Electroconductive biomaterials have been emerged to support the recovery of the degenerated electrically conductive tissues, especially the cardiac ones after myocardial infarction. This work describes the development of electroconductive scaffolds for cardiac tissue regeneration by using a biocompatible and conductive polymer - i.e. poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) - combined with a biomimetic polymer network of gelatin. Our approach involves the use of dehydrothermal (DHT) treatment in vacuum conditions to fabricate suitably stable scaffolds without using any additional crosslinking agent. The resulting scaffolds mimic the Young modulus - an essential mechanical performance - of native cardiac tissue and are endowed with a well-interconnected porosity coupled with a good swelling ability and stability in physiological conditions. Additionally, the presence of PEDOT:PSS is able to enhance the electroconductivity of resulting materials. All the scaffolds are non-cytotoxic towards H9C2 cardiomyoblasts and the presence of PEDOT:PSS enhances cell adhesion - especially at early timeframes, an essential condition for a successful outcome after the implantation - proliferation, and spreading on scaffolds. Considering the permissive interaction of scaffolds with cardiomyoblasts, the present biomimetic and electroconductive scaffolds display potential applications as implantable biomaterials for regeneration of electroconductive tissues, especially cardiac tissue, and as a promising 3D tissue model for in vitro biomolecules screening.

Photo-electrochemical reduction of carbon dioxide can be currently considered as the most efficient approach for CO2 transformation into clean and storable fuels and chemicals. In a Photo-Electrochemical Cell (PEC) rapid spatial separation of the photo-generated carriers and their transport kinetics within the photo-electrodes materials are fundamental to achieve high-performance devices avoiding charges recombination. In 2010[1] Wang showed how the piezoelectric dipole arising from external stimuli in non-centrosymmetric crystals can efficiently modify the charge transfer properties both in the bulk phase and at the surface of semiconductors[2]. In this regard, photoactive materials simultaneously displaying semiconducting behavior and ferroelectric properties (i.e. ferroelectric-enhanced piezo-phototronic materials) represent a promising option as PEC photo-electrodes, allowing the modification of cells efficiency by electrically polarizing the materials. Whit this in mind Aurivillius compounds seem to be the perfect candidates. This peculiar class of perovskites, thanks to their unique layered structure, generally allows the migration of photo-generated holes and electrons within different areas of the materials, facilitating charge separation and incrementing cells efficiency. In addition, they are endowed with strong spontaneous ferroelectric polarization which can be used to exploit the piezo-phototronic effect. In this work the utilization of different Aurivillius compounds (i.e. Bi4Ti3O12 - BiTO - and Bi2MoO6 - BiMO) as photo-electrode materials for solar conversion has been studied in details. The use of BiTO and BiMO for the photocatalytic reduction of CO2 has recently been reported, however the main strategies to develop optimized ferroelectric-enhanced photo-electrodes of these materials and their utilization for the ferroelectric potential-assisted CO2 reduction has never been fully investigated. In this work, BiTO and BiMO photo-electrodes were fabricated and accurately optimized to obtain both hierarchically oriented nanostructures and thin-film layers via in situ hydrothermal deposition and through a sol-gel/spin coating coupled process respectively. These architectures were therefore compared to evaluate the effect of ferroelectric potential on the photo-electrochemical performances of the optimized photo-electrodes. Current density increments of about 50% under the optimal ferroelectric polarization were obtained for the spin-coated samples and enhanced charge transfer abilities were also registered demonstrating the possibility to adopt ferroelectric polarization coupled with an external bias to effectively control the migration of photo-generated charges in the CO2 photo-electrochemical reduction. ______________ References: [1]Whang, Z. L.; Nano Today 2010, 5, 540-552. [2]Pan, L.; Sun, S.; Chen, Y.; Wang, P.; Wang, J.; Zhang, X.; Zou, J.-J.; Whang, Z. L.; Adv. Energy Mater. 2020, 10, 2000214.

In recent years, bismuth-based photocatalysts have been receiving increasing attention in photocatalysis, due to their appropriate bandgap and tunable surface structure, which make them suitable also for the photocatalytic reduction of CO21. Their performances, however, are still limited by the fast charge carriers recombination. Recently, the exploitation of piezo/ferro-electric potentials in photo-active semiconductors has been adopted as an effective strategy to modulate the charge transfer properties both in the bulk phase and at the surface of semiconductors (i.e. piezo-phototronic effect)2. In this perspective Bismuth-based Aurivillius compounds, owing to their usually strong spontaneous ferroelectric polarization represent a promising option as cell photo-electrodes, allowing the increase of cell efficiency by electrically polarizing the materials. In addition, thanks to their unique layered structure, this peculiar class of perovskites allows the migration of photo-generated holes and electrons within different areas of the materials, thus intrinsically facilitating charge separation. In this work, the utilization of different Aurivillius compounds (i.e. Bi4Ti3O12 - BiTO, and Bi2MoO6 - BiMO) as photo-electrode materials for solar conversion has been studied in detail. The use of BiTO and BiMO for the photocatalytic reduction of CO2 has recently been reported, however, the main strategies to develop optimized ferroelectric-enhanced photo-electrodes of these materials and their utilization for the ferroelectric potential-assisted CO2 reduction has never been fully investigated. BiTO and BiMO photo-electrodes were fabricated and accurately optimized to obtain both hierarchically oriented nanostructures with different morphologies (i.e. nanosheet/nanorod arrays), and thin-film layers via in situ hydrothermal deposition and through a sol-gel/spin coating coupled process respectively. The effect of the ferroelectric potential on the photo-electrochemical performances of the optimized photo-electrodes with different architectures was therefore accurately studied. Density current increments and enhanced charge transfer ability were registered under the optimal ferroelectric polarization which was directly reflected in the CO2 photo-electrochemical reduction performances. This work, therefore, demonstrates the possibility to adopt ferroelectric polarization coupled with an external bias to effectively control the migration of photo-generated charges in bismuth-based Aurivillius semiconductors for the CO2 photo-electrochemical reduction. References [1]Liu, X., Xiao, J., Ma, S., Shi, C., Pan, L., Zou, J.-J.; ChemNanoMat 2021, 7, 684-698. [2]Pan, L.; Sun, S.; Chen, Y.; Wang, P.; Wang, J.; Zhang, X.; Zou, J.-J.; Whang, Z. L.; Adv. Energy Mater. 2020, 10, 2000214.

This work describes the development of electroconductive hydrogels as injectable matrices for neural tissue regeneration by exploiting a biocompatible conductive polymer - poly(3,4-ethylenedioxythiophene)- poly(styrenesulfonate) (PEDOT:PSS) - combined with a biomimetic polymer network made of gelatin. Our approach involved also genipin - a natural cross-linking agent - to promote gelation of gelatin networks embedding PEDOT:PSS. The achieved results suggest that physical-chemical properties of the resulting hydrogels, like impedance, gelation time, mechanical properties, swelling and degradation in physiological conditions, can be finely tuned by the amount of PEDOT:PSS and genipin used in the formulation. Furthermore, the presence of PEDOT:PSS (i) enhances the electrical conductivity, (ii) improves the shear modulus of the resulting hydrogels though (iii) partially impairing their resistance to shear deformation, (iv) reduces gelation time and (v) reduces their swelling ability in physiological medium. Additionally, the resulting electroconductive hydrogels demonstrate enhanced adhesion and growth of primary rat cortical astrocytes. Given the permissive interaction of hydrogels with primary astrocytes, the presented biomimetic, electroconductive and injectable hydrogels display potential applications as minimally invasive systems for neurological therapies and damaged brain tissue repair.

Cosa avranno mai in comune la riparazione ossea con l'energia solare o le esplorazioni spaziali? Sono tutti traguardi tecnologici che hanno preso ispirazione da fenomeni naturali: la biomimetica ci guida al progresso e, in tutto ciò, la ceramica, nelle sue infinite declinazioni, è il comune denominatore. Se parliamo di medicina rigenerativa, il componente ceramico principe è l'idrossiapatite. E' il basilare costituente delle nostre ossa che può essere utilizzato per creare dispositivi che stimolano le cellule alla ricostruzione dei tessuti o addirittura per realizzare "capsule intelligenti" che racchiudono farmaci da consegnare solo dove necessario, limitando gli effetti collaterali agli organi circostanti. Inoltre, i materiali ceramici si trovano in sempre più componenti che caratterizzano la nostra vita di tutti i giorni e, negli ultimi anni, hanno trovato ampio spazio in tecnologie e procedure innovative per ottenere energia elettrica da fonti rinnovabili come il sole. La fotosintesi clorofilliana è il più importante processo naturale che immagazzina energia solare e produce ossigeno facendo crescere le piante. Lo stesso meccanismo di trasformazione, semplice e sostenibile, può essere replicato artificialmente con materiali sintetici che sfruttano l'energia del sole per produrre energia alternativa rispetto ai combustibili fossili. Passando ad un settore più di nicchia, la ceramica è uno dei pochi materiali in grado di sopravvivere agli ambienti estremi tipici dell'aerospazio. In che modo i ceramici vadano ingegnerizzati ed assemblati insieme ad altri componenti ci viene insegnato dalla struttura di rettili, uccelli e insetti che, dopo processi evolutivi, hanno affinato sistemi organizzati in strutture gerarchiche che permettono loro di resistere a fortissimi impatti meccanici ed importanti sbalzi di temperatura.

In this work, dye-sensitized solar cells containing seawater-based electrolytes were realized and investigated. The influence of the seawater composition on the electrochemical properties of the iodide/triiodide redox mediator was determined. High triiodide diffusion coefficient and ionic conductivity were assessed for seawater electrolytes through cyclic and linear voltammetry and impedance spectroscopy. Moreover, a notable influence of the seawater electrolyte on the charge transfer mechanism at the photoanode/dye/electrolyte interfaces was observed and deeply discussed. The ions, naturally present into seawater, reduce the charge recombination mechanism at the photoanode/electrolyte interface and promote a downward shift of the TiO conduction band, thus increasing the final DSSC efficiencies of 23% if compared with traditional devices containing water. The best seawater-based solar cell provides a photo-electrical conversion efficiency equal to 0.37% with 1.09 mA cm as short circuit current density. To the best of our knowledge, this is the first time that seawater is used as a key component for an energy production technology and the obtained results show the great potentiality of this green and recyclable element.

In this work, copper oxides-based photocathodes for photoelectrochemical cells (PEC) were produced for the first time by screen printing. A total 7 x 10(-3) g/m(2) glycerine trioleate was found as optimum deflocculant amount to assure stable and homogeneous inks, based on CuO nano-powder. The inks were formulated considering different binder amounts and deposited producing films with homogenous thickness, microstructure, and roughness. The as-produced films were thermally treated to obtain Cu2O- and Cu2O/CuO-based electrodes. The increased porosity obtained by adding higher amounts of binder in the ink positively affected the electron transfer from the surface of the electrode to the electrolyte, thus increasing the corresponding photocurrent values. Moreover, the Cu2O/CuO system showed a higher charge carrier and photocurrent density than the Cu2O-based one. The mixed Cu2O/CuO films allowed the most significant hydrogen production, especially in slightly acid reaction conditions.

Layered Double Hydroxides (LDH) are versatile materials that can be applied to different fields. Recently their employment in Dye-Sensitized Solar Cells (DSSCs) technology has been reported. The heart of this technology is the photoanode, a semiconductor layer sensitized with dye molecules able to absorb the sunlight. However, the traditional dye molecules are quite expensive and sensitive to thermal degradation and the sensitization process requires time and costs. The possibility to directly intercalate the dye in the LDH interlayer makes these materials very promising as innovative photoanodes. This aspect in fact would help to reduce both the time and the costs, overcome charge-transfer and recombination phenomena issues and finally increase the Photo-Conversion Efficiency (PCE) and stability. In this work, an Eosin Y-intercalated ZnAl LDH was prepared by coprecipitation and applied as photoanode material. For this purpose, a screen-printing ink was formulated and then applied onto a conductive transparent substrate. Then, complete DSSC prototypes were assembled and tested. A comparison with an analogous LDH intercalated with terephthalate and sensitized with Eosin Y showed a beneficial effect due to the presence of the dye intercalated in the structure rather than adsorbed on the surface, increasing the stability (tested for 1500 h) and efficiency of the related DSSCs. A 0.11 mA cm-2 of JSC, 568 mV of VOC and a PCE of 0.019% were obtained for the Eosin Y intercalated LDH based photoanode. Moreover, the interaction between the intercalated dye and the LDH sheets allowed to reduce charge recombination phenomena and thus to increase VOC and PCE values.

In light of the ever-growing demand of modern electronics for wearable integrated optoelectronic devices, Fiber-shaped Dye-Sensitized Solar Cells (FDSSCs) have gained increasing interest over the last years as suitable energy production systems for the development of the next generation of smart products. To fulfill the wearable concept, it is important to design long and flexible thin-film FDSSCs capable of adapting to curved surfaces such as the human body. In this study, for the first time, several key parameters towards the optimization of long and flexible FDSSCs based on inexpensive TiO2 as photoanode material and a fully organic thiazolo [5,4-d]thiazole-based sensitizer (TTZ5) were studied. First, the influence of photoanode thickness on photovoltaic performance was evaluated in 3.5 cm-long devices, for which an optimal thickness of 10 ?m was identified, obtaining a maximum PCE of 1.57 ± 0.15%. Long (10 cm) complete FDSSCs were then fabricated, using thin layer photoanodes of about 5 ?m which were instead found to be the optimal choice for such devices. The as-obtained FDSSCs based on TTZ5 possess dimensions appealing for future applications while also delivering a remarkable PCE of 1.23 ± 0.04%, thus paving the way for further optimization of thin-film flexible long FDSSCs based on organic sensitizers.

The development of new materials based on abundant elements, reduced toxicity is today crucial for the next generation of energy device. Titanium-doped hydroxyapatite (TiHA) was tested for the first time as photoanode material for Dye - Sensitized Solar Cells (DSSCs). The chemical composition and energy structure of TiHA powders with increasing titanium content (5 wt.%, 10 wt.% and 15 wt.%) were extensively characterized by surface electron spectroscopies, XPS and UPS. Their compatibility with conventional ruthenium-based dyes molecules was also assessed, producing considerable uptake. TiHA films were produced by screen-printing technique and XRD analyses confirm the presence of apatitic structure. The film properties were completely determined by optical, morphological (FE-SEM) and functional characterizations. Finally, TiHA-based DSSCs were assembled and their photovoltaic performance were assessed. The best efficiency, equal to 0.14 %, was obtained for the TiHA containing 15 wt.% of titanium. These results open the path for the possible application of doped hydroxyapatite as novel materials for energy conversion systems.

A set of three new Ru(II) polypyridyl complexes decorated with 5-aryl tetrazolato ligands (R-CN4)(-), (D series, namely D1, D3 and D4), is presented herein. Whereas complex D1 represents the pyrazinyl tetrazolato analogue of a previously reported Ru(II) complex (D2) with the general formula cis-[(dcbpy)(2)Ru(N<^>N)](+), in which dcbpy is 2,2'-bipyridine-4,4'-dicarboxylic acid and N<^>N is the chelating 2-pyridyl tetrazolato anion, the design of the unprecedented Ru(II) species D3 and D4 relied upon a completely different architecture. More specifically, the molecular structure of thiocyanate-based species cis-[(dcbpy)(2)Ru(NCS)(2)], that is typically found in benchmark Ru(II) dyes for dye sensitized solar cell (DSSCs), was modified with the replacement of two of the -NCS ligands in favour of the introduction of 5-aryl tetrazolato anions, such as the deprotonated form of 5-(4-bromophenyl)-1H-tetrazole, for complex D3 and 5-(4-cyanophenyl)-1H-tetrazole in the case of complex D4. To streamline the behavior of the D series of Ru(II) complexes as photosensitizers for DSSCs, an in-depth analysis of the excited state properties of D1, D3 and D4 was performed through TDDFT calculations and TDAS (nanosecond transient difference absorption spectroscopy). The obtained results highlight a trend that was confirmed once D1, D3 and D4 were tested as photosensitizers for DSSC under different conditions. Along the series of the Ru(II) complexes, the neutrally charged species D3 and D4 displayed the best photovoltaic performances.

Due to the superior optical and electronic properties, all-inorganic perovskite materials have been widely used in optoelectronic device and energy conversion systems such as solar cells. However, photoelectrochemical devices with all-inorganic perovskite as photo-active material used in aqueous solution have been received not many attentions. In this work, the use of CsPbBr in photoelectrochemical system in direct contact with water is studied for the first time, considering also the post-mortem properties. Sub-micronic crystals of CsPbBr were synthetized by a conventional low temperature synthesis and the obtained materials were used to produce a photo-electrode for photo-electrochemical cell (PEC). The material was characterized and then tested to assess its electrochemical and photocatalysis properties. The particles showed high photocatalytic activity (more than 50% of Rhodamine degradation after 80 min) and promising photocurrent values of 11.7 µA cm and 2.25 ?A cm in reduction and oxidation conditions respectively. The synthesis conditions assured CsPbBr good stability in water up to 60 min. After this time, system passes from pure CsPbBr to a mixture of CsPbBr and CsPbBr still retaining part of its photoelectrochemical activity. The results showed that CsPbBr has good potentiality as photo-electrode material in water-based photoelectrochemical cell for the conversion of CO into fuels or chemicals.

Fiber-shaped Dye-Sensitized Solar Cells (DSSFs) represent one of the most interesting technologies aimed at the light harvesting and the production of electricity for wearable applications. In order to boost DSSFs commercialization, their production costs and environmental impact must be reduced. To this end, a suitable strategy could be to build thin film-based devices endowed with metal-free organic sensitizers, exploiting their higher molar extinction coefficients compared to typical ruthenium-containing organometallic dyes. In this work, three thiazolo[5,4-d]thiazole-based organic dyes, TTZ3, TTZ5 and TTZ7, capable of strongly absorb visible light, were used for the first time to manufacture titanium wire-based DSSFs. DSSFs based on a thin TiO2 layer (5 ?m) sensitized with the three organic dyes were prepared and tested and the obtained results show that power conversion efficiencies for the organic dyes (0.80%) are higher than that obtained with the reference N719 dye (0.45%). An efficiency of 0.99% with short circuit current density equal to 3 mA/cm2 was achieved when the TTZ7-based DSSFs were tested in diffuse illumination condition, highlighting the supremacy of these dyes compared to the metal-organic reference. The excellent photovoltaic performances of TTZ dyes were attributed to their better light harvesting properties, resulting in the production of higher photocurrent densities, which was confirmed by the electrochemical impedance spectroscopy (EIS) analysis. The superiority of organic dyes on DSSFs performances compared to N719, shown for the first time in this work, support the real possibility to apply these molecules for the preparation of efficient light-harvesting devices based on thin film photoanodes.

In this work new energy storage components were prepared depositing films made of polyaniline (PANI) modified with gold/magnetite nanoparticles on flexible graphite foils. Three types of composite materials termed PANI/FeO, PANI/Au/FeO and PANI/Au/FeO@Yne (where @Yne is a propynylcarbamate group) were obtained by electrosynthesis. Galvanostatic charge-discharge (CD) and impedance tests (EIS) were performed to verify their efficiency in charge storage properties: for the gold-containing electrodes PANI/Au/FeO and PANI/Au/FeO@Yne areal capacities values of 45.6 and 46.5 mAh cm were found in 0.5 M HSO + 0.1 M LiClO electrolyte solution at a current density of 0.5 mA cm. These values are twofold higher than those found for PANI/FeO electrodes and fourfold greater than those for PANI alone (11.0 mAh cm). In turn PANI/Au/FeO and PANI/Au/FeO@Yne were employed to assemble gel-state symmetric devices. CD, EIS and longtime resistance tests were made on the new devices that displayed an areal capacities of 100.0 mAh cm for PANI/Au/FeO and 73.6 mAh cm PANI/Au/FeO@Yne respectively. To our knowledge this is the first time that AuNP-modified magnetite nanoparticles are used in energy storage devices preparation.

Nowadays, reducing carbon dioxide emission in the atmosphere is one of the most important environmental issues that must be overcome. At the same time, low-cost and environmentally friendly technologies are necessary to produce renewable fuels able to replace the conventional fossil ones. Electrochemical cells (driven by solar energy) and photo-electrochemical cells (PECs) are among the main efficient technologies to get these challenging goals. Taking into account the PEC working mechanism, two different electrodes, based on photo-electrocatalytic and electrocatalytic materials able to drive reactions both under illumination or in dark conditions, are involved. In this review, recent results on carbon-based materials for electrocatalytic and photo-electrocatalytic carbon dioxide reduction are discussed. The properties and synthesis conditions applied to the preparation of conducting polymer and graphitic carbon nitride (g-C3N4) are described and discussed for their application in the photoactive electrodes. As for the electrodes to be applied in the electrocatalytic CO2 activation and conversion, light heteroelement-doped carbon nanomaterials have been taken into account as highly valuable metal-free candidate to run the process efficiently and selectively. For the latter process, also the influence of the electrolyte and the selectivity towards different reaction products will be discussed. All these data taken together indicate that a lot of work still has to be done to achieve high efficiency with metal-free organic-based electro- and photo-electrocatalysts applied to the carbon dioxide conversion. Anyhow, many seminal outcomes collected in the literature up to now clearly indicate the real possibility to replace highly costly metal-based materials with simply organic ones. © 2019, Accademia Nazionale dei Lincei.

The chemical complexity of traditional Dye Sensitized Solar Cells (DSSCs) electrolyte requires the development of high selectivity and catalytic counter-electrode (CE) materials for the triiodide target molecule. In this work is reported for the first time that molecularly imprinted polypyrrole (MIP-PPy) can help to overcome these challenges. Different template molecules such as 2-aminoacetic acid (Glycine) and L-2-aminopropionic acid (L-Alanine) are considered during the electropolymerization process in order to verify the application of MIP-PPy as CE. The use of low concentration of Glycine leads to a MIP-PPy film exhibiting higher catalytic activity and electrochemical properties on triiodide reduction than the non-imprinted polypyrrole (NIP-PPy) one. Gel-state DSSCs based on MIP materials were prepared and tested and the optimized MIP-PPy CE with Glycine as template showed an increase of around 20% of the power conversion efficiency and a reduction of 50% of the charge transfer resistance in comparison with the cells based on NIP-PPy. These results demonstrate the possibility to enhance the catalytic properties of PPy CE without adding any other materials or considerable modifications of the production process but simply increasing the electrode selectivity. (C) 2019 Elsevier Ltd. All rights reserved.

The formulation, development and optimization of water-based inks of platelet-like nanoparticles are the main objective of this work. As-synthesized Ni(OH)2 nanoparticles were dispersed and stabilized in aqueous suspension by PEI addition. The combination of DEG (cosolvent) with H2O shows the ideal values of surface tension and viscosity for piezoelectric inkjet printing, which exhibits a homogeneous jetting flow of the nanoplatelets suspension. The printed nanostructure was sintered at low temperature (325 °C) and the electrochemical overview of NiO electrode behavior was described. These printable pseudocapacitors tested by a three-electrode cell have showed a competitive specific capacitance, leading 92% and 78% of capacitance retention for 2000 cycles at scan rates of 1 and 2 A/g respectively, and a coulombic efficiency of 100%. The initial erformance of this printed NiO pseudocapacitor can be compared with others prepared by conventional methods. This new finding is expected to be particularly useful for the designing of micro-pseudocapacitors.

In this work the effect of different doping anions on transparency, photovoltaic efficiency and interface properties of electropolymerized polypyrrole (PPy) films as counter electrode in bifacial DSSCs was study. The transparency of the counter electrode becomes relevant in order to enhance the final device efficiency and for alternative application area like of Building-Integrated Photovoltaic. PPy was prepared by electrochemical process with doping anions: chloride, perchlorate, sulfate and dodecylbenzenesulfonate. PPy doped with high concentration (0.5 M) of small anions (chloride) produced the highest transparency film (65% at 525 nm), the DSSCs with highest efficiency ratio (close to 70%) and lowest device reflectance (11%). Considering all of these results, not only the transparency of counter electrode was found to influence the efficiency of the bifacial DSSCs, but also the optical properties of PPy/electrolyte interface. This interface is probably strictly affected to the PPy morphology produced by different doping anions and the electropolymerization process used. (C) 2017 Elsevier Ltd. All rights reserved.

This paper describes the electrosynthesis and characterization in alkaline solutions of two layered double hydroxides (LDHs) containing Co as divalent cation and Al or Fe as trivalent one on Pt supports. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) experiments demonstrated a capacitive behaviour. LDHs containing Al3+ or Fe3+ displayed different responses, highlighting a key role of the trivalent metal. High specific capacitances calculated from charge-discharge experiments at a current density of 1 A g(-1), were displayed by the two materials and resulted 854 and 869 F g(-1) for the Al or Fe containing LDH, respectively. The long-term cycling capability was also investigated giving satisfactory results.

Single carbon fibres were 360 degrees coated with zinc oxide (ZnO) thin films by pulsed laser deposition using a Q-switched CO2 laser with a pulse duration tau approximate to 300 ns, a wavelength lambda = 10.59 mu m, a repetition frequency f(rep) = 800 Hz and a peak power P-peak = 15 kW in combination with a 3-step-deposition technique. In a first set of experiments, the deposition process was optimised by investigating the crystallinity of ZnO films on silicon and polished stainless steel substrates. Here, the influence of the substrate temperature and of the oxygen partial pressure of the background gas were characterised by scanning electron microscopy and X-ray diffraction analyses. ZnO coated carbon fibres and conductive glass sheets were used to prepare photo anodes for dye-sensitised solar cells in order to investigate their suitability for energy conversion devices. To obtain a deeper insight of the electronic behaviour at the interface between ZnO and substrate I-V measurements were performed. (C) 2016 Elsevier B.V. All rights reserved.