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Recently, there has been an increased interest in polymer electrolyte membrane fuel cells (PEMFCs). PEMFCs have energy conversion efficiencies as high as 80%. However, the durability of PEMFCs has been recently recognized as one of the most important issues to be addressed before the commercialization of PEMFCs. Pt surface area loss due to carbon corrosion and Pt nanoparticle (NP) dissolution from the carbon support and/or aggregation on the carbon support are considered one of the major problems to address. Carbon black (CB) is normally used as a support material for the Pt catalyst to maximize the mass activity of the catalyst. However, the oxidized sites of the CB accelerate the degradation of the support material for Pt NPs. The CB will oxidize at edge sites because polar functional groups can form at those sites. The polar functional groups will be further oxidized and finally corroded away. Recently, carbon nanotubes (CNTs) have been proposed as promising support materials for Pt NPs because the CNT supports exhibit high conductivity and mass transport capability as well as high chemical stability. However, there are no novel binding sites for adsorbing Pt ions on the CNT surfaces, although the surfaces of CNT are composed of non-oxidized graphitic carbon. Usually, functional groups are generated on the external walls to make the binding sites for Pt source using harsh oxidative treatments, such as refluxing in HNO3 or H2SO4-HNO3. However, the treated CNT surfaces will suffer serious carbon corrosion under conditions such as low pH, high potential, high humidity, and high temperature (~80 °C). A new methodology for the deposition of catalyst NPs on CNT surfaces should be developed that satisfies both requirements for high NP dispersion and chemical stability. Recently, nanocrystalline TiO2 as a catalyst support has received increasing attention due to its inherent stability in the electrochemical environment, its commercial availability, and its enhancement of electrocatalytic activity due to its corrosion resistance and the synergistic effect between NPs and TiO2. We considered the preparation of PtPb/TiO2 on cup-stacked carbon nanotube (CSCNT) to enhance the oxygen reduction reaction (ORR). CSCNTs are tubular carbon nanostructures with a stacked cup arrangement of graphene layers. Therefore, the edges of the graphene layers are densely exposed on the surface of the CSCNT. The graphene edges are used as scaffolds to thoroughly coat the CSCNT surface with TiO2 layers. The PtPb ordered intermetallic NP electrocatalyst was selectively deposited on the TiO2 layers. The CSCNT functions as an electron conducting path. Recently, we reported that PtPb/TiO2 showed enhancement of electrocatalytic activity for the ORR [1]. The nature of the support, the composition of catalytic sites, the sites’ interaction with the support, and the electronic structure of the catalytic sites all most likely influenced the observed electrochemical behavior. In this study, PtPb NPs were chemically deposited on small, thin TiO2 layers that were prepared on CSCNTs. The unique catalytic property of PtPb ordered intermetallic NPs and the strong interaction between PtPb NPs and TiO2 layers successfully achieved the enhancement of ORR in acidic aqueous solutions. The improved ORR performance of PtPb NPs/TiO2/CSCNT is not an effect of the CSCNT support material. Rather, the higher performance is due to the interaction between PtPb NPs and TiO2. The CSCNTs can provide a large amount of structure to PtPb NPs on TiO2 on the CSCNT surface. [1] T. Gunji, G. Saravanan, T. Tanabe, T. Tsuda, M. Miyauchi, G. Kobayashi, H. Abe, F. Matsumoto, Catalysis Science and Technology, 2014, 4, 1436.

In our previous study, we showed that the addition of 4-pyridinecarboxylic acid hydrazide (4-PCAH) to an EMIC/AlCl3/toluene mixture improved the brightness of the deposited Al film [1]. The prepared Al films clearly reflect the characters on the surface so that the characters can be read. The reflectivity of the Al surface prepared with EMIC/AlCl3/toluene/4-PCAH was 84% at 450 nm; to the best of our knowledge, this is the highest value achieved. In this study, to elucidate why the addition of 4-PCAH to the EMIC/AlCl3/toluene bath effectively improves the brightness of the electrodeposited Al surfaces, a systematic series of molecules as additives were studied, and the results obtained for each molecule were compared carefully to determine the relationship between the brightness of the prepared Al surface and the molecular structure of the additive. The effect of additives, such as 4-PCAH and its analogs, on the surface brightness, electrodeposition efficiency and chemical composition of prepared Al films was examined using SEM, visible light reflectance measurements and XPS. The decrease in the surface roughness of the Al films causes the high surface brightness. The strong relationship (Fig. 1) between the high brightness and molecular structure of the additives included in the bath was elucidated via a systematic study of various additives. 4-PCAH achieved the highest surface brightness of the electrodeposited Al films prepared with various additives used in this study. [1] X. Fang, K. Uehara, S. Kaneko, S. Sato, T. Tanabe, T. Gunji, F. Matsumoto, Electrochemistry 84 (2016) 17-24. Figure 1. (A)Micrographs of the Al film surfaces obtained by the electrodeposition of Al from EMIC/AlCl3/toluene/4-PCAH baths, (B) Summary of the relationship between the reflectance of the prepared Al films at a wavelength of 450 nm and the molecular structure of the additive. Preparation conditions of the Al film: deposition time 2 h, constant current density 8 mAcm-2; bath composition: EMIC:AlCl3= 33.3 : 66.7 (mol%), toluene concentration: 9.25 M, additive concentration: 1.8 mM. Figure 1

Lithium-ion batteries (LIBs) have become the state-of-the-art power source for portable appliances, such as notebook computers, cellular phones, and digital cameras, and a prime candidate for hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and electric vehicles (EVs) because of their high energy density, high power density, superior cyclability and safety. The development of a higher capacity cathode material in particular is a matter of great urgency for the automobile industry because the currently attainable capacity of commercially available cathode materials for Li-ion batteries, such as LiCoO2 and LiMn2O4, is much lower than that of anode materials, which limits the expansion of LIB usage. A great deal attention has recently been focused on the Li-rich solid-solution layered cathode material Li2MnO3-LiMO2 (M = Co, Ni, etc.), which exhibits a discharge capacity of more than 200 mAhg-1 when operated above 4.6 V. The structural compatibility between Li2MnO3, which is electrochemically inactive and has a large theoretical capacity, and LiMO2, which is electrochemically active but has lower capacity, allows for the structural integration of these components at the atomic level. As a result, the electrochemically inactive Li2MnO3 can participate in the charge/discharge process after activation with oxygen release from the lattice during the charging process, while the capacity of LiMO2 can be improved by the stabilization of the layered LiMO2 structure by the Li2MnO3 component when more than 50% of the Li+ ions are deintercalated. In this study, the performance of the cathode material was investigated in detail by varying the charge/discharge voltage limits, cycle numbers, and current densities during pre-treatment [1] to reduce the duration of the pre-cycling process. In addition, search of composition of Li2MnO3-LiMO2 (M = Co, Ni, etc.) which exhibits high capacity and its duration and do not exhibit the decrease in the average discharge voltage with charge/discharge cycles was done. Specifically, the examined cathode material is considered to be solid-solution of Li2MnO3, LiCo1/3Ni1/3Mn1/3O2 and LiNi0.5Mn0.5O2. The relationship between the percentage of Li2MnO3, LiCo1/3Ni1/3Mn1/3O2 and LiNi0.5Mn0.5O2 in the solid-solution cathode material and the cathode performance mentioned above was examined with the half coin cells that were fabricated with the cathode and Li metal anode.

Recently, a new approach that avoids the problems inherent in disordered alloy catalysts has been proposed for highly active electrocatalysts for fuel cell applications [1]. In contrast with disordered alloys, intermetallic compounds with definite compositions and structures, such as PtPb and PtBi, exhibit excellent electrocatalytic performance towards FA oxidation in acidic solutions in terms of onset potential and current density [2]. Abruña et al. have examined the FA, MeOH, and EtOH oxidation activities with a wide range of intermetallic compounds (PtPb, PtBi, and Pt3Ti) in acidic media and found that the intermetallic compounds exhibit enhanced catalytic activity when compared with pure Pt [3]. In our previous study, we reported that PtPb and PtBi ordered intermetallic compounds exhibited higher electrocatalytic activity towards MeOH and EtOH oxidation in alkaline aqueous solutions than Pt, Pt-Ru alloy, and other Pt-based ordered intermetallic compounds [4]. In this paper, we report on the enhancement of the electrocatalytic activity of PtPb ordered intermetallic compounds towards MeOH and EtOH oxidation in alkaline aqueous solutions. To achieve this, carbon black (CB)-supported Pt3Pb(core)-PtPb(shell) intermetallic NPs (Pt3Pb-PtPb NPs/CB) were synthesized via a method (hereafter referred to as the “converting reaction method”) in which the CB-supported Pt NPs react with a Pb precursor in the presence of a reducing agent under microwave irradiation. In the converting reaction method, the Pb atoms were only observed in the PtPb NPs and not on the CB surfaces. In other words, Pb NPs were not formed on CB in the reaction with microwaves, indicating the selective reaction of Pb atoms with Pt NPs on the CB surfaces, as previously reported by Bauer and our group [5]. By controlling the amount of Pb atoms, the core-shell structure with Pt3Pb and PtPb intermetallic phases can be formed in a NP. The activities of Pt3Pb-PtPb NPs/CB were compared with those of the reference samples consisting of pure PtPb NPs/CB and Pt3Pb NPs/CB, which were prepared on the CB through the co-reduction reaction of the Pt and Pb precursors in the presence of a reducing agent and CB (hereafter referred to as the “co-reduction reaction method”). As mentioned above, previously, we have reported that PtPb and PtBi ordered intermetallic phases are the most promising electrocatalysts for MeOH and EtOH oxidations via the exhaustive screening of the ordered intermetallic phases for alkaline MeOH and EtOH oxidations [4]. In this research, our current results obtained with Pt3Pb-PtPb NPs/CB were compared with that of works mentioned above. [1] E.D. Casado-Rivera, J. Volpe, L. Alden, C. Lind, C. Downie, T. Vázquez-Alvarez, A.C.D. Angelo, F.J. DiSalvo, H.D. Abruña, J. Am. Chem. Soc. 126 (2004) 4043-4049. [2] D. Volpe, E.D. Casado-Rivera, L. Alden, C. Lind, K. Hagerdon, C. Downie, C. Korzeniewski, F.J. DiSalvo, H.D. Abruña, J. Electrochem. Soc. 151 (2004) A971-A977 [3] F. Matsumoto, C. Roychowdhury, F.J. DiSalvo, H.D. Abruña, J. Electrochem. Soc. 155(2008) B148-B154. [4] F. Matsumoto, Electrochemistry 80 (2012) 132-138. [5] J.C. Bauer, X. Chen, Q. Liu, T.-H. Phan, R.E. Schaak, J. Mater. Chem. 18 (2008) 275-282.

Recently, water-soluble and aqueous polymers (water-based polymers) have attracted much attention as binders for lithium ion batteries (LIBs) because of the need for low-cost materials and environmentally compatible electrode fabrication processes. For example, N-methyl-2-pyrrolidone (NMP), which is listed as a carcinogenic chemical with reproductive toxicity is often used as a solvent to prepare a slurry (cathode material particle/conducting carbon additive/conventional polyvinylidene difluoride (PVdF) binder/ NMP solvent) employed in the fabrication process of electrode films on current collectors; this slurry should be recycled without releasing it to the atmospheric environment. Therefore, switching from a nonaqueous-based fabrication process to an aqueous-based process has been widely investigated. The hurdles in developing water-soluble and aqueous polymer binders for use in cathodes in LIBs are still high; improvements are necessary to increase the resistance to electrochemical oxidation and dissolution of metal oxide surfaces in water. In order to overcome these problems, a variety of polymer materials have been applied in the fabrication of cathodes with water-based slurries. In recent years, Li-rich solid-solution layered cathode materials comprising layered LiMO2 (M: transition metals) and Li2MnO3 have attracted much interest because some materials exhibit capacities as high as 250 mAh g-1 in the voltage range of 2.0 and 4.8 V. These materials are charged to above 4.5 V (vs. Li/Li+) to fully activate the Li2MnO3 component, and after activation, the cathodes are charged to 4.5 V to reach discharge capacities over 250 mAh g-1. To use these promising high-voltage and high-capacity cathodes in the next-generation Li-ion batteries prepared in environmentally compatible electrode fabrication processes with a water-based binder, water-based binders having high resistances to electrochemical oxidation during charging process should be developed. In this study, an aqueous hybrid polymer (TRD202A, JSR), which was composed of acrylic polymer and fluoropolymer, was selected as a binder for the Li-rich solid-solution layered cathode material Li[Ni0.18Li0.20Co0.03Mn0.58]O2. A cathode prepared with Li[Ni0.18Li0.20Co0.03Mn0.58]O2 particles, TRD202A binder, CMC and conductive carbon additive was tested and analyzed for charge/discharge capacity, cycle stability, rate performance, mechanical resistance, resistance of electrochemical oxidation, and changes of the surface composition and structure after water-treatment used for preparing water-based slurry. The water-based TRD202A cathode binder is a water-based emulsion and is designed with a unique hybrid polymer developed from acrylic polymer and fluoropolymer to satisfy both the requirements of high adhesion and chemical and electrochemical resistances. Wu and co-workers have already reported an application of the TRD202 binder in a Li-rich solid-solution cathode. They mentioned that the TRD202A binder can be used for high-voltage cathodes in the voltage range of 2.0-4.6 V [1], and its thermal stability is equivalent to that of PVdF. However, they have not examined the water-based binders for charge/discharge capacities, long cycle stability, rate performance, mechanical resistance, resistance of electrochemical oxidation, or changes of the surface composition and structure after water-treatment used for preparing the water-based slurry. We have examined in depth the above points with the Li-rich solid-solution cathode (3/5)Li2MnO3·(1/5)Li[Ni0.5Mn0.5]O2 ·(1/5)Li[Ni1/3Co1/3Mn1/3]O2. [1] Wu Q, Ha S, Prakash J, Dees DW, Lu W (2013) Electrochim. Acta 114:1-6

Water splitting using a particle photocatalyst with visible light has attracted interest, because this will realize efficient conversion of the solar energy to hydrogen fuels for sustainable energy managements. Many water-splitting photocatalysts, such as metal-doped oxides, metal-(oxy)nitrides, and metal-oxysulfides, exhibit water reduction and oxidation ability when absorbing visible light. However, in such water-splitting photocatalysts, solely doping and/or replacement of foreign element at host material has been attempted to prepare visible-light-driven photocatalysts. The doping and/or replacement induces defect sites and charge imbalance into photocatalyst, resulting in the formation of recombination centers between excited electron and holes, in return to create new valence state. Therefore, the development of new native visible-light-sensitive photocatalyst for water splitting without doping of foreign elements is a major challenge for photocatalyst research. Herein, we report that an undoped metal oxide, Sn3O4, can efficiently catalyze Hydrogen (H2)-evolution in the presence of a sacrifice agent and, furthermore, can split water to H2 and O2 under irradiation of visible light by two-step photoexcitation (Z-scheme) systems using Sn3O4 as H2-evolving photocatalyst, combined with an appropriate O2-evolving photocatalyst in the presence of iodate/iodide (IO3 −/I−) as an electron mediator. We prepared nanocrystals of Sn3O4 by hydrothermal synthesis using sodium citrate as a ligand [1]. The Sn3O4 significantly catalyzed hydrogen evolution in aqueous solution in the presence of sacrifice agent under irradiation of visible light (λ>420nm), even without Pt co-catalyst. Pt co-catalyst was critical for Sn3O4 material to exhibit higher photocatalytic activity, so far in this study. The apparent quantum yield was 0.2% for high purity Sn3O4 and 1.5% for Pt loaded-Sn3O4, competitive to that of visible-light-sensitive doped metal oxide and (oxy)nitrides photocatalyst. Simultaneous evolution of H2 and O2 was attempted by using Sn3O4 as H2-evolving photocatalyst, combined with an appropriate O2-evolving photocatalyst (BiVO4, WO3 etc.,). By employing the appropriate combination of Sn3O4 and the redox couple (IO3 −/I−), simultaneous evolution of H2 and O2 stably proceeded with higher rates. [1] M. Maidhily, T. Tanabe, et al., ACS Appl. Mater. Interfaces 2014, 6, 3790.

Alloy nanoparticles (NPs) loaded TiO2 photocatalysts have attracted considerable attention in recent years as a promoter of highly active photocatalysts under ultraviolet (UV) irradiation [1]. Many synthetic techniques have been utilized in preparation of binary alloy NPs loaded TiO2. However, control of deposition site for alloy NPs on TiO2 is one of a challenging theme in TiO2 study. Herein, we present that site-selective Pt-Pb NPs deposition on rutile TiO2 nanorod by successive reduction of metal ions, photo-reduction of Pt4+ and followed by microwave assisted polyol reduction of Pb2+ (2-step method). The Pt-Pb NPs were site-selectively deposited on the reduction site on (110) surface of the rutile TiO2 nanorod. The photocatalytic activity of rutile TiO2 was significantly enhanced after Pt-Pb NPs loading for oxidative decomposition of AcOH in aqueous phase as shown in following figure. The AcOH was completely oxide to CO2 and the CO2 evolution of the site-selectively Pt-Pb NPs deposited TiO2 was nearly six times higher than that of a bare rutile TiO2 and three times higher than randomly Pt-Pb NPs deposited TiO2. The well mating of the reduction reaction site on photocatalyst, TiO2, and deposition site for co-catalyst, Pt-Pb NPs, induces efficient electron injection from photocatalyst TiO2 to co-catalyst Pt-Pb NPs, promoting oxygen reduction reaction, reduction process of AcOH oxidative decomposition. The accelerated electron consumption in reduction process leads to smooth oxidative decomposition of AcOH at oxidation site. These findings suggest that the site-selective deposition of alloy NPs is a predominant way to bring out catalytic performance of co-catalyst alloy NPs on TiO2. [1] T. Gunji, A. J. Jeevagan, M. Hashimoto, T. Nozawa, T. Tanabe, S. Kaneko, M. Miyauchi, F. Matsumoto, Appl. Catal B 181 (2016) 475-480. Figure 1

PtPb ordered intermetallic nanoparticles (NPs) was deposited on titanium oxide (TiO2)/cup-stacked carbon nanotube (CSCNT) for improvement of the activity of the electrochemical oxygen reduction reaction (ORR). Employment of CSCNT as a support material caused high loading of PtPb NPs/TiO2. The PtPb NPs/TiO2/CSCNT which was prepared by the step-by-step preparation method; annealing under inert gas atmosphere with Ti-alkoxide for TiO2, photodeposition for Pt NPs and microwave synthesis to prepare ordered intermetallic PtPb NPs on TiO2 via the reaction of Pb2+ with Pt/TiO2, exhibited the enhancement of ORR electrocatalytic activity. Scheme 1 shows a schematic depiction of the step-by-step preparation method of PtPb NPs/TiO2/CSCNT by annealing under inert gas atmosphere with Ti-alkoxide for TiO2, photodeposition for Pt NPs and microwave synthesis to prepare ordered intermetallic PtPb NPs on TiO2 via the reaction of Pb2+ with Pt/TiO2. A commercially available CSCNT (100 nmf, Sankei Giken Kogyo Co., Ltd., Japan) was treated with an acidic mixture solution of H2SO4 (6 M) and HNO3 (6 M) at 90 °C for 6 h to introduce a carboxylic acid functional group on the surfaces and then washed with water, followed by drying overnight at 110 °C. A Ti precursor solution was prepared by dissolving Titanium (IV) isopropoxide (TTIP, 0.2 g) in iso-propanol (100 mL). Functionalized carbon was added to the solution under vigorous stirring. De-ionized water (1.0 mL) was used to accelerate the reaction of TTIP. After further stirring for 6h, the resulting mixture was collected and dried overnight under vacuum condition, followed by heat-treatment at 450 °C for 1 h under Ar atmosphere to yield CSCNT-supported TiO2 (TiO2/CSCNT). Pt NPs were photochemically deposited on TiO2/CSCNT to prepared Pt NPs/TiO2/CSCNT. The Pt NPs/TiO2/CSCNT (0.030 g) and Pb(CH3COO)2 ¥3H2O (0.022 mmol) were dissolved in 50 mL of ethylene glycol. The mixture was then sonicated in a bath-type ultrasonicator and treated in the flask with a reflux set for 1 min under 300-W microwave radiation. The mixture in the flask was cooled to room temperature with water. The mixture was again treated under microwave (focused microwave instrument, CEM) radiation of 300 W for 9 min. After the mixture cooled, the PtPb NPs/TiO2/CSCNT was collected via centrifugation, washed sequentially with methanol and dried under vacuum. Figure 1 shows linear-sweep ORR voltammograms for (a) PtPb NPs/TiO2/CSCNT and (b) Pt NPs/CB in O2-saturated 0.1 M HClO4 solution. Here, CB-supported Pt NPs (b) was used as a control. The ORR curve (a) obtained with PtPb NPs/TiO2/CSCNT shifts to the positive direction, owing to the interaction between PtPb NPs and TiO2when compared with one of Pt/CB (b). Scheme 1. Schematic representation of the step-by-step methode to prepare ordered intermetallic PtPb NPs/TiO2/CSCNT Figure 1. Linear sweep voltammograms (LSV) for ORR on (a) PtPb/TiO2/CSCNT and (b) Pt/CB in O2-saturated 0.1 M HClO4 aqueous solution at 10 mVs-1. Inset: a TEM image of PtPb/TiO2/CSCNT used to obtain the LSV. Figure 1

In this study, we will report that the effectiveness of 4-pyridinecarboxylic acid hydrazide (4-PCAH) to smooth the deposited Al surfaces were compared with 3-pyridinecarboxylic acid hydrazide (3-PCAH), 2-pyridinecarboxylic acid hydrazide (2-PCAH) and PH in the view point of brightness, surface roughness and the film thickness. The Al films prepared with ionic liquid containing 4-PCAH showed brighter surfaces in the film thickness from 20 to 100 micrometer although generally the increase in the thickness of the deposited films causes the increase in the surface roughness. Figure 1 shows photographs of Al film obtained by electrodeposition of Al from (A) EMIC/AlCl3/toluene/4-PCAH, (B) EMIC/AlCl3/toluene/3-PCAH, (C) EMIC/AlCl3/toluene/2-PCAH and (D) EMIC/AlCl3/toluene/PH baths. In the baths, a constant current of 8 mAcm-2 (A-D) was used for electrodeposition of Al. In order to recognize the difference in brightness of Al surfaces, the characters of “KU UNIV” were reflected in the Al film surface. Whether the characters that were reflected in the Al surfaces can be seen or not is an index of surface brightness, in other words, surface smoothness. The Al films obtained with the EMIC/AlCl3/toluene/4-PCAH bath exhibits the highest brightness among four brighteners used in this study although the brightness became degrade as the deposition time became longer (Fig. 1). On the other hand, the Al films obtained with EMIC/AlCl3/toluene/PH bath and the deposition times of 2 h barely reflect the characters on its surface. In the deposition time which is longer 2 h, dull characters can be barely seen in the partial area. PH has been reported as a representative brightener for Al electrodeposition as long as we know in several papers. 4-PCAH which was applied to Al deposition for the first time as brightener by us exhibits remarkable effect for improvement of brightness of Al surface when compared with that obtained with EMIC/AlCl3/toluene/3-PCAH, EMIC/AlCl3/toluene/2-PCAH and EMIC/AlCl3/toluene/PH bath. The electrodeposition of Al from EMIC/AlCl3/toluene/4-PCAH bath for 2 h with 4 and 12 mAcm-2, and from EMIC/AlCl3/toluene/PH bath with 4 mAcm-2 showed degradation of the brightness. Employment of current of 12 mAcm-2 in the EMIC/AlCl3/toluene/PH bath naturally leaded to the same brightness as the deposited Al films prepared with 8 mAcm-2 from the EMIC/AlCl3/toluene/PH bath (these results are not shown here). Figure 2 shows reflectance spectra of Al films deposition from AlCl3-EMIC-toluene-4-PCAH (b), AlCl3-EMIC-toluene-3-PCAH (c), AlCl3-EMIC-toluene-2-PCAH (d) and AlCl3-EMIC-toluene-PH (e). The spectrum (a) was obtained with a commercial Al foil (A1N80H-H18, Mitsubishi Aluminum, Japan). Preparation conditions of Al films are deposition time of 2 h and constant current of 8 mAcm-2. The Al film obtained with AlCl3-EMIC-toluene-4-PCAH (b) exhibits the reflectivity similar to one observed with the Al foil, followed by the Al film obtained with AlCl3-EMIC-toluene-PH (e) in the view point of the reflectivity. Although the brighteners of 4-PCAH, 3-PCAH and 2-PCAH are positional isomer, the difference in the reflectivity of the Al films obtained with 4-PCAH, 3-PCAH and 2-PCAH are interesting result, indicating the importance of adsorption of brightener to Al surfaces. Fig. 1 Micrographs of the Al film surfaces obtained on a Cu substrate by coulometeric electrodeposition from (a) AlCl3-EMIC-toluene-4-PCAH, (b) AlCl3-EMIC-toluene-4-PCAH, (c) AlCl3-EMIC-toluene-2-PCAH and (d) AlCl3-EMIC-toluene-PH baths. Deposition time: 2 h; constant current: 8 mAcm-2. Fig. 2 Reflectance spectra of Al films deposition from AlCl3-EMIC-toluene-4-PCAH (b), AlCl3-EMIC-toluene-3-PCAH (c), AlCl3-EMIC-toluene-2-PCAH (d) and AlCl3-EMIC-toluene-PH (e). The spectrum (a) was obtained with a commercial Al foil. Figure 1

Three different porous Au catalysts that exhibit high catalytic activity for CO oxidation were prepared by the leaching of Al from an intermetallic compound, Al2Au, with 10 wt. %-NaOH, HNO3, or HCl aqueous solutions. The catalysts were investigated using Brunauer-Emmett-Teller measurements, synchrotron X-ray powder diffraction, hard X-ray photoelectron spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy (TEM). Broad diffraction peaks generated during the leaching process correlated with high activity for all the porous Au catalysts. CO oxidation catalyzed by porous Au leached with NaOH and HNO3 is considered to be dominated by different mechanisms at low (320 K) and high (370 K) temperatures. Activity in the low-temperature region is mainly attributed to the perimeter interface between residual Al species (AlOx) and porous Au, whereas activity in the high-temperature region results from a high density of lattice defects such as twins and dislocations, which were evident from diffraction peak broadening and were observed with high-resolution TEM in the porous Au leached with NaOH. It is proposed that atoms located at lattice defects on the surfaces of porous Au are the active sites for catalytic reactions.

The optically pure sulfone 15, prepared by the tandem asymmetric epoxidation and 1,2-rearrangement of the cyclopropylideneethanol 11 as a key step, was converted into the olefinic cyclobutanone 20 which was then transformed into the ketonic lactone 22 via the olefinic lactone 21. This constitutes the formal total synthesis of (−)-mesembrine (1).

The optically pure sulfone 15, prepared by the tandem asymmetric epoxidation and 1,2-rearrangement of the cyclopropylideneethanol 11 as a key step, was converted into the olefinic cyclobutanone 20 which was then transformed into the ketonic lactone 22 via the olefinic lactone 21. This constitutes the formal total synthesis of (−)-mesembrine (1).

In recent years, photocatalysis semiconductor, such as TiO2, WO3, are focused as environment remediation, H2 evolution, water splitting and CO2 reduction. Photocatalysts that respond in the visible light irradiation are very useful because they decompose harmful organic compounds such as acetic acid and formaldehyde in a room light or sunlight. Specifically, WO3 is attracting increasing interest because of visible light-responsive and are deeper valence band of hole. However, WO3 by itself cannot be used as a photocatalyst. The conduction band level of WO3 (+0.5 V vs. NHE) is slightly negative compared with the potential for the multi-electron reduction of oxygen (O2/H2O2 = 0.68 V vs. NHE). Therefore in order to use WO3 as a photocatalyst to decompose organic compounds, WO3 photocatalyst required a co-catalyst to facilitate oxygen reduction reaction on photocatalyst. Abe and co-workers reported that 1 wt. % Pt-loading WO3 (Pt NPs/WO3) effectively decomposed organic compound under visible and ultraviolet light in oxygen-rich atmosphere and its apparent quantum efficiency (QE) is ca 10%.1 This result was indicating that photocatalytic activity had been realized multi-electron reactions on Pt NPs that Pt as co-catalyst was facilitating oxygen reduction reaction on WO3. On the other hand, we previously reported that ordered interemetallic PtPb NPs efficiently electrocatalyzed oxidation of formic acid, methanol and ethanol.2 In our recent study, ordered intermetallic PtPb NPs on TiO2 was electrochemically accelerated the oxygen reduction reaction (ORR) in acidic media.3 In addition, We reported that H2PtCl6∙6H2O and Pb(CH3COO)2 were co-reduced using sodium borohydride to precipitate PtPb NPs (average particles size: 9.5 nm) over WO3 support (PtPb NPs/WO3). PtPb NPs/WO3 showed a substantial photocatalytic activity towards decomposition of acetic acid in aqueous solution.4 However, photocatalytic activity had not been enough because particle size was not controlled in this method, and detail of reaction mechanism was undisclosed. Here in, in order to increase photocatalytic activity towards decomposition of various organic compounds, we report intermetallic PtPb NPs as co-catalyst ofhotocatalysis. PtPb/WO3 has been synthesized via photodeposition and polyol method to control the particle size. The product was compared to the pure WO3 and Pt NPs/WO3towards decomposition of various organic compounds. In addition, we considerd the effectiveness of co-catalysts during decomposition of organic compounds. (1) R. Abe, H. Takami,N. Murakami and B. Ohtani, J. Am. Chem. Soc., 130, 7780-7781(2008). (2) T. Gunji and F. Matsumoto, et al, J. Power Sources, 273, 990-998 (2015) . (3) T. Gunji, G. Saravanan, T. Tanabe, T. Tsuda, M. Miyauchi, G. Kobayashi, H. Abe and F. Matsumoto, Catal. Sci. Technol., 4, 1436-1445 (2014). (4) Takao Gunji, Takashi Tsuda, Arockiam John Jeevagan, Masanari Hashimoto, Toyokazu Tanabe, Shingo Kaneko, Masahiro Miyauchi Govindachetty Saravanan, Hideki Abe and Futoshi Matsumoto, Catalysis Communications, 56, 96-100 (2014).

We are developing the micro-machine moving by converting chemical energy to mechanical energy to apply the micro-machine to drug delivery system. Our micro-machines were fabricated with two steps. In the first step, Au metal was electrochemically deposited on a Ag wire, following by the chemical dissolution of the Ag wire in strong acidic solution. In second step, inner walls of the cylinder of Au metal obtained with the dissolution process were used for fixing the glucose oxidase and catalase, that work in pair to convert chemical energy of glucose to mechanical energy of O2 gas formation, by adsorbing them with layer-by-layer method using polymer material (Fig. 1). The O2 gas formation becomes driving force of the micro-machine. We made two type of micro-machine with metal and polymer cylinders (Fig. 2). The time courses of metal cylinder type of micro-machine were monitored for 1 min (Fig. 3). When the enzyme of catalase was fixed on the inner wall of the metal cylinder, the micro-machines moved actively by the formation of O2 bubbles with oxidation of H2O2 on catalase. In the solution in the absence of H2O2, the micro-machine did not move except for slight movement due to natural convection of the solution. In order to remove the bubbles of O2 from the inner wall of the metal cylinder and to increase the moving rate of the micro-machine, a surfactant of TritonX-100 was added to the test solution where the micro-machines are moving. In addition, the micro-machine moved to the source of H2O2 (Fig. 4(a)), that is the micro-machine go up the gradient of H2O2 concentration. In the photographs of Fig.4, the injection points of H2O2 were located in the left side of the photographs. On the other hand, the micro-machine which was not modified with catalase did not move(b). Therefore, the moving direction of the micro-machines that we designed can be controlled by the gradient of chemical materials that produce the O2 bubbles by converting chemical energy to mechanical energy. Figure 1

1. Introduction Recently, interest in direct fuel cells (DFCs) has increased in the field of polymer electrolyte membrane (PEM) fuel cells in which small organic molecule (SOM) liquid fuels, such as methanol (MeOH), ethanol (EtOH), and formic acid (FA), were used as fuels.1 Ethanol is a particularly attractive fuel because it has a lower toxicity, it is biogenerated, and it does not release carbon that was previously sequestered underground as coal, petroleum, or natural gas into the atmosphere.2 However, the full potential of DFCs has not been realised due to the slow kinetics in the anode reactions.3 Literature reports have described much faster oxidation kinetics for organic fuels in alkaline media than in acidic media.4 One of the research and development challenges for alkaline-type polymer electrolyte fuel cells (PEFCs) using SOMs is the design of better alternatives to the Pt, Pd, and Pt-Ru alloys currently used as the anode catalysts.5 To improve the electrocatalytic activity, Pt- and Pd-based alloy electrocatalysts have been investigated in alkaline media.6 Although the aforementioned alloys are promising materials, problems are associated with the use of disordered alloys (and alloys in general) as catalysts for fuel cell applications, including the low utilisation of the surface for electrocatalysis, the surface segregation of metal atoms, and the partial poisoning by CO due to insufficient quantities of the bimetallic elements on the surface. A new approach that prevents the problems inherent in disordered alloy catalysts has been proposed for highly active electrocatalysts for fuel cell applications.7 In contrast with a disordered alloy, intermetallic compounds with definite compositions and structures, such as PtPb and PtBi, exhibit excellent electrocatalytic performance for oxidising FA in acidic solutions in their onset potential for oxidation and current density.8,9 Abruña and co-workers have examined the FA, MeOH and EtOH oxidation activities for a wide range of intermetallic compounds in acidic media and found a significant number of the compounds, such as PtPb, PtBi and Pt3Ti, exhibit enhanced catalytic activities compared with pure Pt.8, 9 Our previous study indicated that the PtPb and PtBi ordered intermetallic compounds exhibited higher electrocatalytic activity for MeOH and EtOH oxidation in alkaline aqueous solutions than other Pt, Pt-Ru alloy and Pt-based ordered intermetallic compounds.10 In this paper, to enhance the electrocatalytic activity of PtPb ordered intermetallic compounds toward MeOH and EtOH in alkaline aqueous solutions, carbon black (CB)-supported Pt3Pb-PtPb intermetallic compound core-shell NPs were prepared via a two-step synthesis in which Pt3Pb-PtPb intermetallic compound core-shell NPs were formed on the CB through the reaction of the CB-supported Pt NPs and a Pb precursor in the presence of a reducing agent under microwave irradiation (Fig.1). The possibility of developing high-performance DFCs using Pt3Pb-PtPb intermetallic compound core-shell NPs as anode catalysts for alkaline EtOH oxidation is demonstrated. 2 . Results and Discussion We have successfully synthesised Pt3Pb-PtPb intermetallic compound core-shell NPs through a two-step synthesis in ethylene glycol under microwave irradiation. The pXRD, HX-PES and TEM/STEM characterisations demonstrated that pure PtPb NPs and Pt3Pb-PtPb intermetallic compound core-shell NPs could be prepared using one- and two-step syntheses, respectively, without requiring annealing. The Pt3Pb-PtPb intermetallic compound core-shell NPs exhibited higher catalytic activity for ethanol oxidation in alkaline aqueous solutions, enhanced tolerance for CO-poisoning and improved stability compared with commercial Pt NPs or pure PtPb NPs. 3 . References 1. N.W. Deluca and Y.A. Elabd, J. Polym. Sci., Part B: Polym Phys., 2006, 44, 2201. 2. E. Antolini, J. Power Sources, 2007, 170, 1. 3. A.V. Tripkoviæ, K.D. Popoviæ, B.N. Grgur, B. Blizanac, P.N. Ross, and N.M. Markoviæ, Electrochim. Acta, 2002, 47, 3707. 4. J.S. Spendelow and A. Wieckowski, Phys. Chem. Chem. Phys., 2007, 9, 2654. 5. A. Verma and S. Basu, J. Power Sources, 2005, 145, 282. 6. M. Nie, H. Tang, Z. Wei, S.P. Jiang, and P.K. Shen, Electrochem. Commun., 2007, 9, 2375. 7. E.D. Casado-Rivera, J. Volpe, L. Alden, C. Lind, C. Downie, T. Vázquez-Alvarez, A.C.D. Angelo, F.J. DiSalvo and H.D. Abruña, J. Am. Chem. Soc., 2004, 126, 4043. 8. D. Volpe, E. Casado-Rivera, L. Alden, C. Lind, K. Hagerdon, C. Downie, C. Korzeniewski, F.J. DiSalvo and H.D. Abruña, J. Electrochem. Soc.,2004, 151, A971. 9. F. Matsumoto, C. Roychowdhury, F.J. DiSalvo and H.D. Abruña, J. Electrochem. Soc., 2008, 155, B148. 10. F. Matsumoto, Electrochemistry, 2012, 80, 132.

Stable and long-term electrocatalytic performance towards cathodic oxygen reduction reaction (ORR) was achieved by impregnation of Pt-based nanoparticles (NPs) on anatase titania (TiO2) support. For example, organometallic precursors PtCODCl2 and C10H14CuO4 and TiO2 or carbon black (CB) supports were co-reduced using lithium triethylborohydride to achieve intermetallic phase between Pt and Cu on TiO2(or CB) under ambient temperature. Finely dispersed PtCu NPs with an average particle size of 3 nm were achieved through wet-chemical synthetic route. Potential cycle with PtCu/CB in 0.1 M HClO4 aqueous solution between 0.4-1.1 V (vs. RHE) accelerates ORR (Fig. 1) because of the formation of dealloyed surface of PtCu NPs caused by dissolution of Cu from the surface of PtCu NPs. The dealloyed PtCu/CB showed the highest electrocatalytic activity both in terms of onset potential as well as cathodic current density compared to Pt/CB as well as PtPb/CB and PtNi/CB towards ORR (Fig. 2). The onset potential of PtCu/TiO2 is shifted to higher electric potential by 180 mV compared to Pt/CB (Fig. 3).

The long-term, stable, and improved electrocatalytic performance towards the oxygen reduction reaction (ORR) has been achieved by anatase-type titania (TiO2)-supported PtPb nanoparticles (NPs). Organometallic precursors, H2PtCl6·6H2O and Pb(CH3COO)2 were co-reduced using sodium borohydride at ambient temperature to precipitate the PtPb NPs (NiAs-type structure, P63/mmc, a = 0.4259 nm; c = 0.5267 nm, average particle size: 3 nm) over the TiO2 support (PtPb/TiO2). PtPb/TiO2 showed substantial electrocatalytic activity towards ORR both in terms of the onset potential and the mass activity compared to TiO2-supported Pt NPs (Pt/TiO2). The onset potential of PtPb/TiO2 was shifted to a higher electric potential by 180 mV compared to Pt/TiO2. Also, PtPb/TiO2 showed a seven-times higher ORR mass activity than Pt/TiO2. Neither the onset potential nor the mass activity of PtPb/TiO2 was altered after ORR cycles, whereas those of commercially available Vulcan carbon-supported Pt NPs (Pt/VC; Pt loading: 20 wt%) were largely altered. The PtPb NPs were not agglomerated over the TiO2 support even after repeated cycles under the electric potential condition, as the result of the strong interactions between the PtPb NPs and the TiO2 support, but the Pt NPs were significantly agglomerated over the TiO2- and the Vulcan carbon-supports due to the weak interactions between the Pt NPs and the supports. PtPb/TiO2 can be a practical cathode material for direct fuel cells in terms of its long-term stability and enhanced catalytic performance.

Gold nanoparticle (NP) photosensitization over semiconductors with a large band gap has emerged as a promising strategy for developing visible-light responsive photocatalytic materials. However, its application in harsh photocatalytic oxidation still remains a significant challenge. Furthermore, energetic charge carriers created in Au interband transitions under visible light are frequently ignored in this field. In the current work, for the first time, a remarkable visible-light photocatalytic water oxidation activity (14.9 μmol h−1: 0.2 g catalyst, 5 mmol AgNO3), even slightly higher than that of commercial WO3, was achieved over Au photosensitized SrTiO3 (1.1 wt%). In an elaborate study, electron transfer from gold to SrTiO3 was confirmed by STEM-EDS characterization on selective Ag deposition over SrTiO3. A combined investigation of apparent quantum efficiency results, theoretical simulation study on Au NPs optical excitation and relative band position analysis in Au/SrTiO3 reveals that these hot electrons transferred from gold to SrTiO3 mainly come from Au interband transitions other than plasmon resonance, while leaving holes on Au with enough oxidative potentials are responsible for water oxidation. The capability of involving Au interband transition in photosensitization for visible light water oxidation opens up new opportunities in designing and preparing visible-light responsive photocatalysts.

The purities of tin metals are determined directly by precise coulometric titration. The sample is dissolved with hydrochloric acid in a nitrogen atmosphere. The solution is then introduced into a hot antimony column. The reduced tin(II) ions are titrated with electrolytically-generated iodine. The titration is accomplished in a special cell by the use of which any disturbance of atmospheric oxygen is avoided. The titration efficiency under these acidic media was decreased when the current density was increased more than several mA/cm2. The results obtained by two different analysts for the sample of the pure tin metal (5-nine) were 99.996 and 99.991%. The standard deviations of the results were 0.025 and 0.016% respectively. The tin in the other tin metals and in Zircaloy samples was determined satisfactorily without the use of any experimental factor.