National Institute of Advanced Industrial Science and Technology

About: National Institute of Advanced Industrial Science and Technology is a government organization based out in Tsukuba, Ibaraki, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 22114 authors who have published 65856 publications receiving 1669827 citations. The organization is also known as: Sangyō Gijutsu Sōgō Kenkyū-sho.

Pd Nanocubes@ZIF‐8: Integration of Plasmon‐Driven Photothermal Conversion with a Metal–Organic Framework for Efficient and Selective Catalysis

Abstract: Composite nanomaterials usually possess synergetic properties resulting from the respective components and can be used for a wide range of applications. In this work, a Pd nanocubes@ZIF-8 composite material has been rationally fabricated by encapsulation of the Pd nanocubes in ZIF-8, a common metal-organic framework (MOF). This composite was used for the efficient and selective catalytic hydrogenation of olefins at room temperature under 1 atm H2 and light irradiation, and benefits from plasmonic photothermal effects of the Pd nanocube cores while the ZIF-8 shell plays multiple roles; it accelerates the reaction by H2 enrichment, acts as a "molecular sieve" for olefins with specific sizes, and stabilizes the Pd cores. Remarkably, the catalytic efficiency of a reaction under 60 mW cm(-2) full-spectrum or 100 mW cm(-2) visible-light irradiation at room temperature turned out to be comparable to that of a process driven by heating at 50 °C. Furthermore, the catalyst remained stable and could be easily recycled. To the best of our knowledge, this work represents the first combination of the photothermal effects of metal nanocrystals with the favorable properties of MOFs for efficient and selective catalysis.

Novel conjugated organic dyes for efficient dye-sensitized solar cells

Abstract: Novel conjugated organic dyes that have N,N-dimethylaniline (DMA) moieties as the electron donor and a cyanoacetic acid (CAA) moiety as the electron acceptor were developed for use in dye-sensitized nanocrystalline-TiO2 solar cells (DSSCs). We attained a maximum solar-energy-to-electricity conversion efficiency (η) of 6.8 % under AM 1.5 irradiation (100 mW cm–2) with a DSSC based on 2-cyano-7,7-bis(4-dimethylamino-phenyl)hepta-2,4,6-trienoic acid (NKX-2569): short-circuit photocurrent density (Jsc) = 12.9 mA cm–2, open-circuit voltage (Voc) = 0.71 V, and fill factor (ff) = 0.74. The high performance of the solar cells indicated that highly efficient electron injection from the excited dyes to the conduction band of TiO2 occurred. The experimental and calculated Fourier-transform infrared (FT-IR) absorption spectra clearly showed that these dyes were adsorbed on the TiO2 surface with the carboxylate coordination form. A molecular-orbital calculation indicated that the electron distribution moved from the DMA moiety to the CAA moiety by photoexcitation of the dye.

Electrochemical Performance of Nitrogen-Enriched Carbons in Aqueous and Non-Aqueous Supercapacitors

Abstract: Carbon materials with significant nitrogen contents were investigated as the electrode materials of supercapacitors. The preparation procedure involved the polymerization of melamine in the interlayer space of template fluorine mica and carbonization at 750, 850, and 1000 degrees C. Some samples were also stabilized prior to carbonization. We have shown previously that these carbons possess very interesting capacitive behavior in an acidic medium despite small surface areas. High capacitance values in H2SO4 were attributed to the pseudocapacitive interactions between the protons and nitrogen atoms. This paper further discusses the results obtained in a base and an aprotic electrolyte, KOH and TEABF(4)/PC, respectively. Electrochemical properties were evaluated with cycling voltammetry, a galvanostatic charge/discharge technique, and electrochemical impedance spectroscopy. High capacitance values were obtained in proton-free KOH, and the presence of pseudocapacitive interactions between the ions of the electrolyte and the nitrogen atoms of the carbon matrix is proposed. Compared to those in sulfuric acid, greater capacitances of nonstabilized samples were obtained in KOH, i.e., for the sample carbonized at 1000 degrees C, the capacitance was 84.61 F/g in KOH vs 47.92 F/g in H2SO4. On the other hand, less porous but more nitrogen-rich stabilized samples gave better performances in H2SO4, i.e., 62.24 F/g in H2SO4 compared to 49.86 F/g in KOH for the sample stabilized and carbonized at 1000 degrees C. The sample heat-treated at 750 degrees C with a surface area of ca. 400 m(2)/g performs similarly in both electrolytes, i.e., similar to 200 F/g. Significantly lower gravimetric capacitances were obtained in TEABF(4)/PC from the samples carbonized at 750 degrees C. On the other hand, the almost nonporous sample subjected to stabilization prior to carbonization at 1000 degrees C gave a capacitance of similar to 20 F/g. Hence, we suggest that the faradaic interactions between the carbon electrode material and the electrolyte, although much less significant than those in H2SO4 and KOH, play an important role in the nonaqueous electrolyte as well. Narrow micropores were detected by CO2 adsorption/desorption, and their importance to the interpretation of capacitive behavior is also discussed.

Layered lithium transition metal oxide cathodes towards high energy lithium-ion batteries

Abstract: Development and discovery of cathode materials with superior performance seem to be tremendous challenges for Li-ion battery scientists. Since the topotactic reaction was first demonstrated in the 1970s, layered Li transition metal oxides (LiMO2, M = Co, Ni, Mn) have been a shining star throughout the research and innovation in intercalation materials due to their appealing merits. Generally the basic LiMO2 with a single kind of transition metal ion suffers from safety concerns and structural instability and can not support high energy Li-ion batteries. Nowadays, Li-stoichiometric mixed metal oxides and Li-excess Mn-based oxides have been considered as the most promising families of cathode materials for large-scale Li-ion batteries with high energy density used for transportation. In the present paper, with the help of a phase diagram tetrahedron, we provide an overview of the major developments in the field of LiMO2 cathode materials. The changes in structure during Li extraction and the phase compatibility of Li mixed metal oxides are highlighted. The latest progress in the research of Li-excess Mn-based oxides is also included.