Memristive effects within stacking faults consisting of locally coexisting rhombohedral and Bernal lattices in exfoliated graphite and multilayered carbon nano-onion†

Abstract

The identification of ferrimagnetic spin-order, ferroelectricity and superconductivity in rhombohedral graphene and graphite has recently attracted significant interest. Here we report an in-depth investigation on the properties of specific categories of stacking faults in exfoliated pyrolytic graphite, by employing a combination of atomic force microscopy (AFM) and Raman point and mapping spectroscopy techniques. We propose a systematic analysis of (1) locally lifted-lattices, (2) staircase-lattices and (3) disclinations. Statistical investigation of the 2D-band evidences a clear coexistence of rhombohedral and Bernal phases. AFM current vs. voltage acquisitions highlight the observation of a pinched memristive hysteresis. Comparative analyses performed on multilayered lattices of carbon nano-onions which exhibited an important broadening of the 2D band revealed an analogous trend, with observable memristive-hysteresis. A weakening in the amplitude of these signals was interestingly found in S-modified CNO samples, as a consequence of S-induced structural amorphization of the CNOs. The presented results open up new avenues towards the possible applicability of these multilayered nanoscale structures in nanoelectronics.