Highly Sensitive and Selective Acetylene CuO/ZnO Heterostructure Sensors through Electrospinning at Lean O 2 Concentration for Transformer Diagnosis

Acetylene (C H ) is a gas that can cause explosions in transformers even at low concentrations. Gas chromatography (GC) or photoacoustic spectroscopy (PAS) have been used to detect C H during dissolved gas analysis (DGA), but they are not suitable for monitoring numerous transformers at substations. Even though metal oxide semiconductor (MOS) based C H sensors have drawn much attention as a potential solution, existing MOS-based C H sensors have low sensitivity toward C H in the transformer environment (10 h). In addition, the CZ2 sensor also shows a high selectivity (>5 times) to coexisting transformer oil gases which are H , CH , C H , C H , CO, and CO . Overall, this study is the first to demonstrate a high performing DGA sensor under 2% O concentration that can provide a practical solution to monitoring the low concentration of C H in transformers effectively.