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Syngas is traditionally used in industry for production of fuels in the kerosene, gasoline and diesel range via Fischer-Tropsch, for the manufacture of bulk chemicals like ammonia, methanol and dimethyl ether and for synthesis of a whole array of fine chemicals. The carbon monoxide/hydrogen ratio of the syngas is an important design variable to maximize production of these compounds. Therefore, the search of effective processes that enable said ratio adjustment as well as individual compound purification is an essential and ongoing effort for industry. In this work, we propose a development of a zeolite-based separation process to obtain carbon dioxide-neutral fuels and chemicals. The process designed is based on gas uptake and release, combining separation efficiency with low separation costs. Calculation of separation behavior has been done for mixtures generated by plasmolysis of CO2. Carbon dioxide dissociation into CO and O2 and as a result a mixture of carbon monoxide, oxygen and a residual carbon dioxide is obtained. Therefore, the purification of CO becomes necessary. Here we provide a purification process design based in multicomponent adsorption and separation in commercial available zeolites. The process identifies NaX and NaY as the most suitable zeolites for separation in a wide range of operating conditions.

Photoelectrochemical (PEC) reactors based on polymer electrolyte membrane (PEM) electrolyzers are an attractive alternative to improve scalability compared to conventional monolithic devices. To introduce narrow band gap photoabsorbers such as BiVO4in PEM–PEC system requires cost-effective and scalable deposition techniques beyond those previously demonstrated on monolithic FTO-coated glass substrates, followed by the preparation of membrane electrode assemblies. Herein, we address the significant challenges in coating narrow band gap metal-oxides on porous substrates as suitable photoelectrodes for the PEM–PEC configuration. In particular, we demonstrate the deposition and integration of W-doped BiVO4on porous conductive substrates by a simple, cost-effective, and scalable deposition based on the SILAR (successive ionic layer adsorption and reaction) technique. The resultant W-doped BiVO4photoanode exhibits a photocurrent density of 2.1 mA·cm–2, @ 1.23 V vs RHE, the highest reported so far for the BiVO4on any porous substrates. Furthermore, we integrated the BiVO4on the PEM–PEC reactor to demonstrate the solar hydrogen production from ambient air with humidity as the only water source, retaining 1.55 mA·cm–2, @ 1.23 V vs RHE. The concept provides insights into the features necessary for the successful development of materials suitable for the PEM–PEC tandem configuration reactors and the gas-phase operation of the reactor, which is a promising approach for low-cost, large-scale solar hydrogen production.

Electrodeposited cobalt phosphate has been reported as a valid alternative to noble metals as an electrocatalyst for the Oxygen Evolution Reaction (OER). In parallel, Atomic Layer Deposition (ALD) is increasingly being used in (photo)electrocatalytic applications. In this contribution we report on the electrocatalytic activity towards OER of ALD-prepared cobalt phosphate thin films. The selected ALD approach enables tuning of the Co-to-P atomic ratio, which is found to significantly affect the activity of the prepared electrocatalyst. Specifically, concurrently with a Co-to-P ratio increase from 1.6 to 1.9, the current density for OER increases from 1.77 mA/cm2 at 1.8 V vs. RHE (Reversible Hydrogen Electrode) to 2.89 mA/cm2 at 1.8 V vs. RHE. Moreover the sample with a Co-to-P ratio of 1.9 has superior performance when compared to electrodeposited cobalt phosphate thin films reported in the literature. Keywords: Atomic layer deposition, Cobalt phosphate, Electrocatalysis, Oxygen evolution reaction

The development of efficient and stable earth-abundant water oxidation catalysts is vital for economically feasible water-splitting systems. Cobalt phosphate (CoPi)-based catalysts belong to the relevant class of nonprecious electrocatalysts studied for the oxygen evolution reaction (OER). In this work, an in-depth investigation of the electrochemical activation of CoPi-based electrocatalysts by cyclic voltammetry (CV) is presented. Atomic layer deposition (ALD) is adopted because it enables the synthesis of CoPi films with cobalt-to-phosphorous ratios between 1.4 and 1.9. It is shown that the pristine chemical composition of the CoPi film strongly influences its OER activity in the early stages of the activation process as well as after prolonged exposure to the electrolyte. The best performing CoPi catalyst, displaying a current density of 3.9 mA cm-2 at 1.8 V versus reversible hydrogen electrode and a Tafel slope of 155 mV/dec at pH 8.0, is selected for an in-depth study of the evolution of its electrochemical properties, chemical composition, and electrochemical active surface area (ECSA) during the activation process. Upon the increase of the number of CV cycles, the OER performance increases, in parallel with the development of a noncatalytic wave in the CV scan, which points out to the reversible oxidation of Co2+ species to Co3+ species. X-ray photoelectron spectroscopy and Rutherford backscattering measurements indicate that phosphorous progressively leaches out the CoPi film bulk upon prolonged exposure to the electrolyte. In parallel, the ECSA of the films increases by up to a factor of 40, depending on the initial stoichiometry. The ECSA of the activated CoPi films shows a universal linear correlation with the OER activity for the whole range of CoPi chemical composition. It can be concluded that the adoption of ALD in CoPi-based electrocatalysis enables, next to the well-established control over film growth and properties, to disclose the mechanisms behind the CoPi electrocatalyst activation.

Ammonia is an important precursor of fertilizers, as well as a potential carbon-free energy carrier. Nowadays, ammonia is synthesized via the Haber-Bosch process, which is a capital- and energy-intensive process with an immense CO2 footprint. Thus, alternative processes for the sustainable and decentralized ammonia production from N2 and H2O using renewable electricity are required. The key challenges for the realization of such processes are the efficient activation of the N2 bond and selectivity toward NH3. In this contribution, we report an all-electric method for sustainable ammonia production from nitrogen and water using a plasma-activated proton conducting solid oxide electrolyzer. Hydrogen species produced by water oxidation over the anode are transported through the proton conducting membrane to the cathode where they react with the plasma-activated nitrogen toward ammonia. Ammonia production rates and Faradaic efficiencies up to of 26.8 nmol of NH3 s-1 cm-2 and 88%, respectively, were achieved.

Silver orthophosphate is a highly promising visible light photocatalyst with high quantum yield for solar driven water oxidation. Recently, the performance of this material has been further enhanced using facet-controlled synthesis. The tetrahedral particles with {111} exposed facets demonstrate higher photocatalytic performance than the cubic particles with {100} exposed facets. However, the reason behind this large difference in photocatalytic performance is still not understood. In this work, we study the free charge carrier dynamics, such as mobility, lifetime, and diffusion lengths, for the {111}-faceted tetrahedral and the {100}-faceted cubic particles using time-resolved microwave conductivity measurements. An order of magnitude higher charge carrier mobility and diffusion length are found for the tetrahedral particles as compared to the cubic particles. The differences in crystal structure, surface composition, and optical properties are investigated in order to understand how these properties impact the charge carrier dynamics and the photocatalytic performance of differently faceted particles.

Silver orthophosphate is a highly promising visible light photocatalyst with high quantum yield for solar driven water oxidation. Recently, the performance of this material has been further enhanced using facet-controlled synthesis. The tetrahedral particles with {111} exposed facets demonstrate higher photocatalytic performance than the cubic particles with {100} exposed facets. However, the reason behind this large difference in photocatalytic performance is still not understood. In this work, we study the free charge carrier dynamics, such as mobility, lifetime, and diffusion lengths, for the {111}-faceted tetrahedral and the {100}-faceted cubic particles using time-resolved microwave conductivity measurements. An order of magnitude higher charge carrier mobility and diffusion length are found for the tetrahedral particles as compared to the cubic particles. The differences in crystal structure, surface composition, and optical properties are investigated in order to understand how these properties impact the charge carrier dynamics and the photocatalytic performance of differently faceted particles.

The development of nonprecious metal electrocatalysts for polymer-electrolyte membrane (PEM) water electrolysis is a milestone for the technology, which currently relies on rare and expensive platinum-group metals. Half-cell measurements have shown iron phosphide materials to be promising alternative hydrogen evolution electrocatalysts, but their realistic performance in flow-through devices remains unexplored. To fill this gap, we report herein the activity and durability of FeP nanocatalyst under application-relevant conditions. Our facile synthesis route proceeds via impregnation of an iron complex on conductive carbon support followed by phosphorization, giving rise to highly crystalline nanoparticles with predominantly exposed [010] facets, which accounts for the high electrocatalytic activity. The performance of FeP gas diffusion electrodes toward hydrogen evolution was examined under application-relevant conditions in a single cell PEM water electrolysis at 22 °C. The FeP cathode exhibited a current density of 0.2 A cm–2 at 2.06 V, corresponding to a difference of merely 0.07 W cm–2 in power input as compared to state-of-the-art Pt cathode, while outperforming other nonprecious cathodes operated at similar temperature. Quantitative product analysis of our PEM device excluded the presence of side reactions and provided strong experimental evidence that our cell operates with 84–100% Faradaic efficiencies and with 4.1 kWh Nm–3 energy consumption. The FeP cathodes exhibited stable performance of over 100 h at constant operation, while their suitability with the intermittency of renewable sources was demonstrated upon 36 h operation at variable power inputs. Overall, the performance as well as our preliminary cost analysis reveal the high potential of FeP for practical applications.

Carbon dioxide and steam solid oxide co-electrolysis is a key technology for exploiting renewable electricity to generate syngas feedstock for the Fischer-Tropsch synthesis. The integration of this process with methane partial oxidation in a single cell can eliminate or even reverse the electrical power demands of co-electrolysis, while simultaneously producing syngas at industrially attractive H2/CO ratios. Nevertheless, this system is rather complex and requires catalytically active and coke tolerant electrodes. Here, we report on a low-substitution rhodium-titanate perovskite (La0.43Ca0.37Rh0.06Ti0.94O3) electrode for the process, capable of exsolving high Rh nanoparticle populations, and assembled in a symmetrical solid oxide cell configuration. By introducing dry methane to the anode compartment, the electricity demands are impressively decreased, even allowing syngas and electricity cogeneration. To provide further insight on the Rh nanoparticles role on methane-to-syngas conversion, we adjusted their size and population by altering the reduction temperature of the perovskite. Our results exemplify how the exsolution concept can be employed to efficiently exploit noble metals for activating low-reactivity greenhouse gases in challenging energy-related applications.

We recently described the use of Ti(0) microfibers as an anodization substrate for the preparation of TiO2 nanotubes arrays as porous photoanodes. Here, we report the use of these fibers as a scaffold to build porous photoanodes based on a WO3/BiVO4 heterojunction. The obtained photoelectrodes show promising results under visible light irradiation for water oxidation both in a typical liquid-phase photoelectrochemical setup and in a gas phase reactor (developed in-house) based on a polymeric electrolyte membrane. Keywords: Photoelectrochemical H2 production, Polymeric electrolyte membrane, Gas phase water-splitting, WO3/BiVO4 photoanode, Visible light

The transformation of sunflower oil (SO) and waste cooking oil (WCO) into green diesel over co-precipitated nickel&ndash, zirconia catalysts was studied. Two series of catalysts were prepared. The first series included catalysts with various Ni loadings prepared using zirconium oxy-chloride, whereas the second series included catalysts with 60&ndash, 80 wt % Ni loading prepared using zirconium oxy-nitrate as zirconium source. The catalysts were characterized and evaluated in the transformation of SO into green diesel. The best catalysts were also evaluated for green diesel production using waste cooking oil. The catalysts performance for green diesel production is mainly governed by the Ni surface exposed, their acidity, and the reducibility of the ZrO2. These characteristics depend on the preparation method and the Zr salt used. The presence of chlorine in the catalysts drawn from the zirconium oxy-chloride results to catalysts with relatively low Ni surface, high acidity and hardly reduced ZrO2 phase. These characteristics lead to relatively low activity for green diesel production, whereas they favor high yields of wax esters. Ni-ZrO2 catalysts with Ni loading in the range 60&ndash, 80 wt %, prepared by urea hydrothermal co-precipitation method using zirconium oxy-nitrate as ZrO2 precursor salt exhibited higher Ni surface, moderate acidity, and higher reducibility of ZrO2 phase. The latter catalysts were proved to be very promising for green diesel production.

Solar hydrogen is a promising sustainable energy vector, and steady progress has been made in the development of photoelectrochemical (PEC) cells. Most research in this field has focused on using acidic or alkaline liquid electrolytes for ionic transfer. However, the performance is limited by (i) scattering of light and blocking of catalytic sites by gas bubbles and (ii) mass transport limitations. An attractive alternative to a liquid water feedstock is to use the water vapor present as humidity in ambient air, which has been demonstrated to mitigate the above problems and can expand the geographical range where these devices can be utilized. Here, we show how the functionalization of porous TiO2 and WO3 photoanodes with solid electrolytes - proton conducting Aquivion and Nafion ionomers - enables the capture of water from ambient air and allows subsequent PEC hydrogen production. The optimization strategy of photoanode functionalization was examined through testing the effect of ionomer loading and the ionomer composition. Optimized functionalized photoanodes operating at 60% relative humidity (RH) and Tcell = 30-70 °C were able to recover up to 90% of the performance obtained at 1.23 V versus reverse hydrogen electrode (RHE) when water is introduced in the liquid phase (i.e., conventional PEC operation). Full performance recovery is achieved at a higher applied potential. In addition, long-term experiments have shown remarkable stability at 60% RH for 64 h of cycling (8 h continuous illumination-8 h dark), demonstrating that the concept can be applicable outdoors.

Alcohol electrolysis using polymeric membrane electrolytes is a promising route for storing excess renewable energy in hydrogen, alternative to the thermodynamically limited water electrolysis. By properly choosing the ionic agent (i.e. H+ or OH−) and the catalyst support, and by tuning the catalyst structure, we developed membrane-electrode-assemblies which are suitable for cost-effective and efficient alcohol electrolysis. Novel porous electrodes were prepared by Atomic Layer Deposition (ALD) of Pt on a TiO2-Ti web of microfibers and were interfaced to polymeric membranes with either H+ or OH− conductivity. Our results suggest that alcohol electrolysis is more efficient using OH− conducting membranes under appropriate operation conditions (high pH in anolyte solution). ALD enables better catalyst utilization while it appears that the TiO2-Ti substrate is an ideal alternative to the conventional carbon-based diffusion layers, due to its open structure. Overall, by using our developmental anodes instead of commercial porous electrodes, the performance of the alcohol electrolyser (normalized per mass of Pt) can be increased up to ∼30 times.

A novel photoelectrochemical (PEC) cell design is proposed and investigated for H-2 production with gaseous reactants. The core of the cell is a membrane electrode assembly (MEA) that consists of a TiO2 nanotube arrays photoanode, a Pt/C cathode, a Pt/C reference electrode and a proton conducting polymeric electrolyte membrane (PEM), which serves both as compact reactor for water splitting and as gas separator. The design is inspired by PEM electrolysis technology and modified appropriately to allow light irradiation and to host a third electrode compartment, which enables the use of a hydrogen reference electrode. The titanium dioxide nanotube arrays (TNTAs) photoanodes were synthetized, for the first time, on a Ti-web of microfiber substrates by electrochemical anodization. The performance of TNTAs/Ti-web photoanodes were evaluated in both gaseous (i.e. PEM-PEC cell) and liquid media (conventional PEC cell). Due to the presence of the PEM-PEC reference electrode comparison of the results was possible. Gas phase operation with either He or air as carrier exhibits very promising photoefficiency in comparison with conventional PEC cells. Additionally the performance of our PEM-PEC cell was also investigated for simultaneous anodic air treatment and cathodic hydrogen evolution. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Conventional photoelectrochemical (PEC) cells are based on planar photoelectrodes supported on glass substrates and liquid electrolytes. Only few recent studies have examined an alternative PEC design which is robust and scalable, where the key elements are polymeric electrolyte membranes and porous photoelectrodes. This work aims to give further insights on the operation of such cells utilizing titania photoelectrodes and proton and hydroxide ion conducting membranes. Two families of photoelectrodes were developed on Ti porous substrate; TiO2 nanotubes grown by anodization and subsequent oxygen annealing, and TiO2 layers developed under oxygen annealing. Initial screening of the photoanodes for water splitting and (poly)alcohol photo-oxidation took place in conventional PEC cells. We found that the annealing temperature affects the performance of the photoanodes, evidenced by a monotonic increase in the activity for water photo-oxidation with increasing annealing temperature. Moreover it was demonstrated that anatase phase is predominantly active for the (poly)alcohol electro-oxidation, while there is a synergy between rutile and anatase which is beneficial for water splitting. In addition, the most promising photoanodes for water splitting were evaluated in our polymeric electrolyte membrane photoelectrochemical(PEM-PEC) cell during gas phase operation. It was found that PEM-PEC operation is more efficient when OH- conducting membranes are used, while the nature of the carrier gas does not significantly influence the activity. Overall, PEM-PEC operation is more promising than conventional PEC in both acidic and alkaline media, since comparable (or even at some cases higher) photocurrents were obtained while liquid pumping systems are not required for PEM-PEC devices.

A novel photoelectrochemical (PEC) cell design is proposed and investigated for H2 production with gaseous reactants. The core of the cell is a membrane electrode assembly (MEA) that consists of a TiO2 photoanode of nanotube arrays, a Pt/C counter and reference electrodes and a polymeric electrolyte membrane (PEM) with proton conductivity, which serves both as compact reactor for water splitting and as gas separator. The design was inspired by PEM electrolysis technology and modified appropriately for allowing illumination and it is also equipped with a third compartment which enables the use of a hydrogen reference electrode.Photoanodes of titania nanotube arrays, TNTAs, were developed, for the first time, on a Ti-web of microfiber substrates, by electrochemical anodization. The performance of TNTAs/Ti-web photoanodes were evaluated in both gaseous and liquid reactants. Due to the presence of reliable reference electrode in gas phase direct comparison of the results was possible. Gas phase operation with He or Air as carrier gases and only 2.5% of water content exhibits very promising photoefficiency in comparison with conventional PEC cells.

Lung cancer is a stressful condition for both patient and family. The anxiety and pain accompanying cancer and its treatment have a significant negative influence on the patient’s quality of life. The aim of this study was to investigate the correlation between anxiety, pain, and perceived family support in a sample of lung cancer patients. The sample consisted of a total of 101 lung cancer outpatients receiving treatment at the oncology department of a general hospital. Anxiety, pain (severity and impact on everyday life), and perceived family support were assessed using Spielberger’s State-Trait Anxiety Inventory, the Brief Pain Inventory, and the Family Support Scale, respectively. Statistical analyses revealed correlations between anxiety, pain, and family support as perceived by the patients. The intensity of pain had a positive correlation with both state and trait anxiety and a negative correlation with family support. Anxiety (state and trait) had a significant negative correlation with family support. In conclusion, high prevalence rates of anxiety disorders were observed in lung cancer patients. Females appeared more susceptible to anxiety symptoms with a less sense of family support. A negative correlation was evidenced between family support and anxiety and a positive one between anxiety and pain.

Background/Aims: The purpose of the study is to report two long-term survivors with ovarian carcinosarcomas, which are rare intrapelvic malignancies with unfavorable prognosis. Methods: Two middle-aged women with palpable abdominal tumors underwent complete cytoreductive surgery and no macroscopic tumor was left behind. Early postoperative intraperitoneal chemotherapy with doxorubicin was used as an adjuvant treatment. Results: The patients are disease-free 2 and 3 years, respectively after the initial therapy. Conclusion: Complete cytoreduction combined with early postoperative intraperitoneal chemotherapy seems to be an effective treatment for ovarian carcinosarcoma with peritoneal spread. Further studies are required to define the value of intraperitoneal chemotherapy in ovarian carcinosarcoma.

The purpose of the study is to report two long-term survivors with ovarian carcinosarcomas, which are rare intrapelvic malignancies with unfavorable prognosis.Two middle-aged women with palpable abdominal tumors underwent complete cytoreductive surgery and no macroscopic tumor was left behind. Early postoperative intraperitoneal chemotherapy with doxorubicin was used as an adjuvant treatment.The patients are disease-free 2 and 3 years, respectively after the initial therapy.Complete cytoreduction combined with early postoperative intraperitoneal chemotherapy seems to be an effective treatment for ovarian carcinosarcoma with peritoneal spread. Further studies are required to define the value of intraperitoneal chemotherapy in ovarian carcinosarcoma.