Synthesis and Characterisation of Small Thiophene Analogues for Organic Photovoltaic Cell Applications

With an increase in the energy crises, it is vital to find substitute sources of energy. Various sources of alternative renewable sources are being developed. Due to its semiconductor properties, silicon is the metal of choice for manufacturing solar cells. Though silicon-based solar cells are commercialised globally, the cost involved in mining purified silicon is high, causing hindrances in the usage of silicon-based solar cells. Hence, second-generation solar cells, consisting of organic polymers are preferred. However, the stability and efficiency of polymer-based solar cells is still a challenge. Many inorganic semiconductor materials having greater efficiency are being manufactured. However, manufacturing processes, on the other hand, are both material and method-intensive. As a result, Organic-Based Photovoltaic (OPV) cells are gaining popularity because of their potential for low-cost solar energy collection and the abundance and ease of handling organic materials. The present research focuses on developing low-cost, flexible organic semiconductor materials with unique properties including flexibility, lightness, nontoxicity and transparency as well as large-area OPV panels that can be produced with inexpensive methods of solution processing. These benefits suggest that they have a wide range of applications and complement classic silicon-based OPV cells. Their excellent light harvesting, natural charge transport behaviour and structural adaptability, thiophene-based conjugated systems have sparked a lot of attention in the development of high-performance organic solar cells. As a result, fused thiophenes and their analogues have been synthesised for use as organic semiconductor materials in OPVs, and they have been characterised using1 Proton Nuclear Magnetic Resonance (HNMR), Ultra Violet (UV)-Visible Spectrophotometer and the Tauc equation and graphs. The band gap of each analogue has been determined. Further, the synthesised compounds are characterised for photovoltaic applications using I-V characterisation techniques.