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After chirality‐specified growth of single‐walled carbon nanotubes (SWCNTs) was realized by tungsten‐based intermetallic compound catalysts, here we developed a different kind of intermetallic compound, cobalt disilicide (CoSi2), as catalysts to selective grow carbon nanotubes by chemical vapor deposition (CVD). By using methane as carbon source, we obtained (11, 7) tubes with the selectivity of ∼24% and semiconducting SWCNTs (s‐SWCNTs) with the purity of ∼93% simultaneously. Because of the sensitivity of CoSi2 toward the oxygen‐containing environment at high temperatures, ethanol is not a good carbon feedstock. Our results not only expand the chirality library and catalyst database in the chirality‐selective synthesis of SWCNTs, but also further demonstrate the feasibility of intermetallic compound catalysts. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials, such as fullerene, carbon nanotubes (CNTs), and graphene, are competitive candidate materials for photovoltaic (PV) applications. Fullerenes and their derivatives have tunable energy levels and high mobilities, which makes them the most popular electron acceptors for organic solar cells (OSCs). Tailoring the energy levels and packing behaviors of fullerenes by well-designed chemical modification is essential to improve the performance of fullerene-based electron acceptors. Semiconducting single-walled CNTs can play similar roles in OSCs. Owing to the extremely high mobilities, CNTs and graphene are incorporated as charge transport materials. They are also promising candidates for transparent electrodes, especially in flexible PV devices. Besides OSCs, CNT and graphene films can form heterojunctions with inorganic semiconductors and CNTs themselves can also form bipolar diodes by using asymmetrical metallic contacts. Solar cells based on these kinds of junctions exhibit high efficiencies and can be multiplied to obtain higher voltages and currents. By further optimizing the molecular design and methods for preparation, handling and assembling of carbon nanomaterials, performance of the PV devices can be further improved. Then the real application of carbon nanomaterials in PV devices is expected. [ABSTRACT FROM AUTHOR]

Flexible supercapacitor with all components monolithically integrated into an on-chip paper substrate demonstrates excellent electrochemical and mechanical performance. Supercapacitors are drawn with a conductive ink of nitrogen-doped carbon nanotube and graphene ink, which has been prepared without assistance of surfactant. The engineering strategy is intrinsically scalable toward flexible paper devices. [Display omitted] • A surfactant-free ink of nitrogen-doped carbon nanotubes and graphene is prepared. • The electrodes are integrated onto a paper in mirror image. • The resultant supercapacitor presents a high volumetric capacitance of 0.45 F cm−3. • The strategy is intrinsically scalable toward flexible supercapacitors. We demonstrate a facile strategy to fabricate flexible paper-based supercapacitors, in which all the components are integrated onto a paper with poly (vinyl alcohol)/H 3 PO 4 as the gel electrolyte. The electrodes are drawn on both sides of the paper in a mirror image with a surfactant-free ink of nitrogen-doped carbon nanotubes and graphene. The resultant supercapacitors present a high volumetric capacitance of 0.45 F cm−3 and an energy density of 40.0 μWh cm−3. Moreover, this strategy is intrinsically scalable toward flexible energy devices while maintaining their electrochemical and mechanical performance. [ABSTRACT FROM AUTHOR]