatalysts were synthesised with different Ni/Ti molar ratios (0.015, 0.030, 0.045) and constant Ni/N ratio equal to 1.5 and subjected to post-calcination at temperatures of between 400 °C and 700 °C. Characterisation was carried out with: X-ray diffraction (XRD), UV–vis diffusive reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDX), thermal analysis (TGA, DTA), aggregate size distribution, Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption-desorption isotherm (BET). Photoactivity in terms of photocatalytic hydrogen production was tested using a suspension of photocatalyst at 25 vol.% methanol. With a continuous flow of N2 in headspace the hydrogen produced was conducted to a gas chromatograph for quantification. No evidence of the presence of N was found in the photocatalyst. However, the presence of Ni enhanced TiO2 photoactivity, with a calcination temperature of 550 °C resulting in the highest photoactivity value of 260.76 μmol h−1.

A versatile synthesis method is proposed to fabricate hierarchical anatase microspheres under soft conditions and rendering batch volumes significantly large for practical scale-up preparation. The strategy is based on the use of non-aqueous conditions to prevent the accelerated hydrolysis of the Titanium precursor. Water traces from the air atmosphere are only incorporated during the vaporization stage, allowing a controlled precipitation process. Diluted precursor solutions and ethanolic medium promote the self-organization of the precipitated nanoparticles into stable units of spherical shape. The calcination of the obtained powder finally leads to a homogenous, monodisperse and easy to handle population of nanostructured anatase microspheres with high crystallinity and large surface area.

Functional porphyrins have attracted intense attention due to their remarkably high extinction coefficients in the visible region and potential for optical and energy‐related applications. Two new routes to functionalised SWNTs have been established using a bulky ZnII‐porphyrin featuring thiolate groups at the periphery. We probed the optical properties of this zinc(II)‐substituted, bulky aryl porphyrin and those of the corresponding new nano‐composites with single walled carbon nanotube (SWNTs) and coronene, as a model for graphene. We report hereby on: i) the supramolecular interactions between the pristine SWNTs and ZnII‐porphyrin by virtue of π–π stacking, and ii) a novel covalent binding strategy based on the Bingel reaction. The functional porphyrins used acted as dispersing agent for the SWNTs and the resulting nanohybrids showed improved dispersibility in common organic solvents. The synthesized hybrid materials were probed by various characterisation techniques, leading to the prediction that supramolecular polymerisation and host–guest functionalities control the fluorescence emission intensity and fluorescence lifetime properties. For the first time, XPS studies highlighted the differences in covalent versus non‐covalent attachments of functional metalloporphyrins to SWNTs. Gas‐phase DFT calculations indicated that the ZnII‐porphyrin interacts non‐covalently with SWNTs to form a donor–acceptor complex. The covalent attachment of the porphyrin chromophore to the surface of SWNTs affects the absorption and emission properties of the hybrid system to a greater extent than in the case of the supramolecular functionalisation of the SWNTs. This represents a synthetic challenge as well as an opportunity in the design of functional nanohybrids for future sensing and optoelectronic applications.

The energetic losses associated with the leakage currents can represent a serious problem for the efficient performance of ZnO-based varistor ceramics. However, by properly tailoring the microstructure of these ceramics, the leakage currents can be drastically reduced. Pursuing this goal, two intended doping strategies have been attempted over a standard high-voltage varistor formulation based on the ZnO–Bi2O3–Sb2O3 ternary system. The first strategy focuses on the stabilization of the secondary Zn2.33Sb0.67O4 spinel particles; on cooling the ceramic, this spinel phase reversely transforms into a pyrochlore conductive structure whose presence favors the current flow in the varistor prebreakdown region (i.e., high leakage current values). A certain amount of TiO2 incorporated into the spinel lattice impedes its reverse transformation to pyrochlore, thus reducing the varistor leakage current. The second strategy leans on the insertion of an insulating phase in between the skeleton of Bismuth-rich phases. This skeleton provides a continuous network through the whole varistor microstructure for the current to flow, so the inclusion of an insulating phase may serve as a physical blockade to break off that connectivity. Such a phase is yielded by properly doping with SiO2. Eventually, the combination of both strategies leads to a decrease of two orders of magnitude in the varistor leakage current.

La produccion de hidrogeno a partir de agua mediante el empleo de semiconductores ceramicos con propiedades fotocataliticas ha adquirido especial relevancia en los ultimos anos, debido a su potencial uso para la obtencion de hidrogeno de un modo directo y limpio. En la busqueda de nuevos materiales que presenten propiedades fotocataliticas en la region visible del espectro solar, el dopado con metales de transicion ha demostrado ser un metodo eficaz de adecuar los valores de band gap del semiconductor. En este trabajo se aborda el estudio del efecto de la adicion de distintos dopantes (Fe, Ni, Cr, Mn, Co, Cu) sobre la estructura y valor de band gap del Bi4Ti3O12, con el objetivo de mejorar su actividad fotocatalitica y hacerlo activo en el visible. En este sentido se han preparado materiales dopados basados en BIT por procesamiento en estado solido, obteniendose distintas proporciones de una fase adicional con estructura tipo silenita, Bi12TiO20. Como consecuencia del dopado se produce un desplazamiento de los espectros de absorcion a mayores longitudes de onda, y por tanto a menores valores del band gap. Los valores obtenidos de los band gaps son bastante prometedores para muchas de las composiciones, promoviendo el estudio de sus propiedades fotocataliticas.

The surface modification of graphene oxide (GO) is carried out via the supramolecular functionalization route using a Zn(II)-porphyrin which is soluble in common organic solvents on basis of long alkyl chains present at the exocyclic positions. This acts as a dispersing agent and decorates the surface of the graphene oxide uniformly, giving rise to a new nanohybrid denoted Zn(II)-porphyrin@GO. The resulting Zn(II)-porphyrin@GO nanohybrid forms a stable dispersion in ethanol (as characterized by several different spectroscopic techniques such as UVvis, Fourier transform infrared, Raman). The morphology of Zn(II)-porphyrin@GO nanohybrid is investigated by atomic force microscopy (AFM) and transmission electron microscope (TEM)/selected area electron diffraction. Both TEM and AFM measurements indicate that the Zn(II)-porphyrin self-assemble onto the surface of graphene oxide sheets. Steady-state and time-resolved fluorescence emission studies in the dispersed phase, and as a thin film, point toward the strongly quenched fluorescence emission and lifetime decay, suggesting that energy transfer occurs from the singlet excited state of Zn(II)-porphyrin unit to GO sheets., rof. Jeremy K. M. Sanders, FRS and the Sanders Group at Cambridge, as well as Prof. Sijbren Otto is acknowledged for training, helpful discussions in supramolecular chemistry and porphyrin synthesis and mentorship to SIP group. Dr. Amy Kieran, Dr. Lok Tong, and Dr. Rory Arrowsmith are thanked for involvement with initial stages of the porphyrin synthesis and characterization. S.I.P. and S.W.B. thank The Royal Society and STFC for funding. B.Y.M. thanks the University of Bath for a studentship (ORS). B.J.H. thanks the University of Bath for a DTC studentship. The SIP group thanks to the EPSRC for funding, as a member of the Centre of Graphene Science. The authors also acknowledge the ERC for the Consolidator Grant O2SENSE.

The area of biomedical imaging is fast becoming an active focus for the utilization of graphene within a variety of imaging modalities. Graphene can be oxidized to produce a material with a high degree of functionality and has led to its expansion as a platform for the immobilization of fluorescent and radiolabeled molecules. Its large surface area has allowed graphene and its oxides to be modified with a variety of molecules that enhance biocompatibility, selectivity, and therapeutic potential. This chapter highlights recent developments in the use of targeted fluorogenic or radiolabeled graphene materials that can be used to image cancers via fluorescence, positron emission tomography, and single-photon emission computed tomography modalities. Key emphasis is placed on the nanocomposites that are designed to provide additional therapeutic effects. The capacity of these composites to be internalized by cells and tumors is discussed to appreciate the future perspective of graphene and its congeners as therapeutic multimodal imaging agents.

An effective synthesis strategy for the extensive fluorination of the TiO2 anatase lattice has been developed which provides a highly stable blue-colored titania powder. The process also produces a convenient faceted morphology of the doped nanoparticles. Both theoretical and experimental data indicate an ordered atomic structure, in which an exceptionally high amount of fluorine ions substitute oxygen ions in the TiO2 lattice. The extra-electrons borne by fluorine are stabilized by lattice Ti cations via a mechanism of valence induction, eventually leading to a consequent high amount of reduced Ti3+ centers. Such structure, whose general formula can be expressed as Ti4+(1-x)Ti3+xO2–(2-x)F–x, confers an excellent stability to the as-synthesized nanoparticles (in spite of the excess electrons), explaining for example why the blue color is retained even upon storage in ambient atmosphere. But moreover, the high concentration of the relatively shallow Ti3+ generated states also form a sort of sub-band close to the bottom of the conduction band itself. The whole effect results in a tangible decrease (0.2 eV) of the anatase band gap which allows an inspiring upgrading of its UV photocatalytic activity. Our results also suggest that narrowing the band gap is insufficient for a substantial improvement in the visible light harvesting., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the projects IPT-2011-1113-310000 (NANOBAC), MAT2013-40722-R (SCOBA), MAT2013-47878-C2-1-R and CTQ2012-30751 and by the Comunidad de Madrid through the project MULTIMAT-CHALLENGE P2013/MIT-2862. T.J. also acknowledges the European Science Foundation (ESF).

Fluorine species adsorbed on the surface of TiO2 anatase nanoparticles improve their photocatalytic performance by reducing the recombination rate of photogenerated electrons and holes. Trifluoroacetic acid (TFAA) has been recently proposed as a promising harmless substitute for hydrofluoric acid (HF) in preparing fluorine-modified anatase with good scavenger properties. However the photocatalytic performance of the TiO 2 nanoparticles also depends on their specific morphology, by which the number and type of crystal facets, which remain exposed, are determined. A comprehensive study is presented in this contribution which for the first time describes the role of TFAA in stabilizing the highly photoactive {001} TiO 2 facets. Furthermore, by reducing the amount of water incorporated into the reaction medium, a simple one-step synthesis method is also proposed that allows the preparation of TFAA-modified anatase nanoparticles with specific morphology and selected stabilized facets, eventually yielding a semiconductor material with excellent photocatalytic properties. © 2013 The Royal Society of Chemistry., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the projects IPT-120000-2010-033 (GESHTOS), IPT-2011-1113-310000 (NANOBAC), CICYTMAT 2010-16614, MAT2010-18432 and CSD2008-00023. Dr T. Jardiel also acknowledges the JAE-Doc contract of the Spanish National Research Council (CSIC) and the European Science Foundation (ESF). Dr M. Peiteado acknowledges the Ramon y Cajal Program of MINECO for the financial support.

TiO2 nanoparticles with tailored morphology have been synthesized under exceptionally soft conditions. The strategy is based on the use of a non-aqueous alcoholic reaction medium in which water traces, coming either from the air (atmospheric water) or from an ethanol–water azeotropic mixture (ethanol 96%), are incorporated in order to accelerate hydrolysis of the Ti–precursor. Moreover, organic surfactants have been used as capping agents so as to tailor crystal growth in certain preferential directions. Combinations of oleic acid and oleylamine, which lead to the formation of another surfactant, dioleamide, are employed instead of fluorine-based compounds, thus increasing the sustainability of the process. As a result, TiO2 nanostructured hierarchical microspheres and individual nanoparticles with exposed high-energy facets can be obtained at atmospheric pressure and temperatures as low as 78 °C.

The fabrication of hierarchical anatase microspheres with potential photocatalytic properties eventually comprises a consolidation step in which a high degree of crystalline order is typically achieved through conventional electric heating treatments. This however entails a substantial reduction in the specific surface area and porosity of the powders, with the consequent deterioration in their photocatalytic response. Here, we have tested the employ of microwave heating as an alternative energy-saving sintering method to promote fast crystallization. The results obtained suggest that under the microwave radiation, the TiO2 hierarchical structures can effectively crystallize in a drastically reduced heating time, allowing the specific surface area and the porosity to be kept in the high values required for an improved photocatalytic performance., This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) through the projects IPT-120000-2010-033 (GESHTOS), IPT-2011-1113-310000 (NANOBAC), CICYTMAT 2010-16614, MAT2010-18432 and CSD2008-00023. Dr T. Jardiel also acknowledges the JAE-Doc contract of the Spanish National Research Council (CSIC) and the European Science Foundation (ESF). Dr M. Peiteado acknowledges the Ramon y Cajal Program of MINECO for the financial support.