Ag₂S doped chalcogenide glassy systems have been characterised on the basis of AC conductivity and electric modulus formalism. Various nanophases such as Ag₂Se, Te_0.5 Se_3.5 etc. and dislocation (defects) have been identified and their roles in the conduction process have been established. XRD analysis provides that incorporation of more Ag₂S content in the present system should play important role to enhance the dislocation and to decrease the crystallite sizes. The Fourier transform infrared spectra (FT-IR) confirm the characteristic vibration of Ag–S at 500–650 cm⁻¹, stretching vibrations of the O–H bond near 3400 cm⁻¹ and bending vibrations of the adsorbed H₂O molecules on the surface of Ag₂S near 1600 cm⁻¹. Composition dependent optical phonon frequency (ν₀) and Debye temperature (θ _D) have been estimated from FT-IR and it is noteworthy that θ _D increases with Ag₂S content in the compositions up to x = 0.1, but decreases for x = 0.2. This result suggests higher kinetic energy of the constituent atoms/molecules, which may refer to higher electrical conductivity due to polaron hopping. Correlated barrier hopping (CBH) model in its modified version has been found most suitable model to explore the conduction mechanism. Short time relaxation process may be considered to be trivially associated with conduction of polaron. universal scaling approach proposed by Ghosh and Pan has been adopted to interpret electrical relaxation process from time-temperature superposition principle. AC conductivity spectra at various temperatures exhibit a perfect overlap into a single master curve. This feature must be an indication of the temperature independent relaxation process. On the other hand, conductivity spectra of all the compositions at a particular temperature do not exhibit perfect overlapping into a single master curve. This result indicates that the relaxation dynamics of charge carriers (polarons) is strongly dependent on compositions.

The primary focus of this work is on the numerical modeling of lead-free methyl ammonium antimony iodide (MA3Sb2I9) based on perovskite solar cells (PSCs) by deploying solar cell capacitance simulator (SCAPS). In our work, antimony-based low bandgap perovskite in p-i-n heterojunction configuration fluorine doped tin oxide (FTO)/Cu:NiO/MA3Sb2I9/ZnO/Al has been considered as the key component of the solar cell, which has a power conversion efficiency (PCE) of 22.03%. In the meantime, we have also considered several other materials as an electron transport layers (ETL) and a hole transport layer (HTL) to improve their performance. However, the incorporation of 2, $2^{\prime} $ ,7, $7^{\prime} $ -Tetrakis[ ${N}$ , ${N}$ -di(4-methoxyphenyl)amino]-9, $9^{\prime} $ -spirobifluorene (Spiro-OMeTAD) and ZnO as a carrier transporting material (CTM) with MA3Sb2I9 material resulted in a PCE of 23.01% under the photoillumination of AM1.5.

In this work, the development and electrical characterization of several chalcogenide glassy-nanocomposites have been reported.

A strong candidate for photovoltaic technology, perovskite-based solar cells with a planar structure offers a very high power conversion efficiency (PCE). In the meantime, the strive for lead-free perovskites solar cells (PSCs) is also enhanced owing to the extremely hazardous and carcinogenic nature of lead. Due to their advantageous physical, chemical, optoelectronic, and stability properties, hybrid antimony-based materials have been proposed as an alternative and potential replacement for hazardous lead-based perovskite with the aim of obtaining harmful lead-free PSCs. Recombination in the perovskite layers reduces the performance of hetero-junction-based devices. The homojunction is suited for further PCE improvement because of the electric field that is already there; this will increase the transmission of photo-generated charge carriers while reducing recombination losses. The present work is a comprehensive analysis of planar homojunction perovskite photovoltaic devices based on MA3Sb2I9. Our study reports that the reported PSCs have PCE of 19.84% for the AM1.5 solar spectrum. Additionally, pn-homojunction has been added, which increases the efficiency of the reported device to 21.16%. Thus, this study indicates that the lead-free PSCs are extremely promising and they can be designed for a wide range of photovoltaic applications.