Synthesis and characterization of aluminum carbide-derived carbon with residual aluminum-based nanoparticles

An in-depth study on the etching process for producing carbide-derived carbons from Al4C3 has been performed. These materials were investigated at a range of etching temperatures from 300 to 900 °C and a range of times from 15 min to 6 h. By altering the etching time and temperature, the surface area, residual aluminum content, and pore size distribution can be tuned. A maximum surface area of 1126 m2 g−1 was observed for materials etched at 500 °C for 1 h. The pore size has shown to be tunable from ≤0.7 to 8 nm. Interestingly, aluminum-based nanoparticles were observed via TEM and SEM for partially etched samples, with evidence of tunable metal species on the surface of the Al4C3-CDC samples at different etching temperatures between 300 and 700 °C. Characterization of the aluminum species present over this temperature range took place using solid-state 27Al NMR. The formation of crystalline α-Al2O3 was observed at etching temperatures of 700 °C. The results of this work provide detailed synthesis strategies for controlling not only the porosity and surface area of a carbide-derived carbon, but also the extent and type of residual metal nanoparticles embedded in the final structure. [Display omitted]