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A dense NiO-Fe2O3 (NiFe) pellet has been developed as a potential anode-support for thin-film solid oxide fuel cells (SOFCs). However, preparation of dense NiFe is very challenging. Hole-formed NiFe pellets or porous NiFe pellets are frequently formed, which cannot be used as a support (substrate) for thin-film SOFCs. Therefore, this hole-formed NiFe support is simply wasted. In this report, we attempt to re-qualify this NiFe support to be a valuable substrate, which can be used for fabricating thin-film SOFCs. By deposition of smaller NiFe particles to cover the hole-formed NiFe support, the surface of this NiFe pellet is modified. Large holes on the surface disappear. The newly formed NiFe support can be used for fabricating a single cell with La0.9Sr0.1Ga0.8Mg0.2O3−δ as thin-film electrolyte operated at intermediate temperature. Maximum power density generated from this cell is 0.45, 0.86 and 1.28 W cm−2 at 873, 923 and 973 K, respectively.

The correlation between lattice strain induced by metal dispersion into grain and the cathodic overpotential is studied for increasing oxygen‐dissociation activity and improving power density of solid oxide fuel cells (SOFC) at decreased temperature. Pt or Au dispersion in Pr1.90Ni0.71Cu0.21Ga0.05O4+d (PNCG) is prepared and the 3D tensile strain is successfully induced after sintering by a mismatch in thermal expansion coefficient. Due to higher hardness and melting temperature, Pt dispersion into bulk of PNCG introduces larger tensile strain than that by Au at the same amount. In particular, at 1 mol% Pt dispersion, large tensile strain of 0.67% is induced. Overpotential of 1 mol% Pt‐PNCG cathode is 8 times smaller (35 mV) than that of PNCG (270 mV) at 800 °C and 300 mA cm−2, and it is found that the cathodic overpotential of PNCG is decreased with tensile strain on both Pt and Au dispersion. This cathodic activity enhancement appears to be related with the increased diffusivity of oxide ion in PNCG. In this study, cathodic overpotential is more significantly influenced by the induced tensile strain comparing with the intrinsic catalytic activity of the dispersed metal.

Summary: Introduction: Peripherally inserted central venous catheter (PICC) has a risk of causing phlebitis and thrombus occlusion. We coated the surfaces of the PICC with a specialized coating material (SEC-1) which may prevent thrombogenicity and phlebitis. This study aimed to evaluate SEC-1 coating PICCs using big animal. Methods: SEC-1 coating was used to both the internal and external surface of the catheter. In internal coating evaluation, the swine blood was filled up to 10 cm from the tip of the catheter into both non-coated and SEC-1-coated PICC (4Fr). Then we attempted to release the catheter occlusion at 5, 15 and 30 min while measuring the occlusion pressure by a digital pressure gauge. In external coating evaluation, after optimizing the phlebitis model using milk vein in swine, both PICCs inserted at a depth of 15 cm in the vein were forcibly withdrawn a distance of 5 cm and re-inserted 100 times. After 2days, we assessed inflammatory cell infiltration by histological evaluation. Result: The catheter occlusion release pressure at 5 min was measured at the non-coated: 2 and SEC-1-coated PICC:2 kPa. At 15 min, 7 and 4 kPa (p=0.38). At 30 min, 30 and 4 kPa (p=0.01). In external coating evaluation, there was no clear difference between the non-coated and the SEC-1-coated PICC in terms of inflammatory cell infiltration. Conclusion: The results of this study suggest that antithrombotic coating (SEC-1 coating) of PICC catheters may inhibit thrombogenicity. However, we were unable to confirm that it was effective in the control of phlebitis.

Abstract The addition of 3,3,3‐trifluoropropyl acetate (TFPA) to electrolyte in a Li‐ion rechargeable battery (LIB) provides a means for increasing the discharge performance at low temperatures as a result of the formation of a superior solid electrolyte interphase (SEI) on the graphite anode. For instance, the addition of 2 wt% TFPA to the electrolyte significantly increased the cycle stability and the discharge capacities at low temperatures (‐10°C) even at current rates of 3 C. The SEI films formed on the graphite anodes were characterized by electrochemical and spectroscopic techniques and by computational analysis. Although the formation of LiF on the anode has been recognized, present research revealed that the decomposition of TFPA on the anode surface resulted in the formation of an SEI layer consisting predominantly of organic fluorides. This layer suppressed the decomposition of the electrolyte resulting in a decreased anode impedance and an increase in cycle stability and discharge capacity at low temperatures.

Renewable hydrogen production is a sustainable method for the development of next-generation energy technologies. Utilising solar energy and photocatalysts to split water is an ideal method to produce hydrogen. In this review, the fundamental principles and recent progress of hydrogen production by artificial photosynthesis are reviewed, focusing on hydrogen production from photocatalytic water splitting using organic–inorganic composite-based photocatalysts.

Dye-sensitized photocatalytic hydrogen production using a boron-dipyrromethene (BODIPY) organic material having a pyridyl group at the anchor site was investigated. Phenyl, carbazole, and phenothiazine derivatives were introduced into BODIPY dyes, and their photocatalytic activities were examined. Identification was performed by nuclear magnetic resonance (NMR), infrared (IR), mass (MS) spectra, and absorption spectra, and catalyst evaluation was performed by using visible-light irradiation and photocatalytic hydrogen production and photocurrent. These dyes have strong absorption at 600–700 nm, suggesting that they are promising as photosensitizers. When the photocatalytic activity was examined, stable catalytic performance was demonstrated, and the activity of the Pt-TiO2 photocatalyst carrying a dye having a carbazole group was 249 μmol/gcat·h. Photocurrent measurements suggest that dye-sensitized photocatalytic activity is occurring. This result suggests that BODIPY organic materials with pyridyl groups as anchor sites are useful as novel dye-sensitized photocatalysts.

The title compound, C40H46N2 {systematic name: 12,30-diazaheptacyclo[21.13.1.15,19.16,18.110,14.124,36.128,32]dotetraconta-1(37),5(40),6(41),10(42),11,13,18,23,28,30,32(39),36(38)-dodecaene}, has syn–anti–syn geometry wherein the two outer [3.3]metacyclophane (MCP) moieties have a syn geometry, and contain the facing benzene and pyridine rings at dihedral angles of 26.26 (10) and 26.46 (10)°, respectively. The rings of the central [3.3]MCP unit are not parallel, but orientated at a slight angle of 2.66 (9)°. Three bridging methylene groups are disordered over two sets of sites in a 0.60:0.40 ratio. In the crystal, the molecules are linked by C—H...N interactions and intermolecular C—H...π short contacts, generating a three-dimensional network.

The title racemic spiro compound, C26H14Br2O, crystallizes with two independent molecules (A and B) in the asymmetric unit. The mean plane of the phenanthrene unit is twisted with respect to the mean plane of the fluorene unit by 82.38 (15) and 80.25 (5)° in molecules A and B, respectively. In the crystal, the A and B molecules are linked by a pair of C—H...O hydrogen bonds and a pair of short Br...O contacts [2.935 (2) Å], forming a centrosymmetric four-molecule unit. These units are linked by C—H...π interactions, forming ribbons propagating along the b-axis direction. The ribbons are linked by C—Br...π interactions, forming layers parallel to the ab plane.

In the title compound, C21H14N2O2S, a donor–acceptor type of benzo[b]phenothiazine (bpz) derivative, the thiazine ring adopts a boat conformation and the bond-angle sum at the N atom is 360.0°. The dihedral angle between the benzene ring and the naphthelene ring system fused to the thiazine ring is 32.76 (5)°. In the crystal, carboxylic-acid inversion dimers linked by pairs of O—H...O hydrogen bonds generate R22(8) loops. Aromatic π–π stacking [shortest centroid–centroid separaton = 3.5242 (13)Å] consolidates the structure and very weak C—H...O and C—H...N interactions also occur.

The title complex C42H48·2C6N4 {systematic name: heptacyclo[21.13.1.15,19.16,18.110,14.124,36.128,32]dotetraconta-1(37),5(40),6(41),10(42),11,13,18,23,28,30,32(39),36(38)-dodecaene–ethenetetracarbonitrile (1/2)}, consisting of four-layered [3.3]metacyclophane (MCP) with two tetracyanoethylene (TCNE) molecules, was grown from a mixture of MCP and TCNE in chloroform solution. The four-layered [3.3]MCP has an S-shaped structure in which three [3.3]MCP moieties take syn-(chair-boat), anti-(chair-boat) and syn-(chair-boat) conformations. The two outer [3.3]MCP moieties with syn geometry contain benzene rings with a tilt of 32.95 (7)°. The central [3.3]MCP moiety has an anti geometry, in which the two benzene rings are oriented parallel to each other at a transannular distance of 2.31 Å. The TCNE molecules are stacked on either side of the outer [3.3]MCP units at a distance of 3.19 Å on one side and 3.24 Å on the other, and showed 0.80:0.20 and 0.44:0.56 disorder, respectively.

Photocatalytic water splitting is one of the ideal methods for solving the global energy crisis and its associated environmental problems. In this study, the effect of altering the molecular structure of porphyrins was investigated to improve the water splitting activity of Zr-doped KTaO3 (KTa(Zr)O3) modified with porphyrin dyes. UV-vis spectra indicated that porphyrins with long alkoxy chains tended to form well-developed H-aggregates on the KTa(Zr)O3 surface. The photocatalytic activity of Pt-loaded KTa(Zr)O3 was improved by using porphyrins with longer alkoxy chains because of the improvement in the charge migration between porphyrin dye molecules. While the charge transfer between the inorganic semiconductor and porphyrin dye interface is important, it was found that the formation of H-aggregation was more effective in improving the water splitting activity of the porphyrin-modified photocatalysts.

Aqueous dual-ion batteries have good safety, environmental compatibility, and low cost due to the use of an aqueous electrolyte. However, water electrolysis occurs during charging at high potential, resulting in a poor cyclic stability of aqueous dual-ion batteries. Hence, novel anode materials are urgently needed to be developed for aqueous dual-ion batteries with low water electrolysis. A niobium-based binaryphase composite material is reported with a capacity of 135 mA h g-1 at a current density of 0.2 mA cm-2 and with excellent reversibility in the potential range of -1.3-0 V vs. Ag/AgCl. The activation energy of Li+ intercalation was obviously decreased because of the formation of an interface, which enhanced the Li+ intercalation reaction between FeNbO4 and MoNb12O33. In addition, the lower amount of Fe2+ in the lattice of MoNb12O33 caused localized compressive strain, which promoted fast Li+ diffusion in MoNb12O33. A full dual-ion battery of 3.0 V was constructed using the binary-phase niobium-based composite for the anode, and demonstrated a high cycle stability and an average coulombic efficiency of 91% over 300 cycles. Furthermore, considering both the electrolyte and electrode materials, the theoretical energy density of this dual-ion battery was estimated to be 250 W h kg-1, which is close to that of the current Li-ion rechargeable battery. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis from CO2 reduction is severely hampered by the kinetically challenging multi-electron reaction process. Oxygen vacancies (Vo) with abundant localized electrons have great potential to overcome this limitation. However, surface Vo usually have low concentrations and are easily oxidized, causing them to lose their activities. For practical application of CO2 photoreduction, fabricating and enhancing the stability of Vo on semiconductors is indispensable. Here we report the first synthesis of ultrathin WO[sub 3]⋅0.33H2O nanotubes with a large amount of exposed surface Vo sites, which can realize excellent and stable CO2 photoreduction to CH3COOH in pure water under solar light. The selectivity for acetum generation is up to 85%, with an average productivity of about 9.4 µmol g-1 h-1. More importantly, Vo in the catalyst are sustainable, and their concentration was not decreased even after 60 h of reaction. Quantum chemical calculations and in situ DRIFT studies revealed that the main reaction pathway might be CO2→ •COOH→ (COOH)2→ CH3COOH. [ABSTRACT FROM AUTHOR]

A series of alkylated indigos were synthesized. Alkylated indigos were characterized by NMR, mass spectrometry, absorption spectra, cyclic voltammetry, and density functional theory (DFT) calculations. Propyl and butyl group substituted indigo was most soluble in chloroform and 1,2-dicrolobenzene, and these solubility were 65-89 times increased as compared to the parent indigo. DFT calculations suggested that the presence of the alkyl chains at the 5.5'-position increases the energy of the highest occupied molecular orbital, while reducing the energy of the lowest unoccupied molecular orbital. This theoretical finding was in good agreement with the experimental results. Crystal structures obtained by X-ray diffraction showed one-dimensional pi-pi stacking. Alkylated molecules were converted to leuco structure, and these structures were then converted to the corresponding indigos in the film state. After deposition of the films on TiO2/FTO substrate, oxidative photocurrents were observed. [ABSTRACT FROM AUTHOR]

All possible pseudogeminal-, pseudoortho-, pseudometa-, and pseudopara-dibromo[3.3]paracyclophanes were synthesized by the (ptolylsulfonyl) methyl isocyanide (TosMIC) coupling method, and characterized by the aromatic proton signals of the 1H NMR spectra and finally by the X-ray crystal structure analyses of the pseudogeminal, pseudoortho, and pseudopara isomers. [ABSTRACT FROM AUTHOR]

Photocatalytic water splitting is one of the ideal methods for solving the global energy crisis and its associated environmental problems. In this study, the effect of altering the molecular structure of porphyrins was investigated to improve the water splitting activity of Zr-doped KTaO3 (KTa(Zr)O3) modified with porphyrin dyes. UV-vis spectra indicated that porphyrins with long alkoxy chains tended to form well-developed H-aggregates on the KTa(Zr)O3 surface. The photocatalytic activity of Pt-loaded KTa(Zr)O3 was improved by using porphyrins with longer alkoxy chains because of the improvement in the charge migration between porphyrin dye molecules. While the charge transfer between the inorganic semiconductor and porphyrin dye interface is important, it was found that the formation of H-aggregation was more effective in improving the water splitting activity of the porphyrin-modified photocatalysts. [ABSTRACT FROM AUTHOR]

Water splitting activity of a GaN:ZnO photocatalyst was improved by meso-hexakis(pentafluorophenyl) [26]hexaphyrin (3). The hexaphyrin (3) assisted the water splitting reaction over the GaN:ZnO photo-catalyst by using visible light energy around 600 nm. [ABSTRACT FROM AUTHOR]