Nitrogen-doped one-dimensional (1D) macroporous carbonaceous nanotube arrays and their application in electrocatalytic oxygen reduction reactions

A nitrogen(N)-doped one-dimensional (1D) macroporous carbonaceous nanotube array was fabricated by using an anodic alumina oxide (AAO) template. The large diameter of the nanotubes (∼200 nm) could overcome the sluggish mass transfer phenomena in the common micro/mesoporous carbon-based electrodes. Combining the activation of the π electrons of the sp(2) carbon array by N-doping, the novel 1D macroporous carbonaceous nanotube array exhibited high performance for the oxygen reduction reaction (ORR).

Mesoporous carbon-TiO₂ beads with nanotextured surfaces as photoanodes in dye-sensitized solar cells

Mesoporous TiO2 and carbon-TiO2 beads with highly roughened surfaces at the nanoscale were prepared by using triblock copolymer P123 simultaneously as template and carbon source in combination with colloid self-assembly. In addition, their role as modifier of the photoanode in the efficiency enhancement of dye-sensitized solar cells is discussed. Hierarchically organized TiO2 networks can provide fast electron transport paths, and ordered mesopores can enhance light scattering as well as facilitate infiltration of the electrolyte. It was found that there is an optimum loading level of mesoporous TiO2 and carbon-TiO2 beads, that is, 1.0 and 0.5 wt%, with respect to the control P25 TiO2 nanoparticles, respectively, for maximizing the photovoltaic performance. An increase in the photovoltaic performance by up to 21.45% was achieved by incorporation of mesoporous carbon-TiO2 beads into the conventional photoanode of DSSCs owing to enhanced charge transport and collection effects.

Soft-template-carbonization route to highly textured mesoporous carbon–TiO2 inverse opals for efficient photocatalytic and photoelectrochemical applications

A significantly enhanced visible light photocatalytic activity was demonstrated for highly ordered mesoporous carbon–TiO₂ inverse opal nanostructures.