Scientists at Lawrence Livermore National Laboratory (LLNL) have created carbon nanotubes with straight walls and metal sheets that could be useful for energy storage and electronics industries. Vertically aligned carbon nanotubes (VACNTs) (Enter the carbon nanotubes) have unique structural, electrical and transport properties in addition to integrated structures, which are important for applications such as membrane separation, heat control, fiber conversion, electronic connectivity and energy storage.
To date, the widespread integration of VACNTs into next-generation technologies is hampered by a lack of cost-effective mass production capabilities. Advanced VACNTs are typically fabricated on materials such as silicon (Si) or quartz wafers that are tough, expensive, and thermally insulating.
After researching metal foil options in the scientific literature, the LLNL team turned to Inconel metal substrates that allow them to incorporate VACNTs (Enter the carbon nanotubes) into flexible devices, eliminate the transfer from Si to d other materials and reduce material electrical or thermal transport barriers at the interface between CNT and substrate. , which is important for electrical appliances and energy storage. Inconel is a family of superalloys of nickel-chromium that is an excellent oxidation-corrosion inhibitor for work in extreme environments under pressure and temperature.
“The transfer of high-quality CNT materials from traditional Si substrates to metal foils opens another way to store, large-scale, semi-continuous and roll-up of multifunctional CNT composites, nanoporous membranes and electrochemical devices, ” said. LLNL scientist Francesco. Fornasiero, co-author of an article published in the journal Applied Materials & Interfaces.
The combination of high single-walled CNTs (SWCNTs) and metal foils will be particularly useful for energy storage devices, such as lithium-ion batteries (LIBs). Although photoconductors are common LIB anodes, their capabilities are in line with rapidly changing energy storage needs.
“The high surface area and exceptional electronic conductivity of CNTs make them prime space for high capacity, high output electrochemical applications,” said LLNL scientist Kathleen Moyer-Vanderburgh, lead author of the paper. “Specifically, VA-SWCNTs grown on metal foils can provide a platform without adhesives and a strong connection between the SWCNT and the current collector, good conductivity, and a channel prepared for fast Li-ion diffusion .”
The LLNL team grew a forest of SWCNTs aligned on Inconel metal for use as LIB anodes. The team observed nearly identical properties of CNT forests in many structural conditions and for many mechanical properties. The fabricated VA-SWCNT LIB anode has shown stable cycling for hundreds of cycles and high capacity even at high cycle rates.
“Our results show that these Inconel-metal SWCNTs are promising materials for advanced electrochemical devices,” said LLNL scientist Jianchao Ye.
