Carbon-based self-powered terahertz detector with multi-walled carbon nanotubes-graphene heterostructure

A vertically aligned multi-walled carbon nanotubes (MWCNTs) array was synthesized via the chemical vapor deposition (CVD) method and subsequently transformed into horizontally ordered films using a mechanical roll-pressing technique, and these films were then stacked with graphene to form a van der Waals (vdW) heterostructure. In the metal-MWCNTs-graphene-metal structure, low-energy photon detection in the submillimeter-wave and terahertz (THz) spectral range is achieved at room temperature. The results demonstrate that without external bias conditions, the device exhibits a remarkable responsivity of up to 24.6 mA/W at 0.11 THz, with a response time of only 12.6 μs and a noise equivalent power as low as 64.1 pW Hz−0.5. These research findings represent an important step in exploring the efficient application of carbon-based materials in low-energy THz photon detection.