Investigation of structure, dielectric, thermistor, and optical properties study of an eco-friendly double perovskite for photovoltaic and optoelectronic applications: CaLiFeWO6

Double-perovskite oxides have received interest recently because of their appealing photovoltaic and optoelectronic properties for promising applications. In this paper, we demonstrate the synthesis (solid-state reaction) as well as characterization study of an eco-friendly novel double perovskite CaLiFeWO₆. Preliminary investigation of X-ray diffraction (XRD) data reveals a monoclinic structure. Micro-lattice strain and average size of crystallite are found to be 0.000564 and 86 nm. The distribution of grains and elemental composition of the sintered sample was recorded using scanning electron microscope (SEM) cum energy dispersive X-ray spectroscopy (EDX). Raman scattering spectroscopy is tailored to study the vibrational Raman modes involved in the sample. The optical analysis was investigated by employing UV visible spectroscopy and used to obtain bandgap energy within the range for optoelectronic device applications. To understand the electrical behavior of the synthesized double perovskite, the authors conducted both low and high-frequency dielectric measurements and utilized impedance spectroscopy. The conductivity behavior in the studied material follows Jonscher's power law. Resistance versus temperature data supports the concept of negative temperature coefficient (NTC) thermistors for temperature sensors and temperature control systems. Polarization-electric field supports the possibility of ferroelectric behavior, which opens the door to a wide range of technological advancements and innovations in various fields.