Observation of room temperature metal free ferromagnetism in sulfur doped graphitic carbon nitride

Generation of superior magnetic property in two-dimensional nanosheets is an important issue in condensed matter physics due to its potential exploitation in the field of Spintronic application. Metal-free ferromagnetism in 2D materials could generate a long spin lifetime due to its s/p electron configuration, which is the key factor for spin transfer. In the present work, we have synthesised 2D graphitic carbon nitride doped with sulfur (S) atom to investigate the magnetic property due to the interaction of the S atom with the lattice of graphitic carbon nitride. Due to S doping, we get a long-range ferromagnetic ordering in our sample, persisting upto room temperature, and the precise control of S concentration can tune the magnetic property of the system. Interestingly, the magnetotransport (MR) study shows a transition from positive MR at low temperature to negative MR at room temperature. The wave function shrinkage model explains the low-temperature positive MR, where the negative MR follows the weak localization effect. Thus, the overall magnetic and electrical response of S doped graphitic carbon nitride makes it a potential candidate for future spintronic application.