Insight into electro chemical and dielectric properties of flower shaped samarium embedded Y₂O₃@SeO₂ nanocomposites for H₂O₂ sensor applications

The rapid advancement in the sensor technology is critically influencing structure and morphology of the materials used. The researchers are taking keen interest in developing novel materials as sensors and actuators. In this work, Samarium doped Y2O3@SeO2 (Sm-x:Y2O3 @SeO2, x = 1%, 8% and 12%) nanocomposites (NC) have been synthesized using microwave assisted method. The effect of Sm3+ substitution over Y2O3 @SeO2 NC have been explored for morphological, structural, optical, sensor and dielectric properties. Crystal structure have been examined by X-ray diffraction (XRD) pattern and showed mixed phase of hexagonal/cubic structure. Morphology of the grains significantly affected by Sm3+ doping, resulted into flower/flake like microstructure. Redshift in optical absorption peak attributed to the enhancement of defect density with Sm3+ doping. The measurement of in depth morphology of the NC investigated using transmission electron microscopy (TEM), showed flower/flake shaped grains with size similar to 16 nm. Frequency dependence real (epsilon') and imaginary parts (epsilon") of dielectric constants at various temperatures ranging from 50 C-degrees to 250 C-degrees showed increase in (epsilon') as Sm3+ doping increases on Y2O3 @SeO2 NC. The Sm-12%:Y2O3 @SeO2 showed greater sensitivity towards hydrogen peroxide (H2O2) when exposed to volatile gases as compared with Y2O3 @SeO2 NC. An exceptional limit of detection (LOD) of similar to 0.68 mu M has been realized. The non-enzymatic sensor was capable of detecting H2O2 with a wide linear range of 2-350 mu M, linear regression of R-2 = 0.991 with a high sensitivity of 26 mu A mM(-1). The present investigation can be used to develop sensors, optoelectronic devices and actuators.