**1.1 Conventional solar panels**

Solar energy is the cleanest source of renewable energy on earth. Solar cell works on the principle of photoelectric effect that converts solar energy into electrical energy. Solar cells are mainly categorized into four generations. The conventional mono and polycrystalline wafer-based solar cells are first-generation [1, 2]. Thin films solar cells such as CIGS, CdTe, and CZTS are second-generation of solar cells. Multijunction solar cells are third-generation solar cells. Quantum dot and hybrid solar cells are fourth generation of solar cells. Theoretically, each generation of solar cells has energy conversion efficiency. Experimentally, multijunction solar cells have achieved the highest energy conversion efficiency, about 47.5%. Silicon solar cells are mostly commercialized technology due to abundant and cheap materials. However, its fabrication involves expensive and toxic processes. Currently, solar panels are used as off-grid and rooftop on-grid applications. Therefore, novel solar panel technology is required for multiple applications such as windows, displays, surface, etc. [3–5].
