Executive Summary : | The two-dimensional (2D) materials, especially, the materials that belong to the category of transition metal di-chalcogenides (TMDCs) have revolutionized the perspectives of material applications. Their electronic and mechanical properties are reported to be comparable to that of 2D graphene, additionally, they have optical absorption in the visible region. This has opened up their wide applications into opto-electronics. TMDCs are being explored in photovoltaics for enhancing the photon-to-electron conversion efficiency and charge transport efficiency. However, the implications of TMDCs into all-inorganic solar cells are found meager. Photovoltaics based on perovskite materials have exhibited great promises in terms of its performance. Amongst, all-inorganic perovskite solar cells have reported better performance stability compared to other perovskite solar cells. The excellent physical and chemical properties of TMDCs can be explored to enhance the performance of these solar cells. This project intends the utilization of the properties of TMDCs (MoS₂, WS₂ and MoSe₂) to enhance the photo-to-electron conversion efficiency of all-inorganic perovskite (CsPbBr₃) based solar cells. Three different approaches for effective photon management in the inorganic perovskite solar cell through the inclusion of TMDCs are being proposed in this project. Project aims in enhancing the performance of perovskite based solar cells through the incorporation of TMDCs at three different interfaces. Firstly, in the photo absorber perovskite material, secondly, at the interface of absorber material and electron transport layer, and thirdly, as an electron transport layer. In the first section, the photoactivity as well as the efficient charge transport properties of the semiconducting TMDCs in the perovskite material will be studied. Further, its effect in enhancing the solar cell performance and in the stability of the inorganic perovskite will be evaluated. The heterojunction of perovskite and TMDC have been reported to form junctions for efficient charge separation. This can lead to a significant reduction in the charge recombination. In the second section, the incorporation of plasmonic nanoparticles in TMDCs will be studied as it is introduced in intermediate layer between the perovskite and hole transport layer. The presence of metallic nanoparticles is hypothesized to scatter back the photons that escape the absorber layer. In addition, the presence of plasmonic nanoparticle could enhance the photoabsorption of TMDCs, thus, generating excess charge carriers. In the third section, 2D heterostructure of TMDC and its oxidized counter-part is to be studied as electron transport layer. This heterostructure that is photoactive in the visible region and having excellent charge transport properties could contribute to the photocurrent. All these works could lead to enhancement in the power conversion efficiency of the CsPbBr₃ perovskite solar cells. |