From CIGS to Kesterite: Advancements in Solar Cell

The evolution of solar cell technology has seen significant progress, particularly in thin-film photovoltaics. Copper indium gallium selenide (CIGS) solar cells have gained prominence due to their high efficiency and tunable bandgap, making them well-suited for specific applications. However, the scarcity and cost of indium have prompted the search for more sustainable alternatives. Kesterite (Cu₂ZnSn(S,Se)₄), composed of earth-abundant and non-toxic elements, has emerged as a promising low-cost candidate. While neither CIGS nor kesterite competes directly with silicon-based solar cells both are ideal for niche applications where flexibility, lightweight structures, and customization are crucial. These properties make them highly suitable for building-integrated photovoltaics (BIPV) and product-integrated photovoltaics (PIPV), driving innovation in urban energy solutions. In this talk, we will explore the properties of these materials and their connection to growth processes, as well as how recent advancements in material engineering and defect control are improving kesterite's efficiency, narrowing the gap with CIGS.