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Abstract We implanted polyimide (PI) ion-track membranes with 100 keV Ar+ to prepare a cathode for the galvanic deposition of platinum (Pt) nanocones. The surface layer of the irradiated PI films was carbonized to produce a graphitic structure at a fluence of 7.6 × 1016 ions/cm2. The carbonized surface exhibited an electric conductivity and electrochemical stability, which could be sufficient for use as a cathode. Pt nanocones were electrodeposited into the pores of the PI ion-track membrane after the implantation under the same conditions. This indicated that the Ar+ irradiation resulted in the preparation of a conductive layer on the total surface area of the ion-track membrane including the innermost regions of the pores. Highlights • Polyimide ion-track membranes were irradiated with 100 keV argon ions (Ar+). • The surface of the membranes became conductive due to carbonization. • The Ar+-irradiated surface was employed as an electrode for electrodeposition. • Platinum nanocones were electrodeposited into the pores of the membrane. [ABSTRACT FROM AUTHOR]

Abstract A glassy carbon (GC) substrate was irradiated with 380 keV argon ions (Ar+), and platinum nanoparticles (Pt NPs) were then deposited on it by a radio-frequency magnetron sputtering method. The interfacial effect of the Ar+-induced defects in the GC substrate on the size and electronic structure of the Pt NPs was investigated. The irradiation defects in the carbon support promoted the growth of the Pt NPs on the substrate, leading to a larger NP size. Density functional theory calculations revealed that the lattice vacancies in the graphitic structure lowered the position of the Pt d-band center via the interfacial charge transfer. This down-shift in the d-band center would be a reason for the higher catalytic activity, which was reported in our previous research. Highlights • The Pt nanoparticles were deposited on a 380 keV Ar+-irradiated carbon support. • The particle sizes on the irradiated and non-irradiated support were investigated. • A Pt electronic structure was modified by the irradiation defects of the carbon support. • We discussed how the Pt size and electronic structure affected the catalytic activity. [ABSTRACT FROM AUTHOR]

Abstract The chemical state and local structure of 2.6-nm-sized platinum (Pt) nanoparticles on an ion-irradiated glassy carbon (GC) substrate were investigated by X-ray absorption fine structure measurements. The partial oxidation of the Pt nanoparticles was confirmed by the peak intensity in the near-edge region of the absorption spectrum. The analysis of the extended region revealed a higher coordination number and shorter bond length of Pt–Pt compared to those of the Pt nanoparticles on the non-ion-irradiated GC. Thus, Pt nanoparticles on the ion-irradiated GC substrate were found to hold a rigid metallic coordination during the oxidation. Highlights • Pt nanoparticles were deposited on a 380 keV Ar+-irradiated carbon support. • The partial oxidation of Pt was confirmed by XANES measurements. • Pt on the irradiated support held a rigid metallic coordination during oxidation. [ABSTRACT FROM AUTHOR]

Novel xanthene dyes having thienyl and thieno[3,2- b ]thienyl rings as auxochrome have been synthesized. The UV–vis absorption maximum in dichloromethane was in the order of the auxochrome: NEt 2 (Rhodamine B, 558 nm) < 2-thienyl (569 nm) < 5-thieno[3,2- b ]thienyl (608 nm). These new xanthene dyes colored only in non-hydrogen-bond accepting solvents such as chloroform and dichloromethane. The lactone precursors of the thienyl and thieno[3,2- b ]thienyl derivatives colored by adding strong acids whose p K a value is lower than −2.2 and 0.23, respectively, whereas that of rhodamine B colored by adding weak acids whose p K a value is lower than 4.7. These results originate from less stability of colored cationic dyes by the heteroaromatics than by the diethylamino auxochrome. [ABSTRACT FROM AUTHOR]