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Graphitic carbon nitrides were employed to prepare the Ruthenium-based ammonia synthesis catalysts by thermal decomposition of Ru3(CO)12 under N2 or H2 atmosphere. Different pretreatment atmospheres significantly affected the interaction between Ru nanoparticles and the graphitic carbon nitride. The strong metal support interaction enhanced the electronic density transfer from rich-electron π-plane of the support to the Ru nanoparticles. And it further caused the upshift of d-band center of Ru nanoparticles. The upshift of d-band center improved the ability of surface to bond to N2, and consequently the ammonia synthesis activity was enhanced. Electron-rich and graphitic carbon nitride enhanced the electron density of Ru nanoparticles. And that caused the upshift of d-band center of Ru nanoparticles. This upshift of d-band center improved the ability of surface to bond to N2, and consequently the ammonia synthesis activity was enhanced.

A combined experimental and theoretical study was carried out to investigate the ambipolar charge transport properties of a series of N-heteropentacenes in organic field-effect transistors (OFETs). Introduction of nitrogen atoms in the core and halogen atoms around the periphery of the pentacene framework can efficiently tune the highest occupied molecular orbitals (HOMOs) of the N-heteropentacenes from −5.18 eV to −5.53 eV and the lowest unoccupied molecular orbitals (LUMOs) from −3.08 eV to −3.69 eV. By lowering their HOMO and LUMO energy levels with respect to the Fermi level of the gold electrode, the transistors of these molecules exhibited a transition from hole-dominant bipolar, to balanced ambipolar, and to electron-dominant bipolar transport characteristics. Meanwhile, with the lowering of the frontier molecular orbital energy levels, the transistors also exhibited a decrease of the electron threshold voltage and an increase of the hole threshold voltage. Charge carrier mobility calculations based on Marcus theory and first principle molecular dynamics were conducted to simulate the carrier transport dynamics. The comparison between experimental and theoretical results revealed that for the given device structure, the ratio of electron and hole mobilities of the ambipolar OFETs was strongly affected by the charge injection barrier. This result provides useful guidelines for future molecular design of ambipolar OFETs.

Two series of new oligothiophene-pentacene hybrid compounds were successfully synthesized and characterized, which consist of pentacene and anthradithiophene skeletons modified by different oligothienyl groups at 6,13 sites or 5,11 sites, respectively. Their optical, thermal, and electrochemical properties show regular variations with the length change of the side groups. These materials exhibit much higher solubility and significantly improved thermal and photooxidation stabilities compared with unmodified pentacene and anthradithiophene.

In the title compound, C30H38O4S2, the centroid of the benzene ring lies on a center of inversion. The thiophene ring is aligned at 49.8 (1)° with respect to the benzene ring. The alkyl chain adopts an extended zigzag conformation.