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Photoelectrochemical (PEC) water splitting supplies an environmentally friendly, sustainable approach to generating renewable hydrogen fuels. Oxides semiconductors, e.g. TiO2, BiVO4, and Fe2O3, have been widely developed as photoelectrodes to demonstrate the utility in PEC systems. Even though significant effort has been made to increase the PEC efficiency, these materials are still far from practical applications. The main issue of metal oxides is the wide bandgap energy that hinders effective photons harvesting from sunlight. In solar spectrum, over 40% of the energy is located in the near-infrared (NIR) region. Developing sophisticated PEC systems that can be driven by NIR illumination is therefore essential. This review gives a concise overview on PEC systems based on the use of NIR-driven photoelectrodes. Promising candidates as efficient yet practical NIR-responsive photoelectrodes are suggested and discussed. Future outlooks on the advancement of PEC water splitting are also proposed.

In this work, defect-free and high mechanical strength nickel films are deposited at a high growth rate using a high concentration sulfamate bath for applications in fabrication of MEMS components. Effects of the applied current density on the morphology, average grain size, Vickers hardness, micro-mechanical property, and thickness distribution are studied. The average grain size is refined to a minimum value when the current density is increased from 10 to 20 mA/cm2. The finest grain size obtained is 349.8 nm. The grain refinement effect is a result of the promoted nucleation rate as the applied current density increased. When the current density is beyond 20 mA/cm2, overpotential of the nickel reduction reaction is lowered because of the promoted hydrogen evolution and causes coarsening of the average grain size. The film electroplated at 20 mA/cm2 shows a high growth rate at 0.296 μm/min, the highest Vickers hardness at 371 HV, and the yield stress evaluated by micro-compression test is 1.3 GPa. Relationship between the average grain size and the applied current density follows the Hall-Petch relationship well.

In this research, micro-bending tests of electrodeposited gold with various crystal structure were conducted using micro-cantilever specimens with dimensions at 10 μm × 10 μm × 50 μm for design of gold-based movable structures in MEMS devices. The gold film fabricated by pulse-current electrodeposition with a sulfite-based gold electrolyte (PE-Su) had the finest average grain size, which was at 15.5 nm. The PE-Su gold micro-cantilever showed ductile deformation behavior and the highest yield stress, which was at 800 MPa, because of the grain boundary strengthening mechanism also known as the Hall-Petch relationship. The gold film fabricated by constant-current electrodeposition with a cyanide-based gold electrolyte (CE-Cy) had an average grain size at 17.6 nm. The CE-Cy gold micro-cantilever showed brittle fracture and the yield stress at 480 MPa. The brittle fracture was suggested to be a result of the columnar texture structure in the CE-Cy gold film.

In this study, an electroless deposition method including catalyzation in supercritical carbon dioxide (sc-CO2) and plating in sc-CO2 emulsified electrolyte was applied in metallization of Nylon 6,6 textile. In order to demonstrate the effects of the sc-CO2, the catalyzation was conducted either by the conventional method or the supercritical CO2 catalyzation (SCC) method with bis (2,4-pentandionato)-palladium. After the catalyzation process, either the conventional electroless plating or the electroless plating with supercritical CO2 emulsified electrolyte (ELP-SCE) was performed. Surface of the Ni-P coatings on the Nylon 6,6 was observed by an optical microscope and a scanning electron microscope. The Ni-P coating by the conventional catalyzation and the conventional electroless plating showed some cracks, nodules and rough structure. The Ni-P coating by the SCC and the conventional electroless plating showed smooth Ni-P coating on the surface of each fibers and had some peeled-off parts. On the other hand, uniform Ni-P coating on the surface of each fibers was obtained by the SCC and the ELP-SCE. These results demonstrated that the SCC is effective to impregnate Pd catalysts into the fibers, and the ELP-SCE can inhibit the nodule growth of the Ni-P. Thus, the proposed method can metallize the surface of each Nylon 6,6 fibers and has potential to give some functions on textiles.

In this study, an electroless plating method involved Pt catalyzation in supercritical carbon dioxide (sc-CO2) and conventional Pt electroless plating was used for the metallization of polyamide 6,6 (PA66) textiles. The catalyzation was conducted either by conventional method at atmospheric pressure or in sc-CO2 with bis (2,4-pentandionato)-platinum. After the catalyzation process, the conventional Pt electroless plating method was performed for the Pt catalyzed PA66 textiles. Surface of the Pt coated PA66 was observed by an optical microscope and a scanning electron microscope. The Pt coating by the conventional catalyzation had a rough surface, and the surface did not show the textile outline because of the dissolution of the textile in the conventional catalyzation solution. The textile metallized by the sc-CO2 catalyzation showed a metallic bright coating, and the Pt coating was observed on the surface of each fiber. These results indicate that the sc-CO2 catalyzation is a promising method to catalyze the PA66 textile. Display Omitted Metallization of polyamide 66 (PA66) using supercritical CO2 (sc-CO2) was reported.Pt was used as the catalyst and coating to improve the biocompatibility.Pt catalyst seeds were formed by sc-CO2 catalyzation (SCC).Uniform Pt coating was formed by SCC follow by conventional electroless plating.The Pt coating was bright, defect-free and still showed outline of the PA66 fibers.

Novel three-dimensional hierarchical heterostructures composed of two-dimensional SnS 2 nanoflakes and zero-dimensional SnO 2 nanoparticles were fabricated via a one-step hydrothermal method. Size of the heterostructures was ca. 2 μm in diameter, and individual SnS 2 nanoflakes with thickness of ca. 150 nm were connected to central core of the heterostructures. The SnO 2 nanoparticles in a diameter of ca. 5 nm uniformly covered entire surface of the SnS 2 nanoflakes. Moreover, both of these structures were highly crystalline. Meanwhile, amorphous carbon was formed within the heterostructures. The SnS 2 /SnO 2 /C hierarchical heterostructures had a high initial specific reversible capacity of 1065.7 mAh g −1 , stable cycling stability of 638 mAh g −1 after 30 cycles, and superior rate capability of 550.8 mAh g −1 at 1C rate. These SnS 2 /SnO 2 /C hierarchical heterostructures showed better performance than individual SnS 2 and SnO 2 nanomaterials, and the performance was even higher than the graphene–SnS 2 and graphene–SnO 2 nanohybrid materials. This is attributed to a synergistic effect of high surface area, which is provided by the unique SnS 2 internal nanoflake layered structures decorated with ultra-fine SnO 2 nanoparticles, and an effective beneficial buffer matrix to accommodate the large volume change upon cycling, which is caused by the side-products such as Li 2 S or Li 2 O. The SnS 2 nanoflake was deduced to play a similar role as graphene material, since both possess 2D conducting layer structures. The uniform carbon dispersion within the structures also stabilizes the structures and improves electrical conductivity of the hierarchical heterostructures.

We report an unconventional electrochemical spontaneous oscillation of current in Ti anodization by adding deep eutectic solvent (DES) of 2–10% to a fluoride-containing electrolyte; nanobamboos (NBs), i.e., nanotubes decorated with periodic exterior rings, were formed by the DES-assisted anodization. Spontaneous formation of NBs occurred upon application of a constant 20 V voltage, together with a self-induced current oscillation that corresponds well to the NB structures. The initial voltage must be higher than a threshold of approximately 14 V to induce the self-organization of the NBs. Once a dense layer of TiO2 is formed at 10 V or lower, formation of the NBs is suppressed even when a higher voltage (above 15 V) is applied. The NBs formed with the spontaneous current oscillation were densely packed (ca. 1.54 × 1010 cm−2) with each NB possessing many rings spaced 20–35 nm apart. The thickness of each ring was ca. 10 nm. By increasing the DES concentration to 10 wt%, the diameter of the NBs increased from 45 to 110 nm and their growth rate increased from 0.16 to 0.3 μm/h. The spontaneous current oscillation we observed differs from the conventional electrochemical oscillation because (1) oscillation period is quite long (7 min) and (2) the oscillation results in the periodic modulation of TiO2 NBs. The self-organized nanobaoboos were characterized for various anodization conditions, and a mechanism was proposed with the basis of the high conductivity and high viscosity of DES.

The crystal structures of N-o-hydroxybenzimido-meso-tetraphenylporphyrinatozinc(II) toluene solvate [Zn(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 4·C6H5CH3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatonickel(II) chloroform solvate [Ni(N-NCO(o-OH)C6H4-tpp)·0.6CHCl3; 5·0.6 CHCl3], N-o-hydroxybenzimido-meso-tetraphenylporphyrinatocopper(II) toluene solvate [Cu(N-NCO(o-OH)C6H4-tpp)·C6H5CH3; 6·C6H5CH3] and N-o-oxido-benzimido-meso-tetraphenylporphyrinato(-κ4,N1,N2,N3,N5,κO2) manganese (III) methylene chloride·methanol solvate [Mn(N-NCO(o-O)C6H4-tpp)·CH2Cl2·MeOH; 8·CH2Cl2·MeOH] were established. The coordination sphere around Zn2+ ion in 4·C6H5CH3, (or Ni2+ ion in 5·0.6 CHCl3 or Cu2+ ion in 6·C6H5CH3) is a distorted square planar (DSP) whereas for Mn3+ in 8·CH2Cl2·MeOH, it is a distorted trigonal bipyramid (DTBP) with O(1), N(1) and N(3) lying in the equatorial plane for 8·CH2Cl2·MeOH. The g value of 8.27 measured from the parallel polarization of X-band EPR spectra at 293 K is consistent with the high-spin mononuclear manganese(III) (S = 2) in 8. The magnitude of axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) in 8 was determined approximately as 3.0 cm−1 by the paramagnetic susceptibility measurements and conventional EPR spectroscopy.

The coordinating properties of N - o -chlorobenzamido- meso -tetraphenylporphyrin ( N -NHCO( o -Cl)C 6 H 4 -Htpp; 11 ) have been investigated for the Zn 2+ ion. Insertion of Zn results in the formation of the zinc complex Zn( N -NCO( o -Cl)C 6 H 4 -tpp)(MeOH) · MeOH ( 12 · MeOH). The diamagnetic 12 · MeOH can be transformed into the diamagnetic Zn( N -NHCO( o -Cl)C 6 H 4 -tpp)Cl · CH 2 Cl 2 ( 13 · CH 2 Cl 2 ) in a reaction with aqueous hydrogen chloride (2%). X-ray structures for 12 · MeOH and 13 · CH 2 Cl 2 have been determined. The coordination sphere around the Zn 2+ ion in 12 · MeOH is a distorted trigonal bipyramid with N(2), N(4) and O(2) lying in the equatorial plane, whereas for the Zn 2+ ion in 13 · CH 2 Cl 2 , it is a square-based pyramid in which the apical site is occupied by the Cl(1) atom.

Helicobacter pylori is an important risk factor of duodenal ulcer (DU). Although many virulence factors of H. pylori have been identified, few have been reported to show an association with the pathogenesis of DU. The aims of this study were to identify H. pylori antigens showing a high seropositivity in DU and to develop a platform for rapid and easy diagnosis for DU. Because DU and gastric cancer (GC) are considered clinical divergent gastroduodenal diseases, we compared two-dimensional immunoblots of an acid-glycine extract of an H. pylori strain from a patient with DU probed with serum samples from 10 patients with DU and 10 with GC to identify DU-related antigens. Of the 11 proteins that were strongly recognized by serum IgG from DU patients, translation elongation factor EF-G (FusA), catalase (KatA), and urease alpha subunit (UreA) were identified as DU-related antigens, showing a higher seropositivity in DU samples (n = 124) than in GC samples (n = 95) (FusA, 70.2 versus 45.3%; KatA, 50.8 versus 41.1%; UreA, 44.4 versus 27.4%). In addition, we found that the use of multiple antigens improved the discrimination between patients with DU and those with GC as the odds ratios increased from 1.82 (95% confidence interval (CI), 0.79-4.21; p = 0.1607) for seropositivity for FusA, KatA, or UreA alone to 4.95 (95% CI, 2.05-12.0; p = 0.0004) for two of the three antigens and to 5.71 (95% CI, 1.86-17.6; p = 0.0024) for all three antigens. Moreover a protein array containing the three DU-related antigens was developed to test the idea of using multiple biomarkers in diagnosis. We conclude that FusA, KatA, and UreA are DU-related antigens of H. pylori, and the combination of these on a protein array provided a rapid and convenient method for detecting serum antibody patterns of DU patients.