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Carbon nanotubes (CNTs) possess exceptional mechanical properties, surpassing stiffness and strength metrics of common materials such as steel alloys by 100 × at the nanoscale. However, when myriads of individual CNTs are bundled together into macroscopic ensembles like fibers or sheets, the result is a 100-fold drop in strength compared to its individual components. Here we present a general strategy aimed to close this gap in property scaling. By using vapor-phase polymerization of a crosslinkable polymer, we reinforced the weak interlinkages among individual CNTs within both yarns and sheets to promote a better transference of mechanical load across the structure. After the treatment, dry-spun, low-density 2.3 μm thin yarns increased their elastic moduli by at least 300%, and free-standing CNT sheets exhibited a 10 × boost. In-situ synchrotron small-angle X-ray scattering revealed that polymer-reinforced yarns undergo limited CNT bundle rearrangement when subjected to tensile loads compared to pristine yarns. This evidence supports the hypothesis that the polymer hinders CNTs slippage, the root cause of the poor scaling of mechanical properties in these materials. While we demonstrated this reinforcement method for CNT structures, it is not specific to CNTs and could be used in a wide variety of other hierarchical nanostructured ensembles.

We report two examples of initiated chemical vapor deposition (iCVD) polymers being developed for use in laser targets for high peak-power laser systems. First, we show that iCVD poly(divinylbenzene) is more photo-oxidatively stable than the plasma polymers currently used in laser targets. Thick layers (10–12 μm) of this highly crosslinked polymer can be deposited with near-zero intrinsic film stress. Second, we show that iCVD epoxy polymers can be crosslinked after deposition to form thin adhesive layers for assembling precision laser targets. The bondlines can be made as thin as ~ 1 μm, approximately a factor of 2 thinner than achievable using viscous resin-based adhesives. These bonds can withstand downstream coining and stamping processes.

Towards the goal of providing a continuous process for the solid-state fabrication of carbon nanotube sheets and yarns from carbon nanotube forests, we report the growth of yarn-spinnable and sheet-drawable carbon nanotube forests on highly flexible stainless steel sheets, instead of the conventionally used silicon wafers. Sheets and yarns were fabricated from the 16 cm maximum demonstrated forest width, from both sides of a stainless steel sheet, and the catalyst layer was shown to be reusable, thereby decreasing the need for catalyst renewal during a proposed continuous or semi-continuous process where the stainless steel sheet serves as a moving belt to enable forest growth at one belt end and carbon nanotube yarn or sheet fabrication at an opposite belt end.

We report an efficient method for anchoring Pt clusters (e.g., 6 nm in size) on the surfaces of N-doped multi-walled carbon nanotubes (MWNTs-CN x ) using a relatively simple method consisting of a hydrothermal treatment of Na 2 [PtCl 6 ] · 6H 2 O and N-doped nanotubes dispersed in acetic acid. The catalytic properties of this material were evaluated finding that the conversion of cinnamaldehyde using Pt-coated MWNTs-CN x could increase up to 6 times with respect to that obtained for uncoated MWNTs-CN x and pure carbon CNTs. Therefore, we envisage this material could be either used as an efficient catalyst or as a sensor.