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The emergence of fluorescence quantum dots (QDs) has led to the development of variety of applications in science and technology. Owing to the diverse optical and electrical properties of CdS QDs we have synthesized the same using wet chemical method. The QDs have been prepared at sub-room temperature using a new solvent comprising a mixture of water and methanol. The QDs when seen under UV light radiate violet color. The band-gap of the QDs deduced from the absorption spectra was 3.08 eV while PL spectra of the QDs suggested possibility of multiple exciton generation with a close to narrow size distribution. XRD analysis confirmed cubic structure of the particles. The obtained results suggest that these QDs can play ideal role in quantum dot sensitized solar cells (QDSSC) or in light emitting diodes (LEDs).

As a promising solar absorber material, antimony selenide (Sb2Se3) has gained popularity. However, a lack of knowledge regarding material and device physics has slowed the rapid growth of Sb2Se3-based devices. This study compares the experimental and computational analysis of the photovoltaic performance of Sb2Se3-/CdS-based solar cells. We construct a specific device that may be produced in any lab using the thermal evaporation technique. Experimentally, efficiency is improved from 0.96% to 1.36% by varying the absorber’s thickness. Experimental information on Sb2Se3, such as the band gap and thickness, is used in the simulation to check the performance of the device after the optimization of various other parameters, including the series and shunt resistance, and a theoretical maximum efficiency of 4.42% is achieved. Further, the device’s efficiency is improved to 11.27% by optimizing the various parameters of the active layer. It thus is demonstrated that the band gap and thickness of active layers strongly affect the overall performance of a photovoltaic device.

A maximum e ciency of 17% for ultra-thin n-type AZO layer and 17.5% for ultra-thin n-type TiO 2 layer based silicon heterojunction solar cell is reported by optimizing its properties which is much higher than practically obtained e ciency signifying a lot of improvements can be performed to improve e ciency of TiO 2 /Si and AZO/Si heterojunction solar cell. AZO layer and TiO 2 layer is used as n-type emitter layer and crystalline silicon wafer is used as p-type (p-cSi) layer for modelling AZO/Si and TiO 2 /Si heterojunctions solar cell respectively using AFORS HET automat simulation software. Various parameters like thickness of AZO, TiO 2 layer, p-cSi layer, doping concentration of donors (Nd) and effective conduction band density (Nc) are optimized. Finally, texturing at different angle is studied and maximum e ciency is reported at 70 µm thick p-type crystalline Silicon (p-cSi) wafer, that can be very helpful for manufacturing low cost HJ solar cells at industrial scale because of thin wafer and removal of additional processing setup required for deposition of amorphous silicon i-layer. Utilization of TiO 2 and Aluminium doped Zinc Oxide as n-type layer and p-cSi as p-type layer can help in producing low cost and e cient heterojunction (HJ) than compared to HJ with intrinsic thin layer HIT solar cells.