High voltage gradient and low leakage current SnO2 varistor ceramics doped with Y2O3 and Nb2O5

SnO2 varistors are a type of ceramic material with strong heat dissipation and nonlinearity. To improve the overall nonlinear electrical properties of SnO2 varistor ceramics, we studied the electrical properties and microstructure of SnO2 varistors doped with different contents of Nb2O5 at a given concentration of Y2O3. We studied the electrical characteristics of the obtained experimental samples by scanning electron microscope imaging, voltage-current and capacitance-voltage measurements, and X-ray diffraction. When the SnO2 varistor ceramic samples were fabricated with 0.006 mol% niobium and 0.05 mol% yttrium, excellent electrical performance was achieved with a voltage gradient of 832.4 V/mm, leakage current of 4.31 mu A/cm(2), and nonlinearity coefficient of 45. This study will help guide efforts to strengthen the electrical performance of SnO2 varistors.