Highly black material made from activated carbon

Abstract Low-reflectance black materials play an important role in optical and thermal devices. In this study, boron-doped carbon nanowalls (CNWs) with extremely low reflectance were successfully synthesized using an inexpensive and simple experimental arrangement. Analysis of the nanostructures and surface morphology of the CNWs revealed that boron-doped CNWs had a higher wall density and lower graphitization than undoped CNWs. We discuss the mechanism of light absorption in terms of stray light effects originating from the nanostructures and the improved electrical conductivity owing to carrier doping. Boron-doped CNWs are considered beneficial for the implementation of this ultra-black material.