Quantum-sized nanomaterials for solar cell applications

Abstract

To date, the development of clean and sustainable energy sources has been a central focal point of research, supporting the worldwide rising demand for energy along with associated environmental concerns. The abundance of solar energy on the surface of the earth and its popular appeal makes it a promising candidate to comply with long-term energy demands. In this article, we provide a comprehensive review on different generations of solar cell based on the technological and economic aspects. The focus is on nanomaterial-based solar cells such as quantum dot sensitized solar cells (QDSSCs), a new PV mechanism that offers a new pathway for controlling energy flow. Over the past few years, a significant improvement has been achieved in the energy conversion efficiency (ECE) of QDSSCs (e.g., from 1% to beyond 11%). As such, they are a very promising alternative to conventional crystalline and thin film PV technologies due to their low cost, easy fabrication, and high performance. This review highlights the progress of QDSSCs along with future scope of innovative graphene structures, e.g., graphene-semiconductor nanomaterial (G-SNM), graphene-carbon nanotubes (GCNT), and graphene-metal nanomaterial (G-MNM) hybrids in PV cells. In addition to graphene, we discuss other 2D materials that have remarkable optoelectronic properties for PV devices. The ECE of green QDSSCs (similar to 11.61% certified) is now approaching that of dye-sensitized solar cells (similar to 13%) through the technical advancement of many counterparts (e.g., photo-electrodes, sensitizers, electrolytes, and counter electrodes). Therefore, QDSSCs exhibit sufficient potential for future research focusing on the development of highly efficient solar cells.