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The fabrication of printed electronic circuits using solution-based electroconductive materials at low temperature is essential for the realization of modern printed electronics including transistors, photovoltaic cells, and light-emitting devices. Despite the progress in the field of semiconductor solution materials, reliable electrodes are always fabricated by a vacuum deposition process resulting in only partially solution-processed devices. In this paper, we show that planar phthalocyanine-conjugated Au nanoparticles (NPs) significantly improve the interparticle-carrier-transport properties. The deposition of a solution of the Au NPs under ambient conditions results in an electroconductive metallic thin film without further post-treatment. Maximum conductivity reaches >6600 S cm ¹1 and the conductivity remains unchanged for at least 1 year under ambient conditions. The all-solution-processed organic field-effect transistor (OFET) fabricated under ambient conditions exhibits mobility values as high as 2 cm 2 V ¹1 s ¹1, the value of which is comparable to OFET devices having vacuum-deposited Au electrodes.Electrodes are necessary in all types of electric devices such as transistors, photovoltaic cells, and light-emitting devices. These devices are commonly fabricated by employing expensive vacuum deposition processes. A promising alternative that is cheaper and faster for fabricating devices is wet printing using material from specially designed solutions.1 Many examples of solution processes for transistors, 210 photovoltaic cells, 11 and light-emitting devices 12 have been reported. However, in order to achieve high efficiency and reliable devices, vacuum-processed metals and conductive metal oxide electrodes must be used, thereby producing only partially solution-processed devices. To realize the fabrication of allsolution-processed devices, electrodes must be fabricated at relatively low temperatures from a solution, and the resultant electrode must fulfill three requirements: they must have (1) good contacts, i.e., low resistance at the semiconductor electrode interface, (2) high electroconductivity, and (3) high oxidation stability. In this study, we report that the Au nanoparticles (NPs) possessing orbital hybridization between the Au core and relatively large aromatic molecules meet these three requirements, and consequently, produce reliable electrodes that are comparable to vacuum-deposited Au electrodes.For the fabrication of NP-based electrodes under ambient conditions, surface ligands of inorganic NPs must meet two requirements: they must (1) adhere firmly to the NP surface for colloidal stabilization and (2) provide stable and facile carrier transport between NPs. We found that orbital hybridization between ³ orbitals of aromatic molecules and inorganic orbitals of the Au NPs improves the interparticle-carrier transport. The molecular orbital structure of aromatic compounds is altered when the ³-conjugated plane of aromatic compounds closely bonds while parallel to the metal surface, 1315 and thi...

Direct catalytic hydrothermal conversion of cellulose to C 3 + C 4 hydrocarbons at a low temperature (443 K) over a Pt/zeolite catalyst without hydrogen or other expensive reagents was investigated. Pt supported on NH 4 + -form ultra-stable Y-type (NH 4 -USY) zeolite catalyst, which showed the highest activity among the tested Pt/zeolite catalysts, has appropriate acidity and a suitable active Pt site. The C 3 + C 4 hydrocarbon yield reached 14.5 C-% during the reaction over the Pt/NH 4 -USY catalyst at 443 K after 72 h of the reaction. Results showed that the acid strength of the zeolite support was an important factor affecting the cellulose decomposition activity. Because of their structural sensitivity, Pt/zeolite catalysts with Pt particles larger than 5 nm, including Pt/NH 4 -USY catalyst, showed higher TOF values than catalysts with Pt particles smaller than 5 nm.

The cover picture shows that important petrochemical feedstocks of C3+C4 hydrocarbons are directly produced from the biomass‐derived cellulose without external hydrogen or other expensive reagents. This direct catalytic conversion selectively proceeded, even at low temperature, by the bifunctional catalysis of Pt supported on zeolite catalyst. Acid site on zeolite catalyzes cellulose degradation to liquiform products, and Pt site does its conversion to hydrocarbons. Pt/zeolite catalysts with Pt particles larger than 5 nm showed a high catalytic activity by virtue of the existence of highly active Pt sites (i.e. high index {311} and {331} facets). More information can be found in the Full Paper by Shuhei Ogo et al. (DOI: 10.1002/slct.201701035). (Design: Shuhei Ogo).