Ni-Doped PtSe ₂ for Dissolved Gas Detection in Transformer Oil: A First-Principles Study

Large power transformers are widely used in power systems, and ensuring their reliable operation is crucial for power grid security. Dissolved gas analysis in oil is a mature and widely accepted method for transformer fault diagnosis. In this paper, a Ni-PtSe 2 -based method for detecting dissolved gases in oil is proposed, and the response characteristics of Ni-doped PtSe 2 to dissolved gases in oil is systematically investigated. The adsorption energies of Ni-PtSe 2 for typical dissolved gases in oil—CO, H 2 , CH 4 , C 2 H 2 , and C 2 H 4 —are -2.0525 eV, -0.6985 eV, -0.4298 eV, -1.677 eV, and -2.438 eV, respectively. CO, C 2 H 2 , and C 2 H 4 are chemically adsorption, while H 2 and CH 4 are physical adsorption. Furthermore, H 2 exhibits a strong physical adsorption interaction with the substrate. At room temperature, Ni-PtSe 2 exhibits high sensing sensitivities for CO, H 2 , C 2 H 2 , and C 2 H 4 , with sensitivities of 50.55, 42.36, 66, and 15, respectively. The adsorption recovery time for H 2 is only 0.636 s, indicating easy desorption and highlighting its excellent adsorption and sensing performance. With its ultrafast H 2 desorption kinetics and reasonable adsorption sensitivity, Ni-PtSe 2 shows promise as a reusable H 2 sensor and is a practical candidate material for H 2 detection in the field of dissolved gas analysis in oil.