Colloidal synthesis of ternary semiconductor nanostructured materials with high NIR absorption

Abstract

Nanoscience is an expansive and rapidly evolving field with diverse applications across multiple disciplines. Over the past 50 years, advancements in nanomaterials have significantly impacted areas such as physics, chemistry, biology, and engineering, leading to innovations in electronics, medicine, and environmental science. This project focuses on the development of ternary semiconductor Wittichenite (Cu3 BiS3 ) nanoparticles. These nanoparticles are a promising alternative to the currently dominant light-absorbing materials in thin-film solar cells, such as Copper Indium Gallium Selenide (CIGS), Copper Indium Selenide (CIS), and Cadmium Telluride (CdTe). The primary advantages of using Cu3 BiS3 lie in the abundance and lower toxicity of its constituent elements, copper and bismuth. Additionally, binary sulfides like Bi2S3 and Cu2S already demonstrate suitable bandgaps (ranging from 1.2 to 1.5 eV) and high absorption coefficients for the solar spectrum, encompassing visible, ultraviolet (UV), and infrared (IR) light . The ternary compound Cu3BiS3 is expected to exhibit enhanced properties, such as improved stability, homogeneity, an optimal bandgap, and efficient near-infrared (NIR) absorption, making it a viable candidate for next-generation solar cell materials. The synthesis method employed in this project follows a bottom-up approach, which is generally simpler and more straightforward than top-down methods for nanoparticle preparation. Specifically, colloidal thermal decomposition, a solution-based technique, is used due to its superior versatility and precise control over the nanoparticle size, shape, and phase. This method facilitates the production of high-quality nanoparticles that meet the desired criteria for advanced photovoltaic applications