Nanoporous Cu–C composites based on carbon-nanotube aerogels

Current synthesis methods of nanoporous Cu-C composites offer limited control of the material composition, structure, and properties, particularly for large Cu loadings of [gap]20 wt%. Here, we describe two related approaches to realize novel nanoporous Cu-C composites based on the templating of recently developed carbon-nanotube aerogels (CNT-CAs). Our first approach involves the trapping of Cu nanoparticles while CNT-CAs undergo gelation. This method yields nanofoams with relatively high densities of [gap]65 mg cm super(-3) for Cu loadings of [gap]10 wt%. Our second approach overcomes this limitation by filling the pores of undoped CNT-CA monoliths with an aqueous solution of CuSO sub(4) followed by (i) freeze-drying to remove water and (ii) thermal decomposition of CuSO sub(4). With this approach, we demonstrate Cu-C composites with a C matrix density of similar to 25 mg cm super(-3) and Cu loadings of up to 70 wt%. These versatile methods could be extended to fabricate other nanoporous metal-carbon composite materials geared for specific applications.