Phosphorus-doped hexagonal tubular carbon nitride (P-TCN) with the layered stacking structure was obtained from a hexagonal rod-like single crystal supramolecular precursor (monoclinic, C2/m). The production process of P-TCN involves two steps: 1) the precursor was prepared by self-assembly of melamine with cyanuric acid from in situ hydrolysis of melamine under phosphorous acid-assisted hydrothermal conditions; 2) the pyrolysis was initiated at the center of precursor under heating, thus giving the hexagonal P-TCN. The tubular structure favors the enhancement of light scattering and active sites. Meanwhile, the introduction of phosphorus leads to a narrow band gap and increased electric conductivity. Thus, the P-TCN exhibited a high hydrogen evolution rate of 67 μmol h(-1) (0.1 g catalyst, λ >420 nm) in the presence of sacrificial agents, and an apparent quantum efficiency of 5.68 % at 420 nm, which is better than most of bulk g-C3 N4 reported.

We present a simple and feasible strategy to synthesize the novel anatase TiO2/graphene composites with exposed TiO2 {001} high-energy facets by the hydrofluoric acid and methanol joint assisted solvothermal reactions. During the synthesis process, graphene was uniformly covered with a large number of anatase TiO2 nanoparticles (20–25 nm), exposing the {001} facets. The X-ray photoelectron spectroscopy and X-ray absorption measurements show the presence of electron transfer between TiO2 and graphene. Furthermore, transient photovoltage spectra of the composite also exhibits prolonged mean lifetime of electron–hole pairs compared with pure TiO2. The electron transfer between Ti and C will greatly retard the recombination of photoinduced charge carriers and prolong electron lifetime, which contribute to the enhancement of photocatalytic performance. During the photocatalysis measurement, the TiO2/graphene composites have high photocatalytic activity compared with the P25 under UV light, likely due to the effective separation of photoinduced charge and exposure of high reactive {001} facets.

A series of trans-(FcC(2n))Ru(2)(Y-DMBA)(4)(C(2m)Fc) with n, m = 1 and 2 and Y-DMBA as N,N'-dimethylbenzamidinate or N,N'-dimethyl-(3-methoxy)benzamidinate have been synthesized and characterized. The intramolecular Fc...Fc distances, established through single-crystal X-ray diffraction studies, range from 11.6 to 16.6 A. Results from both voltammetric and spectroelectrochemical studies indicate that the (-C(2n))Ru(2)(Y-DMBA)(4)(C(2m-) fragments are among the most efficient mediators of intramolecular hole transfer. Density-functional calculations offer both the insight on the ground-state electronic properties and unambiguous assignment for the observed electronic absorptions.