Novel green phosphorene as a superior gas sensor for dissolved gas analysis in oil transformers: using DFT method

Regarding recent attempts for monitoring dissolved gases in oil transformers, in this paper, novel green phosphorene (GP), a new type of two-dimensional gas sensitive material was modified by transition metal decoration. We applied first-principles calculations based on Density functional theory and investigated the structures and electronic properties of H2, CH4, and C2H2 (dissolved gases) molecules adsorbed on the pristine, and metal decorated (Pt, and Pd) GP monolayer to understand its performance as a sensor. This analysis indicated that Pt-GP could be a satisfying material for C2H2 sensing at specific conditions, while it is unsuitable for detection of CH4, and H2 due to the weak interaction and short recovery time. The adsorption energy (Ead) of C2H2 on Pd-, Pt-GP systems is −1.18, and −1.84 eV, respectively, and 4, and 2 times more electrons were transferred from the C2H2 molecule to the systems, respectively in comparison with the pristine GP. Moreover, Pd-GP has a recovery time of 9.68 s under visible light at 350 K indicating that it is suitable for reusability, and it has a good sensitivity of 65.9% toward C2H2 molecule. Our results showed that the metal-decorated GP sensors are excellent candidates for analyzing dissolved gases in oil-based transformers.